# Organic Chemistry/Glossary

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\> Glossary

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## A

-   Acetal - a molecule with two single bonded oxygens attached to the
    same carbon atom

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-   Acetyl - a functional group with chemical formula -COCH3

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-   Achiral - a group containing atleast two identical substituents

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-   Acid anhydride - hydrocarbon containing two carbonyl groups.Acyl
    group attached with carboxylate group. eg RCOOCOR\'

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-   Acid halide - acyl group with any halogen attached with carbon of
    carbonyl group. eg RCO-X(X=F,Cl,Br,I).

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-   Acidity constant K~a~ -

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-   Activating group - any group which activates a molecule by
    increasing positive or negative charge on a carbon atom. Mainly
    towards neucleophilic or electrophilic substitution reactions.

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-   Activation energy - the energy required for reactants to cross
    energy barrier to undergo any chemical change; denoted by E~a~.

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-   Acyl group - a group having an alkyl or aryl group with a carbonyl
    group RCO-

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-   Adam\'s catalyst - a catalyst for hydrogenation and hydrogenolysis
    in organic synthesis. Also known as platinum dioxide

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-   Addition
    reaction -
    a reaction where a product is created from the coming together of 2
    reactants.

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-   Alcohol - a saturated hydrocarbon chain with an -OH functional
    group.

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-   Aldehyde - a hydrocarbon containing at least one carbonyl group
    having one hydrogen attached to it.(\>C=O)

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-   Aldol reaction - a reaction of two aldehydes yielding a product with
    both an aldehyde(\>C=O) and an alcohol() group.

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-   Aliphatic - A non-cyclic, non-aromatic, hydrocarbon chain (e.g.
    alkanes, alkenes, and alkynes)

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-   Alkane - A hydrocarbon with all the carbon-carbon bonds are single
    bonds.

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-   Alkene - A hydrocarbon with at least one carbon-carbon bond is a
    double-bond.

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-   Alkoxide ion - The conjugate base of an alcohol without the terminal
    H atom. For any alcohol R-OH, the corresponding alkoxide form is
    R-O^-^.

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-   Alkyl - A hydrocarbon having formula C~n~H~2n+1~

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-   Alkylation - Addition of alkyl group in a compound.

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-   Alkyne - An unsaturated hydrocarbon containog triple bond.and having
    general formula C~n~H~2n-2~

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-   Allyl - An alkene hydrocarbon group with the formula H2C=CH-CH2-

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-   α Position - Carbon attached to a functional group is called
    α-carbon and the position is known as α position.

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-   α-carbon - Carbon attached to a functional group is called α-carbon

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-   Amide - A hydrocarbon containing amine group attached to acyl group.
    eg.- RCONH~2~

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-   Amine - A simple hydrocarbon containing atleast one -NH~2~ group.

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-   Amino Acid - A fundamental unit of polypeptides or proteins.having
    general formula-COOHRCHNH~2~.eg.- glysine, alanine etc.

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-   Anti conformation -

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-   Anti periplaner -

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-   Anti stereochemistry -

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-   Anti bonding molecular orbital - Molecular orbitals having higher
    energy than bonding molecular orbitals after combination of atomic
    orbitals.denoted by an astric over Sigma or pi notations.

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-   Arene - Another name for an aromatic hydrocarbon.

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-   Aromaticity - A chemical property in which a conjugated ring of
    unsaturated bonds, lone pairs, or empty orbitals exhibit a
    stabilization stronger than would be expected by the stabilization
    of conjugation alone.

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-   Atomic mass - Total no of nucleon i.e. number of proton and number
    of neutrons. Atomic mass is denoted by A.

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-   Atomic number - Total no. of protons is called the atomic number.

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-   Axial bond - The bond parallel or antiparallel to axial coordinate
    passing center of gravity.

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-   Azide synthesis - Dutt-Wormall reaction in which a diazonium salt
    reacts with a sulfonamide first to a diazoaminosulfinate and then on
    hydrolysis the azide and a sulfinic acid.

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-   Azo compound - A compound containing -N=N group.

## B

-   Benzoyl Group - The acyl of benzoic acid, with structure C6H5CO-

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-   Benzyl Group - The radical or ion formed from the removal of one of
    the methyl hydrogens of toluene (methylbenzene).

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-   Benzylic -

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-   β position -

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-   β-carbon -

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-   Bicylcoalkane - A compound containing two cyclic rings.

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-   Bimolecular reaction - A second order reaction where the
    concentration of two compounds determine the reaction rate.

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-   Boat cyclohexane - A less-stable conformation of cyclohexane that
    somewhat resembles a boat.

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-   Bond - The attractive forces that create a link between atoms. Bonds
    may be covalent or ionic.

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-   Bond angle - The angle formed between three atoms across at least
    two bonds.

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-   Bond length - The average distance between the centers of two atoms
    bonded together in any given molecule.

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-   Bond strength - The degree to which each atom linked to a central
    atom contributes to the valency of this central atom.

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-   Bonding molecular orbital -

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-   Bromonium ion -

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-   Brønsted-Lowry
    Acid
    -

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-   Brønsted-Lowry
    Base
    -

## C

-   Cahn-Ingold-Prelog priorities - A rule for assigning priorities to
    substituents off of carbon in a double-bond or in a chiral center.

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-   Carbocation -

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-   Carbonyl group - A functional group composed of a carbon atom
    double-bonded to an oxygen atom: C=O.

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-   Carboxylation - A chemical reaction in which a carboxylic acid group
    is introduced in a substrate.

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-   Carboxylic acid - An organic acid characterized by the presence of a
    carboxyl group.

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-   Chain reaction - A sequence of reactions where a reactive product or
    by-product causes additional reactions to take place

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-   Chair cyclohexane -

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-   Chiral - A term used to describe an object that is non-superposable
    on its mirror image

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-   Chiral center - A carbon atom bonded to four different groups

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-   Chromatography - The process of separating compounds such as a dye
    into its constituents

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-   Cis-trans isomers -

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-   Claisen condensation reaction -

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-   Claisen rearrangement reaction -

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-   Concerted -

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-   Configuration - the permanent geometry of a molecule that results
    from the spatial arrangement of its bonds.

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-   Conformation -

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-   Conformer -

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-   Conjugate acid -

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-   Conjugate base -

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-   Conjugation - A system of atoms covalently bonded with alternating
    single and multiple (e.g. double) bonds (e.g., C=C-C=C-C).

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-   Covalent bond - A form of chemical bonding that is characterized by
    the sharing of pairs of electrons between atoms.

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-   Cracking - The process whereby complex organic molecules such as
    heavy hydrocarbons are broken down into simpler molecules (e.g.
    light hydrocarbons) by the breaking of carbon-carbon bonds.

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-   Cycloaddition reaction -

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-   Cycloalkane - An alkane that has one or more rings of carbon atoms
    in the chemical structure of its molecule.

## D

-   Debye -

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-   Decarboxylation -

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-   Delocalization - The ability of electrons to spread out among pi
    bonds to provide stabilization to electronically unstable areas of a
    molecule.

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-   Dextrorotatory -

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-   Diastereomers - Two or more isomers of a molecule which are *not*
    enantiomers of one another.

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-   1,3 Diaxial interaction - The steric intereaction between two methyl
    or larger groups attached at the 1 and 3 cis positions of
    cyclohexanes. The cyclohexane is in a higher energy state in the
    ring flip conformation that results in both 1 and 3 positions being
    axial due to steric strain between the 2 groups. This strain does
    not exist when hydrogens are bonded at these positions.

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-   Diels-Alder reaction -

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-   Dienophile -

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-   Dipolar -

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-   Dipole moment -

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-   Disulfide -

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-   Downfield - A term used to describe the left direction on NMR
    charts. A peak to the left of another peak is described as being
    downfield from the peak.

## E

-   E geometry -

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-   E1 reaction -

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-   E2 reaction -

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-   Eclipsed conformation -

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-   Eclipsing strain -

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-   Electron - An elementary subatomic particle that carries a negative
    electrical charge and occupies an electron shell outside the atomic
    nucleus.

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-   Electron configuration - The arrangement of electrons in an atom or
    molecule

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-   Electron-dot structure -

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-   Electron shell - The orbit followed by electrons around an atomic
    nucleus. The atom has a number of shells and they are normally
    labelled K, L, M, N, O, P, and Q.

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-   Electronegativity - The ability of an atom to attract electrons
    towards itself in a covalent bond.

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-   Electrophile - Literally, electron lover. A positively or neutrally
    charged reagent that forms bonds by accepting electrons from a
    nucleophile. Elecrophiles are Lewis Acids.

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-   Electrophilic addition reaction -

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-   Electrophilic aromatic substitution -

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-   Elimination
    reaction -
    A reaction where atoms and/or functional groups are removed from a
    reactant.

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-   Endergonic - In an endergonic process, work is done on the system,
    and ΔG^0^ \> 0, so the process is nonspontaneous. An exergonic
    process is the opposite: ΔG^0^ \< 0, so the process is spontaneous.

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-   Endothermic - An endothermic reaction is a chemical reaction that
    absorbs heat, and is the opposite of an exothermic reaction.

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-   Enol - An alkene with a hydroxyl group affixed to one of the carbon
    atoms composing the double bond.

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-   Enolate ion -

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-   Entgegen - German word meaning \"opposite\". Represented by E in the
    E/Z naming system of alkenes.

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-   Enthalpy -

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-   Entropy -

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-   Equatorial bond -

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-   Ester - An inorganic or organic acid in which at least one -OH
    (hydroxyl) group is replaced by an -O-alkyl (alkoxy) group.

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-   Ether - An organic compound which contains an ether group --- an
    oxygen atom connected to two (substituted) alkyl or aryl groups ---
    of general formula R--O--R\'.

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-   Exergonic -

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-   Exothermic - An exothermic reaction is a chemical reaction that
    releases heat, and is the opposite of an endothermic reaction.

## F

-   Fingerprint region -

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-   First order reaction - A reaction whose rate is determined by the
    concentration of only one of its reactants leading to a reaction
    rate equation of $Rate = k[X]$

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-   Fischer projection -

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-   Formal Charge -

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-   Friedel-Crafts reaction -

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-   Functional group - This is a specific group of atoms within a
    molecule that is responsible for the characteristic chemical
    reactions of that molecule. The same functional group will undergo
    the same or similar chemical reaction(s) regardless of the size of
    the molecule it is a part of.

## G

-   Geminal -

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-   Gibbs free energy -

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-   Gilman reagent -

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-   Glycol - A chemical compound containing two hydroxyl groups (-OH
    groups). Also known as a Diol.

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-   Glycolysis - The metabolic pathway that converts glucose,
    C~6~H~12~O~6~, into pyruvate, C~3~H~5~O~3~. This process usually
    occurs outside the mitochondria of a cell to help produce energy.

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-   Grignard reagent -

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-   Ground state - In electrons, the state where they have the least
    energy. Electrons that gain energy get \"excited\" and leave the
    ground state, now able to do more work. Moving electrons out of
    their ground state is a key part of photosynthesis, where plants
    create sugar from the sun, carbon dioxide, and water.

## H

-   Halohydrin formation -

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-   Hammond postulate -

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-   Hemiacetal -

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-   Hemiaminal -

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-   Heterocycle - A cyclic molecule with more than 2 types of atoms as
    part of the ring. (e.g. Furan, a 5-membered ring with four carbons
    and one oxygen, or a Pyran, a 6-membered ring with five carbons and
    one oxygen)

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-   HOMO - Acronym for Highest Occupied Molecular Orbital.

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-   Homolytic cleavage - Where bond breaks leaving each atom with one of
    the bonding electrons, producing two radicals.

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-   Hybrid orbital -

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-   Hydration - A chemical reaction in which a hydroxyl group (OH-) and
    a hydrogen cation (an acidic proton) are added to the two carbon
    atoms bonded together in the carbon-carbon double bond which makes
    up an alkene functional group.

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-   Hybride shift -

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-   Hydroboration - A reaction adding BH~3~ or B~2~H~6~ or an
    alkylborane to an alkene to produce intermediate products consisting
    of 3 alkyl groups attached to a boron atom. This molecule is then
    used in other reactions, for example, to create an alcohol by
    reacting it with H~2~O~2~ in a basic solution.

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-   Hydrocarbon - A molecule consisting of hydrogens and carbons.

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-   Hydrogen bond -

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-   Hydrogenation - Addition of a hydrogen atoms to an alkene or alkane
    to produce a saturated product.

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-   Hydrophilic - literally, \"water loving\". In chemistry, these are
    molecules that are soluble in water.

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-   Hydrophobic - literally, \"water fearing\". In chemistry, molecules
    that aren\'t soluble in water.

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-   Hydroxylation - A chemical process that introduces one or more
    hydroxyl groups (-OH) into a compound (or radical) thereby oxidizing
    it.

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-   Hyperconjugation -

## I

-   Imide -

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-   Imine -

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-   Infrared spectroscopy -

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-   Intermediate -

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-   Isomer - Compounds with the same molecular formula but different
    structural formulae. There are two main forms of isomerism:
    structural isomerism and stereoisomerism.

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-   Isotope - The different types of atoms of the same chemical element,
    each having a different atomic mass (mass number). Isotopes of an
    element have nuclei with the same number of protons (the same atomic
    number) but different numbers of neutrons.

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-   IUPAC - Acronym for International Union of Pure and Applied
    Chemistry.

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-   IUPAC Nomenclature - The international standard set of rules for
    naming molecules.
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## K

-   Kekulé structure -

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-   Keto-enol tautomerism -

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-   Ketone - The functional group characterized by a carbonyl group
    (O=C) linked to two other carbon atoms, or a chemical compound that
    contains a carbonyl group

## L

-   Leaving group -

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-   Levorotatory -

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-   Lewis acid - A reagent that accepts a pair of electrons form a
    covalent bond. *(see also Lewis Acids and
    Bases)*

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-   Lewis base - A reagent that forms covalent bonds by donating a pair
    of electrons. *(see also Lewis Acids and
    Bases)*

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-   Lewis structure -

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-   Lindlar catalyst -

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-   Line-bond structure -

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-   Lone pair electrons -

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-   LUMO - Acronym for Lowest Unoccupied Molecular Orbital

## M

-   Markovnikov\'s
    rule -
    States that \"when an unsymmetrical alkene reacts with a hydrogen
    halide to give an alkyl halide, the hydrogen adds to the carbon of
    the alkene that has the greater number of hydrogen substituents, and
    the halogen to the carbon of the alkene with the fewer number of
    hydrogen substituents.\"

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-   Mass number - The total number of protons and neutrons (together
    known as nucleons) in an atomic nucleus

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-   Mass spectrometry -

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-   Mechanism -

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-   Meso compound -

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-   Meta -

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-   Methylene group -

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-   Molality - A measure of the concentration of a solute in a solvent
    given by moles of solute per kg of solvent.

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-   Molarity - A measure of the concentration, given by moles of solute
    per liter of *solution* (solute and solvent mixed).

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-   Mole - A measure of a substance that is approximately Avogadro\'s
    Number (6.022×10^23^) of molecules of the substance. More simply,
    calculate the molecule\'s atomic mass and that many grams of the
    substance is a mole.

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-   Molecule -

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-   Monomer - A small molecule that may become chemically bonded to
    other monomers to form a polymer.

## N

-   Nitrile - Any organic compound which has a -C≡N functional group.

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-   NMR - See Nuclear magnetic resonance.

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-   Non-bonding electrons -

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-   Normality -

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-   Nuclear magnetic resonance -

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-   Nucleophile - Literally, nucleus lover. A negatively or neutrally
    charged reagent that forms a bond with an electrophile by donating
    both bonding electrons. Nucleophiles are Lewis Bases.

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-   Nucleophilic addition reaction -

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-   Nucleophilic aromatic substitution reaction -

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-   Nucleophilic substitution
    reaction -
    A reaction in which a halide is removed from a molecule and replaced
    with a nucleophile.

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-   Nucleophilicity -

## O

-   Optical isomer -

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-   Optical activity -

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-   Orbital -

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-   Ortho -

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-   Oxidation -

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-   Oxime -

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-   Oxymercuration reduction reaction -

## P

-   Para -

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-   Pauli exclusion principle -

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-   Pericyclic reaction -

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-   Periplanar -

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-   Peroxide -

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-   Peroxyacid -

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-   Phenol - A toxic, colourless crystalline solid with the chemical
    formula C~6~H~5~OH and whose structure is that of a hydroxyl group
    (-OH) bonded to a phenyl ring. It is also known as carbolic acid,

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-   Phenyl - A functional group with the formula -C~6~H~5~

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-   Pi bond -

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-   Polar aprotic solvent -

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-   Polar covalent bond -

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-   Polar protic solvent -

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-   Polar reaction -

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-   Polarity -

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-   Polarizability -

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-   Polymer - A large molecule (macromolecule) composed of repeating
    structural units (monomers) typically connected by covalent chemical
    bonds.

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-   Primary -

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-   Prochiral -

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-   Prochirality center -

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-   Protic solvent -

## Q

## R

-   R group -

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-   R,S convention -

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-   Racemic mixture -

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-   Radical -

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-   Radical reaction -

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-   Rate constant -

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-   Rate equation -

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-   Rate-limiting step -

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-   re face -

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-   Reducation -

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-   Regiochemistry -

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-   Regioselectivity -

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-   Resonance form -

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-   Resonance hybrid -

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```
-   Ring-flip -

## S

-   Saponification - The hydrolysis of an ester under basic conditions
    to form an alcohol and the salt of a carboxylic acid.

```{=html}
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```
-   Saturated - Saturation in a general means possessing a maximal
    quantity. A compound is commonly called saturated when it has no
    double or triple bonds. Saturated can refer to a maximal amount of a
    solute which can dissolve in a solution. Whether the context is
    chemical bonding or solutions will determine which meaning is
    appropriate.

```{=html}
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```
-   Saytzeff\'s Rule - See Zaitsev\'s
    rule

```{=html}
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```
-   Second order reaction - A reaction whose rate is dependent on the
    concentration of two reactants, leading to a reaction rate of
    $Rate = k[X][Y]$

```{=html}
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```
-   Secondary -

```{=html}
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```
-   si face -

```{=html}
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```
-   Side chain -

```{=html}
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```
-   Sigma bond -

```{=html}
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```
-   Simmons-Smith reaction -

```{=html}
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```
-   S~N~1 reaction -

```{=html}
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```
-   S~N~2 reaction -

```{=html}
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```
-   Solvation -

```{=html}
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```
-   Solvent -

```{=html}
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```
-   sp orbital -

```{=html}
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```
-   sp^2^ orbital -

```{=html}
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```
-   sp^3^ orbital -

```{=html}
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```
-   Spin-spin splitting -

```{=html}
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```
-   Staggered conformation -

```{=html}
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```
-   Stereochemistry -

```{=html}
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```
-   Stereoisomer -

```{=html}
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```
-   Steric hinderance -

```{=html}
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```
-   Steric strain -

```{=html}
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```
-   Substitution reaction - Reactions where one functional groups is
    replaced with another functional group.

```{=html}
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```
-   Symmetry plane -

```{=html}
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```
-   Syn addition -

```{=html}
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```
-   Syn periplanar -

## T

-   Tautomers -

```{=html}
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```
-   Tertiary - adjective describing a third occurrence or position

```{=html}
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```
-   Thioester -

```{=html}
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```
-   Thiol - A compound that contains the functional group composed of a
    sulfur atom and a hydrogen atom (-SH).

```{=html}
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```
-   Thiolate ion -

```{=html}
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```
-   Torisional strain -

```{=html}
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```
-   Tosylate -

```{=html}
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```
-   Transition state -

```{=html}
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```
-   Twist-boat conformation -

## U

-   Ultraviolet spectroscopy -

```{=html}
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```
-   Unsaturated - Unsaturated commonly describes a situation in which a
    compound contains double or triple bonds.

```{=html}
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```
-   Upfield - A term used to describe the right direction on NMR charts.
    A peak to the right of another peak is described as being upfield
    from the peak.

## V

-   Valence bond theory -

```{=html}
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```
-   Valence electrons -

```{=html}
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```
-   Valence shell -

```{=html}
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```
-   Van der Waals forces -

```{=html}
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```
-   Vicinal -

```{=html}
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```
-   Vinyl - An organic compound that contains a vinyl group (also called
    ethenyl), −CH=CH2.

```{=html}
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```
-   Vinylic -

## W, X, Y, Z

-   Zaitsev\'s
    rule -
    In elimination
    reactions,
    the major reaction product is the alkene with the more highly
    substituted double bond. This most-substituted alkene is also the
    most stable.

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-   Zussamen - German word meaning \"together\". Represented by Z in the
    E/Z naming system of alkenes. Simple mnemonic, Z=Zame Zide (Same
    Side).


# Organic Chemistry/Periodic table

+----------------------+----------------------+----------------------+
| `<span style="       | \                    | ``{=htm |                      | color:green;">`{=htm |
| l}1`</span>`{=html}\ |                      | l}2`</span>`{=html}\ |
| **H**                |                      | **He**               |
+----------------------+----------------------+----------------------+
| 3\                   | 4\                   | 5\                   |
| **Li**               | **Be**               | **B**                |
+----------------------+----------------------+----------------------+
| 11\                  | 12\                  | 13\                  |
| **Na**               | **Mg**               | **Al**               |
+----------------------+----------------------+----------------------+
| \                    | ``{=html |                      |
|                      | }35`</span>`{=html}\ |                      |
|                      | **Br**               |                      |
+----------------------+----------------------+----------------------+

------------------------------------------------------------------------

Some of the good news about organic chemistry is that it focuses on a
subset of the periodic table, so there are fewer elements to worry
about. These are the main elements with which we must concern ourselves,
although occasionally a few others will be used in reactions.

------------------------------------------------------------------------

Organic chemistry \> Periodic table


# Organic Chemistry/Templates

![](Go_To_Organic_Chemistry_Contents.png "Go_To_Organic_Chemistry_Contents.png")

------------------------------------------------------------------------

## Review table

+----------------+
| ```{=html}     |
| <center>       |
| ```            |
| ```{=html}     |
| <H1>           |
| ```            |
| Header         |
|                |
| ```{=html}     |
| </H1>          |
| ```            |
| ```{=html}     |
| </center>      |
| ```            |
| body goes here |
+----------------+

## Note table

+-----------------------+
| ## Note               |
|                       |
| note contents go here |
+-----------------------+

## Equations

+---------------------------+
| ## Title                  |
|                           |
| CH~4~ Br^-^ → No reaction |
+---------------------------+


# Blender 3D: Noob to Pro/Glossary

|previous=Intro-GE-Source
|subcat=Reference
}}
```
## A

-   **Alpha Channel** is an additional channel in a 2D image for
    transparency. In an image element which stores a color for each
    pixel, an additional value is stored in the alpha channel containing
    a value between 0 and 1. A value of 0 means that the pixel does not
    have any coverage information; i.e. there was no color contribution
    from any geometry because the geometry did not overlap this pixel. A
    value of 1 means that the pixel is fully opaque because the geometry
    completely overlapped the pixel.

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```
-   **Ambient Light** is light that doesn\'t seem to come from a
    specific source, but is just there. Look under the desk - it\'s
    pretty dark, but there\'s some light there. In the real world, this
    is caused by stray photons bouncing around and occasionally
    ricocheting under the desk. Ambient light is the basic, minimal
    amount of light in the whole scene. Adding too much ambient light
    makes a scene look washed out. Since the light doesn\'t come from
    anywhere, all sides of an object are illuminated equally, and it
    won\'t have any shading on it.

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```
-   **Ambient Occlusion** (AO) is a ratio of how much ambient light a
    surface point would be likely to receive. It simulates a huge dome
    light surrounding the entire scene. If a surface point is under a
    foot or table, it will end up much darker than the top of someone\'s
    head or the tabletop.

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```
-   **Armature** is the interconnection of bones that form the skeleton
    of an animated figure. The Inverse Kinematics library contains the
    code to make armatures move. The armature must still be rigged with
    3D objects to give shape to its head, hands, trunk, feet, etc.

## B

-   **Background image**: a 2D image (\"picture\") that is placed
    \"behind\" the entire 3D scene, like a backdrop on a movie set.
    Blender permits the placement of these images in all six directions
    from the origin: back, front, top, bottom, left, right.
-   **Bake**: to precompute computationally-intensive elements of an
    animation. For example, in a physics simulation involving the
    behaviour of fluids or clothing, you would set up the physical
    parameters, then compute (*bake*) the positions and shapes of the
    objects over the duration of the animation. Afterwards, you can
    assign materials and lighting, and then render the frames to produce
    the actual animation. Doing the baking as a separate step, and
    saving the results from that, means you can change your mind about
    the materials and lighting and rerender the frames more quickly.
-   **Bézier surfaces** were first described in 1972 by the French
    engineer Pierre Bézier who used them to design automobile bodies.
    Bézier surfaces can be of any degree, but bicubic Bézier surfaces
    generally provide enough degrees of freedom for most applications.

```{=html}
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```
-   **BF** is Blender Foundation

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```
-   **Blend** - *to Blend*, working with Blender; also Blender\'s file
    extension.

```{=html}
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```
-   **Bounce Light**: Simple lighting situations have a single light,
    called a key light, illuminating one side of an object. This creates
    strong shading and definition of the volume of the object. However,
    a 3D light will often make the contrast too great - the dark side of
    the object is completely black since no light is hitting it. In
    reality it would still be lit a little, just not as much as the
    brightly lit side, because of light bouncing around the room and
    hitting the dark side of the object. In realtime 3D, bounce light is
    not calculated, so you have to create it yourself. Either add a
    little ambient color, or put a second, less bright directional light
    pointing the opposite direction to give a little light to the
    shadows.

```{=html}
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```
-   **Bump mapping** is a technique where at each pixel, a perturbation
    to the surface normal of the object being rendered is looked up in a
    texture map and applied before the illumination calculation is done.
    Bump Mapping use a gray-scale image map to change the direction of
    surface normals. You can use this to simulate height, so that you
    can paint wrinkles and bumps. 50 % grey means neutral (no change is
    made), lighter means higher, darker means lower. Note that the
    position of faces is not actually changed; by rotating just the
    normals, lighting will change too, to give the illusion of a height
    difference. This has downsides too: the outline of objects isn\'t
    changed, so the trick is given away. For similar effects you can use
    Displacement Mapping and Normal Mapping.

## C

-   **Caustics** in optics is a bundle of light rays. For example a
    caustic effect may be seen when light refracts or reflects through
    some refractive or reflective material, to create a more focused,
    stronger light on the final location. Such amplification, especially
    of sunlight, can burn --- hence the name. A common situation when
    caustics are visible is when some light points on glass. There is a
    shadow behind the glass, but also there is a stronger light spot.
    Nowadays, almost every advanced rendering system supports caustics.
    Some of them even support volumetric caustics. This is accomplished
    by raytracing the possible paths of the light beam through the
    glass, accounting for the refraction, reflection, etc.
-   **CG** is Computer Graphics
-   **CGI** is Computer Generated Imagery

## D

-   **Depth of Field** (DOF) is the
    distance in front of and behind the subject which appears to be in
    focus. For any given lens setting, there is only one distance at
    which a subject is precisely in focus, but focus falls off gradually
    on either side of that distance, so there is a region in which the
    blurring is tolerable. This region is greater behind the point of
    focus than it is in front, as the angle of the light rays change
    more rapidly; they approach being parallel with increasing distance.

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```
-   **Diffuse Light** is even, directed light coming off a surface. For
    most things, the diffuse light is the main lighting we see. Diffuse
    light comes from a specific direction or location, and creates
    shading. Surfaces facing towards the light source will be brighter,
    while surfaces facing away from the light source will be darker.

```{=html}
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```
-   **Directional Light** is a light that has a specific direction, but
    no location. It seems to come from an infinitely far away source,
    like the sun. Surfaces facing the light are illuminated more than
    surfaces facing away, but their location doesn\'t matter. A
    Directional Light illuminates all objects in the scene, no matter
    where they are.

```{=html}
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```
-   **Displacement Mapping** uses a
    greyscale heightmap, like Bump Mapping, but the image is used to
    physically move the vertices of the mesh at render time. This is of
    course only useful if the mesh has large amounts of vertices, but
    the (relatively) new \"Simple Subdiv\" subsurf option allows you to
    add more vertices at render time which will be moved by the
    displacement. This makes it much slower than Bump Mapping, as there
    need to be many more faces to render, but it is much more realistic.

## E

-   **Environment Maps** (EnvMaps) is the method of calculating
    reflections. Involved rendering images at strategic positions and
    applying them as textures to the mirror. Now in most cases obsoleted
    by Raytracing, which though slower is easier to use and more
    accurate.

## F

-   **Focal Length** of a lens is the
    distance along the optical axis from the lens to the focus (or focal
    point). The inverse of a lens\' focal length is called its power.

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-   **Focus "wikilink")** of a lens is the point onto
    which collimated light parallel to the axis is focused.

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-   **Foreshortening**

```{=html}
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-   **Fresnel** lens is a type of
    lens invented by Augustin-Jean Fresnel. Originally developed for
    lighthouses, the design enables the construction of lenses of large
    size and short focal length without the weight and volume of
    material which would be required in a lens of conventional design.
    As it relates to rendering, fresnel refers to the tendency of
    materials to be more reflective when light strikes at a high angle
    of incidence\-- think of how sunlight reflects from distant water,
    but penetrates closer water, or of how road glare is most extreme at
    dawn or dusk. This varies with material, and specification of
    fresnel is an important part of material definition.

## G

-   **GE** is Game Engine.

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```
-   **Global Illumination** (GI) is
    a superset of radiosity and ray tracing. The goal is to compute all
    possible light interactions in a given scene, and thus obtain a
    truly photorealistic image. All combinations of diffuse and specular
    reflections and transmissions must be accounted for. Effects such as
    colour bleeding and caustics must be included in a global
    illumination simulation.

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```
-   **Gouraud shading** is a method used
    in computer graphics to simulate the differing effects of light and
    colour across the surface of an object. In practice, Gouraud shading
    is used to achieve smooth lighting on low-polygon surfaces without
    the heavy computational requirements of calculating lighting for
    each pixel. The technique was first presented by Henri Gouraud in
    1971.

## H

-   **High Dynamic Range
    Image** (HDRI) is a set of
    techniques that allow a far greater dynamic range of exposures than
    normal digital imaging techniques. The intention is to accurately
    represent the wide range of intensity levels found in real scenes,
    ranging from direct sunlight to the deepest shadows. The use of high
    dynamic range imaging in computer graphics has been popularised by
    the work of Paul Debevec. Blender uses Yafray for these techniques.

## I

-   **Index Of Refraction** (IOR) is
    about the way that light passes through different types of
    materials\... diamond, glass, water etc. When a light ray travels
    through the same volume it follows a straight path. However if it
    passes from one transparent volume to another, it bends. This is why
    a straw in water looks bent. The amount of bending differs between
    materials. The angle by which the ray is bent can be determined by
    knowing two things: the angle at which the incoming ray has been
    cast and the Index of Refraction. This IOR value is unique for every
    material. Glass has an IOR of about 1.5 and water 1.3. By increasing
    the IOR value for a Blender material, you can control how much the
    environment behind the transparent object is distorted, and thus
    improving the realism of the shader.

```{=html}
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```
-   **Interpolation** (IPO) is an
    animation curve: it indicates how the object must \"move\" between
    an initial and a final position, at the rate determined by the
    rendering engine. Objects can be animated in many ways. They can be
    animated as Objects, changing their position, orientation or size in
    time; they can be animated by deforming them; that is animating
    their vertices or control points; or they can be animated via very
    complex and flexible interaction with a special kind of object: the
    Armature.

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```
-   **Inverse Kinematics** (IK) is
    the process of determining the movement of interconnected segments
    of a body or model, starting from the desired motion of the
    endpoints of the armature. Using ordinary Kinematics on a
    hierarchically structured object you can for example move the
    shoulder of a puppet. The upper and lower arm and hand will
    automatically follow that movement. IK will allow you to move the
    hand and let the lower and upper arm go along with the movement.
    Without IK the hand would come off the model and would move
    independently in space. The Blender Armature System includes Inverse
    Kinematics. For general armatures there are many possible solutions
    to the IK.

## J

-   **JPEG** Acronym for Joint Photographic Expert
    Group (pronounced jay-peg) is a commonly used standard method of
    lossy compression for photographic images. The file format which
    employs this compression is commonly also called JPEG; the most
    common file extensions for this format are .jpeg, .jfif, .jpg, .JPG,
    or .JPE although .jpg is the most common on all platforms.

## K

-   **Keyframe** is a frame in an animated sequence of frames that was
    drawn or otherwise constructed directly by the user. When all frames
    were drawn by animators, the senior artist would draw these frames,
    leaving the \"in between\" frames to an apprentice. Now, the
    animator creates only the first and last frames of a simple
    sequence; the computer fills in the gap. This is called tweening.

## L

-   **Luminosity** (more properly called
    luminance) is the density of luminous intensity in a given
    direction. In astronomy, luminosity is the amount of energy a body
    radiates per unit time. It is typically expressed in the SI units
    watts, in the cgs units ergs per second, or in terms of solar
    luminosities, Ls; that is, how many times more energy the object
    radiates than the Sun, whose luminosity is 3.827×1026 W.

## M

-   **Motion Blur** is the simulation of the
    phenomenon that occurs when we perceive a rapidly moving object. The
    object appears to be blurred because of our persistence of vision.
    Doing motion blur makes computer animation appear more realistic. It
    can be thought of as adding back some of the time dependence
    expressed in the Rendering Equation.

## N

-   **Nabla**. *Ton wrote:* Almost all procedural
    textures in Blender use derivatives for calculating normals for
    texture mapping (with as exception \"Blend\" and \"Magic). The
    texture normal, the derivative, is calculated by using four samples
    in the texture formula:

`s0= texture(x, y, z)`\
`s1= texture(x+nabla, y, z)`\
`s2= texture(x, y+nabla, z)`\
`s3= texture(x, y, z+nabla)`

`normal[0]= s0-s1`\
`normal[1]= s0-s2`\
`normal[2]= s0-s3 `

Up to now, the \"nabla\" offset was a constant (0.025) which worked fine
in most cases, but doesn\'t give proper control over the way a texture
is sampled, for example to make the effect smoother or sharper. This
feature especially is useful in combination with the ColorBand feature.

-   **Non-Linear Animation** (NLA) allows the animator to edit motions
    as a whole, not just the individual keys. Nonlinear animation is not
    just about editing and manipulating groups of keyframes, but it also
    allows you to combine, mix, and blend motions to create entirely new
    animations.

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```
-   **Nonuniform Rational
    B-Splines** (NURBS) is a
    computer graphics technique for generating and representing curves
    and surfaces.

```{=html}
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```
-   **Normal** (Surface Normal) to a flat surface is a three-dimensional
    vector which is perpendicular to that surface. A normal to a
    non-flat surface at a point p on the surface is a vector which is
    perpendicular to the tangent plane to that surface at p.

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```
-   **Normal Mapping** is similar to Bump Mapping, but instead of the
    image being a greyscale heightmap, the colours define in which
    direction the normal should be shifted, the 3 colour channels being
    mapped to the 3 directions X, Y and Z. This allows more detail and
    control over the effect.

## O

-   **Orange** is the first Blender open
    movie project.

```{=html}
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```
-   **Oversampling** (OSA), also called **Anti-Aliasing** is the
    technique of minimizing aliasing when representing a high-resolution
    signal at a lower resolution. In most cases, anti-aliasing means
    removing data at too high a frequency to represent. When such data
    is left in a signal, it causes unpredictable artifacts.

## P

-   **Phong** shading term is used indiscriminately to describe both an
    illumination model and an interpolation method in 3D computer
    graphics. Phong reflection is a local illumination model and can
    produce a certain degree of realism in three-dimensional objects by
    combining three elements - diffuse, specular and ambient for each
    considered point on a surface. It has several assumptions - all
    lights are points, only surface geometry is considered, only local
    modelling of diffuse and specular, specular colour is the same as
    light colour, ambient is a global constant.

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```
-   **Point Light** is a light that has a specific location and radiates
    equally out in all directions. Examples of point lights would be
    candles or bare lightbulbs. Surfaces close to the point light are
    brighter than those which are far away. Point lights have
    attenuation, which controls how quickly the light intensity drops
    off as you move away from it. Lights with high attenuation are very
    localized, while lights with low attenuation will spread farther.

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```
-   **Polygonization** *(of meta-surfaces)* is the process of
    approximating the meta-surface via polygons so it can be
    displayed/rendered in Blender.

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```
-   **Purple** runs as a normal Verse client. It implements a node
    database to mirror the contents of its host. It loads the plug-ins,
    which reside in libraries, from local disk as DLLs or shared objects
    depending on the platform.

## Q

-   **Quaternion** is a representation of 3D
    rotations with four numbers. It can be interpreted as an extension
    of complex numbers to 3D. The interpretation of the four numbers is
    not very intuitive for a human, but the numerical advantage of
    quaternions is that it is the smallest mathematical representation
    that does not suffer from the gimbal
    lock
    singularity problem. This
    problem occurs for example with Euler
    angle representations, when a small
    change in the 3D orientation can give rise to a large change in
    Euler angles.

## R

-   **Radiosity** is a more accurate but also more process-intensive
    technique than raytracing, that calculates patterns of light and
    shadow for rendering graphics images from three-dimensional models.
    One of the many different tools which can simulate diffuse lighting
    in Blender.

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-   **Raytracing** works by tracing the path taken by a ray of light
    through the scene, and calculating reflection, refraction, or
    absorption of the ray whenever it intersects an object in the world.
    More accurate than Scanline, but much slower.

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-   **Render**: to generate actual viewable images from a 3D model or
    scene. This may or may not need to happen in real time; for example
    an interactive game requires real-time rendering, whereas a feature
    film does not. These situations require very different rendering
    techniques.

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-   **Refraction** in geometric optics is the change in direction of a
    wave due to a change in velocity. It happens when waves travel from
    a medium with a given refractive index to a medium with another. At
    the boundary between the media the wave changes direction; its
    wavelength increases or decreases but frequency remains constant.
    For example, a light ray will refract as it enters and leaves glass.

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```
-   **Relative Vertex Keys** (RVK) are part of a keyframe animation
    system that operates on vertex level objects. Each (shape) key is
    stored as a morph target such that several keys may be blended
    together to achieve complex mesh animation. With RVK you can create
    facial expressions, speech, and other detailed animated keyframed
    movements within your mesh-based models.

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```
-   **Rig:** the controls that aid in the manipulation of a digital
    character.

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-   **Rigging** is the process by which a person creates constraints and
    relationships between objects that will generate controls to aid in
    the manipulation of a digital character.

## S

-   **Scanline** is one row of pixels in the final render. Also the term
    for one of the methods of rendering which Blender can use. It is
    much faster than Raytracing, but allows fewer effects, such as
    reflections, refractions, motion blur and focal blur.

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-   **Seed**: a starting number for generating a random-looking number
    sequence. Using the same seed will always give you the same
    sequence. Technically, such a sequence is not truly random, it is
    only *pseudorandom*.

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-   **Shader**: an algorithm for computing the appearance of a given
    material based on the colour, angle and intensity of the light.
    *Specular* shaders produce a more shiny, mirrorlike finish, while
    *diffuse* shaders give a duller surface appearance. There are also
    *toon* shaders, which are deliberately designed to produce an effect
    more akin to a cartoon drawing, with delineated object borders and
    less gradation of colours over a surface.

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-   **Shadows**: simulated lights don\'t normally cast shadows. And,
    they also pass through solid objects - so a light inside a closed
    box would actually illuminate things outside the box as if the box
    were transparent. The shading on objects is only calculated based on
    the angle of the surface.

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-   **Specular Light** refers to the highlights on reflective objects,
    like diamonds, billiard balls, and eyes. Specular highlights often
    appear as bright spots on a surface, at a point where the light
    source hits it directly. Ambient, Diffuse, and Specular are called
    the three components of a light source. Each one is given a color,
    which, when added together, create the final color of a light. For
    most lights, the main overall color of the light is defined by the
    Diffuse color. Sunlight or lightbulbs would be white, while
    moonlight would be a darker blue, and a candle would be yellow. You
    can use the ambient color to adjust the overall color range of the
    light source; or, you can get a slight tint to shadows by making the
    diffuse component yellow and the ambient a slight blue. In many
    lights, the ambient color is left at black, meaning that it won\'t
    have any effect. Specular components are often left at white, but
    you can make them different colors to get interesting effects. Most
    of the time you can completely ignore the specular and diffuse
    settings on a light, but just be aware that the way you set the
    color is by specifically setting the diffuse color. The final color
    that an object appears to be is a combination of the light hitting
    it and the color of the surface.

```{=html}
<!-- -->
```
-   **Spotlight** is a light with both location and direction. A
    spotlight sends out a cone of light defined by the spotlight angle,
    and illuminates only objects within that cone. Spotlights also have
    attenuation, as well as a parameter that controls whether the spot
    of light is sharply defined or has smooth edges. These 4 types of
    lights are listed in order of computational complexity; the more
    lights you have, the more work the computer has to do. Generally
    it\'s a good idea to use directional lights whenever possible, since
    they\'re the cheapest, and use pointlights and spotlights sparingly.

```{=html}
<!-- -->
```
-   **Stucci** is one of the classes of blender textures. *Stucci* is
    not an English word, but is used in Blender as the plural of
    stucco.

```{=html}
<!-- -->
```
-   **Subdivision Surface** (Subsurf) is the tool which subdivides your
    model at render-time, without affecting your mesh at design-time.
    There are two subsurf algorithms in Blender to choose from - *Simple
    Subdiv*, which doesn\'t affect the shape of your mesh, and is used
    to add detail to displacement mapping or render-time radiosity, both
    of which operate on a per-vertex basis. The other is
    *Catmull-Clark*, a common subdivision algorithm which smooths out
    curves, and allows you to make complicated smooth surfaces (e.g.
    people, plants, etc.) with very few faces. However this algorithm
    can sometimes (read: often) have strange results with meshes
    containing triangles or vertices with many edges (\"poles\"), unless
    it is correctly handled.

```{=html}
<!-- -->
```
-   **Sub Surface Scattering** (SSS) is a mechanism of light transport
    in which light penetrates the surface of a translucent object, is
    scattered by interacting with the material, and exits the surface at
    a different point. All non-metallic materials are translucent to
    some degree. In particular, materials such as marble, skin, and milk
    are extremely difficult to simulate realistically without taking
    subsurface scattering into account.

## T

-   **Tuhopuu** is an experimental version of Blender that is like a
    code playground, developers can put their new code in there to be
    tested and played with by users before it gets put into the official
    Blender. Tuhopuu is Finnish for \"Tree of destruction\".

```{=html}
<!-- -->
```
-   **Tweening** is short for in-betweening, the process of generating
    intermediate frames between two images to give the appearance that
    the first image evolves smoothly into the second image. Tweening is
    a key process in all types of animation, including computer
    animation. Sophisticated animation software enables one to identify
    specific objects in an image and define how they should move and
    change during the tweening process. Another word for tweening is
    interpolation.

## U

-   **UV Mapping** (UV) This refers to the process of re-parameterizing
    a 3d object with dimensions x, y and z into a 2d plane with
    coordinates u and v. Most texturing requires this step because it
    tells the program HOW to apply a 2d image map onto a 3d object. If
    all your textures must be 2d and flat, the easiest way to determine
    what pixel goes where is if your model is flattened and made 2d. It
    also establishes a relationship between a 2d image and the mesh such
    that if the mesh deforms, the image map will deform along with it.
    Think of it as skinning a cat and pinning its hide onto cardboard to
    facilitate painting it!

## V

-   **Verse** is a network protocol that lets multiple applications act
    together as one large application by sharing data over a network. If
    one application makes a change to shared data, the change is
    distributed instantly to all the other interested clients.

## W

-   **WC** is Weekend Challenge.

```{=html}
<!-- -->
```
-   **WIP** is Work In Progress.

## X

## Y

-   **Yet Another Free Raytracer** (YafRay) is an open source ray
    tracing program that uses an XML scene description language. It has
    been integrated into, and is often used to render scenes made in,
    Blender.

## Z


# Blender 3D: Noob to Pro/Unit 1: Knowing Before Making

|previousFull=Blender 3D: Noob to Pro
|subcat=Background
}}
```
Blender is a powerful and complex 3D modeling and rendering package.
However, before you can make anything, you need to understand several
concepts used in 3D modelling and related fields. Examples include:

-   Understanding the process of 3D modeling and rendering
-   Understanding how the axis and 3D coordinates work in Blender.
-   Understanding orthographic and perspective views.
-   Local coordinates, parent objects, and child objects.
-   Blender\'s user interface and how to navigate it.
-   Viewing a scene from different camera angles

Don\'t be scared by their long names; a lot of these are actually pretty
intuitive and easy to grasp. Of course, since you\'re not doing any
actual modelling in this unit, you might be tempted to skip ahead, and
that\'s completely fine! Just know that understanding these concepts
well will help you a lot in the long run, and proceeding through
tutorials in order will build a strong foundation for you to build on.
Prior knowledge also plays a huge part in this, so if you\'re coming
from other 3D software, you should already be familiar with these
concepts.

That said, the actual fun (making stuff in Blender) comes in the next
unit. However, keep in mind that Blender is not the kind of software you
can jump into and experiment with. It\'s notorious for having a steep
learning curve. It\'s less like exploring an unfamiliar city and more
like flying a spaceship; if you hop into the pilot\'s seat without
knowing the fundamentals, it\'s going to be near impossible to get off
the ground.

### Blender-specific terminology.

Like any subject, 3D graphics has its own words and terminology used to
describe specific ideas. In this book, important words are
 and defined on their
first use. If you\'ve missed or forgotten the meaning of a word, try
looking it up in the Glossary.

### Things you\'ll need.

In order to follow the tutorials, you need a computer with Blender
installed. You can download the latest Blender release
here.

Depending on your system, you may also need the appropriate Python
installation. Each version of Blender requires a specific version of
Python, but it\'s usually packaged with Blender.

The Blender team has the Blender Long Term Support program which
provides a stable Blender version with 2 years of support. During the 2
year support window, no new features, UI changes, API changes or other
enhancements will be done; only critical fixes will be applied. This
allows teams working on long-lasting blender projects to use a single
supported version over a 2 year period. Long term versions are indicated
below with the LTS suffix and a year indicating the last year of
support.

  Blender version   Python version
  ----------------- ----------------
  2.79              3.5
  2.83 LTS 2022     3.7
  2.90              3.7
  2.93 LTS 2023     3.9
  3.0               3.9
  3.1               3.10
  3.3 LTS 2024      3.10
  3.4               3.10

You can check Python version on Scripting workspace using:

``` python3
import sys
print(sys.version)
```

Since Blender is open-source software, you can download the source code
and build it yourself, but it\'s easier to download a pre-built binary.
As of Blender 3.4.1, compiled releases are provided for the following
operating systems:

-   Windows 8.1, 10, and 11
-   macOS 10.13 Intel · 11.0 Apple Silicon
-   Linux

Along with the website, many Linux distributions have Blender available
in their package repositories, though it may be a slightly older
version. You can use your system\'s package manager to download and
install the package. It\'s also available on steam.

Windows users can also choose between an executable installer (\"setup
wizard\") and a ZIP archive.

After the installation process is finished, Blender should appear in the
Graphics section of your desktop environment application menu.

You may also want to download a 2D image editor, such as GIMP,
Paint.NET, or Photoshop or a media player, such as VLC.

It\'s a good idea to have pencil and paper handy for sketching and
taking notes. There\'s a lot to absorb. Taking notes as you go will pay
dividends later.

### Where to Go for Help

If you get stuck, you can ask for help from other Blender
users in the
appendices.

## Additional Resources

Many modules have a section like this at the bottom, listing websites
with information on the topics covered in the module.

-   Blender system
    requirements

ko:블렌더_3D_배우기/만들기_전에_알아야할_것


# Blender 3D: Noob to Pro/What Blender Can Do

|next=3D Geometry
|subcat=Background
}}
```
In this module, you\'ll learn what Blender does, both in terms of the
product (images) and the process (3D modeling).

\_\_TOC\_\_ Blender is a free software
package for authoring \"three-dimensional\" (3D) graphics (also known as
*computer graphics* or "CG"), including still images, games, and video.

While the end-product of most Blender projects is a two-dimensional (2D)
raster image on a flat surface (be it a monitor, movie screen, or sheet
of paper) except for Head Mounted Virtual Reality applications, the
images are said to be \"3D\" because they exhibit the
. In other words,
someone looking at the image can easily tell which parts are meant to be
closer and which are farther away.

## An Example

Here\'s a realistic still image that was created with Blender. !\"A
Lonely House\", by
Mayqel{width="400"}

Look closely at the building.

-   Because it is obscured by the building, you can tell that the
    tree-lined hillside is *behind* the building instead of vice versa.
-   The way the top and bottom edges of the front wall appear to
    converge toward the base of the tree allow you to judge the angle
    between the front wall and your viewpoint.
-   Your brain interprets dark portions of the wall as shadows, allowing
    you to estimate where the light is coming from, even though the sun
    is outside the frame of the image.

While an illusion of depth can be authored by hand with 2D graphics
software (or a paintbrush!), Blender provides a much easier way.

It\'s likely that the lonely house never existed outside of the
artist\'s mind. Instead of building a big set on a rural lot in Germany,
waiting for the right light, and photographing it, the author built a
scene in a virtual 3D world---one contained inside a computer. This is
called CGI (Computer Generated Imagery). They then used Blender to
 the scene (convert it into a
2D image). You can view more of what Blender can do at the Blender
gallery: <http://www.blender.org/features/>

## Steps in the 3D Production Process

To produce an image like the one above involves two major steps to start
with:

-       , which is the creation of your miniature 3D world, also known as a
     or
    . This involves defining the
    geometry of the objects, making it look like they are made out of
    particular , setting up
    the , and defining a
     viewpoint.

-       , which is the actual generation of the image of the world from the
    viewpoint of the camera (taking a "photograph" of the scene, if you
    like), for your audience to enjoy.

3D is often used to produce not just single still images, but
 as well. This requires
some additional steps:

-       --- setting up a , namely a
    way of  (changing the
    shape of) a character in various repeatable ways to convincingly
    mimic joint movements, facial expressions and other such actions of
    real-life people or animals.

-       --- choreographing the positions of the objects and their parts in
    the 3D scene over time, using the previously-created animation rigs

-   Rendering now involves creating a whole
     of frames representing
    movement over time, rather than just a single still frame.

But that's not all. There are frequently additional processes to
embellish the results of the above, to make them look more realistic:

-       --- a more organic form of modelling objects by shaping them as
    though they were made out of clay. This produces more complicated,
    irregular shapes which mimic real objects found in nature, as
    opposed to clean, simple, geometrical ones which mostly only exist
    in the world of mathematics.

-       --- You're probably familiar with programs that let you paint an
    image on a 2D digital canvas. Such programs are commonly used in 3D
    production, to create
    which are "wrapped" around the surfaces of 3D objects to give them a
    more interesting appearance. 3D programs also often allow direct
    painting on the surfaces of those objects, so the effect of the
    design can be observed immediately, instead of having to go through
    a separate paint-on-a-flat-surface-then-wrap sequence of steps.

-       --- simulating the behaviour of real-world objects subject to
    real-world forces, for example hard balls colliding, soft cloth
    draping itself over an obstacle under gravity, water flowing and
    pouring. Mathematical formulas are available for these that give
    results very close to real life, all you need is the computing power
    to calculate them.

-       , or : producing convincing
    animations, particularly ones that look like the movements of real
    people (walking, running, dancing etc) can be hard. Hence the
    technique of capturing the motions of live actors, by filming them
    with special markers attached to strategic points on their bodies,
    and doing computer processing to track the movements of these
    markers and convert them to corresponding movements of an animation
    rig.

-       --- this is where 3D renders are merged together with real
    photographic/live-action footage, to make it look like a rendered
    model is in the middle of a real-world scene, or conversely a real
    live actor is in the middle of a rendered scene. If done with proper
    skill, in particular due care to matching the effects of lights and
    shadows, the viewer becomes unable to tell what is real and what is
    not!

And just to add another complication to the mix, there are two kinds of
rendering:

-       rendering is rendering that has to happen under tight time
    constraints, typically for interactive applications like video
    gaming. For example, most gamers expect the screen to be updated 60
    times per second in order to render smooth motion and respond
    quickly enough to player actions. These time constraints impose
    major limitations on the kinds of rendering techniques that can be
    used.

-       rendering is where the time constraints are not so tight, and
    quality is the overriding factor. For example, when producing a
    single still frame, it may not matter so much that it takes minutes
    or hours to do so, because the beauty and detail of the final image
    is worth it. When rendering a Hollywood-quality movie, it may still
    take hours per frame, but the use of a
     of hundreds or
    thousands of machines, all working on different frames at the same
    time, allows the entire sequence to complete in just a few weeks.

**But wait, there's more:** There are also some areas, which might be
considered to be stepping outside of traditional 3D production work,
where Blender provides functionality:

-   **Video editing** --- having rendered your animation sequences and
    shot your live-action footage, you will want to combine them in a
    properly-timed linear sequence to tell a coherent story.
-   **3D printing** --- Many people are
    interested in creating physical objects using 3D printers. The shape
    data may be obtained from real objects with 3D scanning, or it may
    be created from scratch using 3D modelling, or you can even combine
    both processes.

Blender is a capable tool for every single one of these processes.
There's quite a lot there, isn't there? But don't be too intimidated:
this Wikibook will take things step by step, and you will be able to
produce some fun stuff from early on.

## Additional Resources

-
-
-
-
-
-   Blender Art
    Gallery

-   Blender Homepage


# Blender 3D: Noob to Pro/3D Geometry

|previous=What Blender Can Do
|subcat=Background
}}
```
\_\_TOC\_\_

If you haven\'t previously studied 3D graphics, technical drawing, or
analytic geometry, you are about to learn a new way of visualizing the
world, an ability that\'s fundamental to working with Blender or any 3D
modeling tool.

3D modeling is based on , the
branch of mathematics concerned with spatial relationships, specifically
, which expresses
these relationships in terms of algebraic formulas. If you have studied
geometry, some of the terminology will be familiar.

## Coordinates And Coordinate Systems

Look around the room you're in. The odds are it will have a cuboidal
shape, with four vertical walls at right angles to each other, a flat,
horizontal floor, and a flat, horizontal ceiling.

Now imagine there's a fly buzzing around the room. The fly is moving in
three-dimensional space. In mathematical terms, that means its position
within the room at any given moment, can be expressed in terms of a
unique combination of three numbers.

There are an infinite number of ways ---*coordinate systems*--- in which
we could come up with a convention for defining and measuring these
numbers, i.e. the *coordinates*. Each convention will yield different
values even if the fly is in the same position. Coordinates only make
sense with reference to a specific coordinate system! To narrow down the
possibilities (in a purely arbitrary fashion), let us label the walls of
the room with the points of the compass: in a clockwise direction,
North, East, South and West. (If you know which way really is north,
feel free to use that to label the walls of your room. Otherwise, choose
any wall you like as north.)

Consider the point at floor level in the south-west corner of the room.
We will call this (arbitrary) point the *origin* of our coordinate
system, and the three numbers at this point will be $(0, 0, 0)$. The
first of the three numbers will be the distance (in some suitable units,
let's say metres) eastwards from the west wall, the second number will
be the distance north from the south wall, and the third number will be
the height above the floor.

Each of these directions is called an *axis* (plural: *axes*), and they
are conventionally labelled X, Y and Z, in that order. With a little bit
of thought, you should be able to convince yourself that every point
within the space of your room corresponds to exactly one set of
$(x, y, z)$ values, and that every possible combination of $(x, y, z)$
values, with $0 \le x \le W$, $0 \le y \le L$ and $0 \le z \le H$ (where
$W$ is the east-west dimension of your room, $L$ is its north-south
dimension, and $H$ is the height between ceiling and floor) corresponds
to a point in the room.

The following diagram illustrates how the coordinates are built up,
using the same colour codes that Blender uses to label its axes: red for
X, green for Y and blue for Z (an easy way to remember this if you\'re
familiar with RGB is the order \-- Red X, Green Y, Blue Z). In the
second picture, the *x* value defines a plane parallel to the west wall
of the room. In the third picture, the *y* value defines a plane
parallel to the south wall, and in the fourth picture, the *z* value
defines a plane parallel to the floor. Put the planes together in the
fifth picture, and they intersect at a unique point.

![](BlenderCoordinates.png "BlenderCoordinates.png"){width="800"}

Another simple way to understand what the coordinates of a point say
(x,y,z) means is, if one starts from origin and moves x, y, and z units
of distance parallel to x, y, and z axes respectively, in any sequence,
one will reach that point. Thus, for example, a coordinate of (3,4,5)
means the point which is reached when one moves, starting from origin, 3
units of distance along x-axis, 4 units of distance along y-axis and 5
units of distance along z-axis.

This style of coordinate system, with the numbers corresponding to
distances along perpendicular axes, is called *Cartesian coordinates*,
named after René Descartes, the 17th-century mathematician who first
introduced the concept. Legend has it that he came up with the idea
after watching a fly buzzing around his bedroom!

There are other ways to define coordinate systems, for example by
substituting direction angles in place of one or two of the distance
measurements. These can be useful in certain situations, but usually all
coordinate systems in Blender are Cartesian. However, in Blender,
switching between these coordinate systems is simple and easy to do.

### Negative Coordinates

Can coordinate values be negative? Depending on the situation, yes. Here
we are only considering points within our room. But suppose instead of
placing our origin in the bottom southwest corner, we put it in the
middle of the room, halfway between the floor and ceiling. (After all,
it is an arbitrary point, we can place it wherever we like, as long as
we agree on its location.) If the X-coordinate is the distance *east*
from the origin, how do we define a point *west* of the origin? We
simply give it a negative X-coordinate. Similarly, points north of the
origin have a positive Y-coordinate, those south of it, have negative
Y-coordinates. Points above the origin have a positive Z-coordinate,
those below it, a negative Z-coordinate.

### Handedness Of Coordinate Systems

It is conventional for most Cartesian coordinate systems to be
*right-handed*. To understand this, hold the thumb, index finger and
middle finger of your right hand perpendicular to each other: !**Figure
1:** The three axes form a right-handed
system{width="200"}
Now orient your hand so your thumb points along the X-axis in the
positive direction (direction of increasing coordinate numbers), your
index finger along the positive Y-axis, and your middle finger along the
positive Z-axis. Another way of looking at it is, if you placed your eye
at the origin, and you could see the three arrows pointing in the
directions of positive X, positive Y and positive Z as in Figure 1, the
order X, Y, Z would go counter clockwise.

!**Figure 2:** Another view of right-handed
system
Another way to visualize this is to make a fist with your right hand,
with your curled fingers towards you. Stick out your thumb directly to
the right (X). Now aim your pointer finger straight up (Y). Finally,
make your middle finger point toward yourself (Z). This is the view from
directly above the origin.

## Axes Of Rotation

Consider a spinning sphere. Every point on it is moving, except the ones
along the axis. These form a motionless line around which the rest of
the sphere spins. This line is called the *axis of rotation*.

More precisely, the axis of rotation is a point or a line connecting
points that do not change position while that object rotates, drawn when
the observer assumes he/she does not change position relative to that
object over time.

Conventionally, the *direction* of the axis of rotation is such that if
you look in that direction, the rotation appears clockwise, as
illustrated below, where the yellow arrow shows the rotational movement,
while the purple one shows the rotation axis:

![](RotationAxisDirections.png "RotationAxisDirections.png")

To remember this convention, hold your right hand in a thumbs-up
gesture:

![](Right-hand_grip_rule.svg "Right-hand_grip_rule.svg"){width="100"}

If the rotation follows the direction of your curled fingers, then the
direction of the axis of rotation is considered to be the same as the
direction which the thumb is pointing in.

This gesture is a different form of the right-hand rule and is sometimes
called *the right-hand grip
rule*,
*the corkscrew-rule* or *the right-hand thumb rule*. From now on we will
refer to it as \'the right-hand grip rule\'.

When describing the direction of a rotating object, do not say that it
rotates *left-to-right/clockwise*, or *right-to-left/counterclockwise*.
Each of these on their own are meaningless, because they\'re relative to
the observer. Instead of saying this, find the direction of the axis of
rotation and draw an arrow to represent it. Those who know the
right-hand grip rule will be able to figure out what the direction of
rotation of the object is, by using the rule when interpreting your
drawing.

## Additional Resources

-   the *Geometry* wikibook

-
-
-
-


# Blender 3D: Noob to Pro/Orthographic Views

|previous=Coordinate Transformations
|subcat=Background
}}
```
\_\_TOC\_\_

## Orthographic Views

An  view (or projection)
of a 3D scene is a 2D picture of it in which parallel lines appear
parallel, and all edges perpendicular to the view direction appear in
proportion, at exactly the same scale.

Orthographic views are usually aligned with the scene\'s primary axes.
Edges parallel to the view axis disappear. Those parallel to the other
primary axes appear horizontal or vertical. The commonly used
orthographic views are front, side, and top views, though back and
bottom views are possible.

Uniform scale makes an orthographic view very useful when constructing
3D objects, not only in computer graphics, but also in manufacturing and
architecture.

Here\'s one way to think about the orthographic view:

Imagine photographing a small 3D object through a telescope from a very
great distance. There would be no foreshortening. All features would be
at the same scale, regardless of whether they were on the near side of
the object or its far side. Given two (or preferably three) such views,
along different axes, you could get an accurate idea of the shape of the
object, useful for \"getting the feel\" of objects in a virtual 3D world
where you\'re unable to touch or handle anything!

## Example

Here is a drawing of a staircase:

!An isometric view of a
staircase{width="300"}

and here are three orthographic views of the same staircase, each
outlined in red:

!**Figure 1:** \"First Angle\" Orthographic views of a
staircase{width="600"}

The views are from the front, top, and left. Dashed lines represent
edges that, in real life, would be hidden behind something, such as the
left wall of the staircase. (Think of each view as an X-ray image.)

The leading edges of the steps are visible in both the front and top
views. Note that they appear parallel and of equal length in 2D, just as
they are in 3D reality.

## Additional Resources

-


# Blender 3D: Noob to Pro/Perspective Views

|previous=Orthographic Views
|subcat=Background
}}
```
As you know, the main reason for modeling 3D objects in Blender is to
render images that exhibit the illusion of depth.

Orthographic views are great for building a house, but seriously flawed
when it comes to creating realistic images of the house for use in a
sales brochure. While a builder wants blueprints that are clear and
accurate, a seller wants imagery that\'s aesthetically pleasing, with
the illusion of depth. Blender makes it easy to use tricks like
perspective, surface hiding, shading, and animation to achieve this
illusion.

How does perspective work?

The essence of  is to
represent parallel edges (in a 3D scene) by edges (in the 2D image) that
*are not parallel*. When done correctly, this produces
 (nearby objects are
depicted larger than distant ones) and contributes to the illusion of
depth.

Perspective is challenging to draw by hand, but Blender does it for you,
provided you give it a 3D model of the scene and tell it where to view
the scene from.

If you\'re confident you understand perspective, you can skip the rest
of this module and proceed to
.

## One-point Perspective

!**Figure 1:** 1-Point
Perspective.{width="200"}

Drawing classes teach various kinds of perspective drawing: one-point
perspective, two-point perspective, and three-point perspective. In this
context, the word \"point\" refers to what artists call the *vanishing
point*.

When you\'re looking at a 3D object head-on and it\'s centered in your
view, that is an example of one-point perspective.

Imagine looking down a straight and level set of train tracks. The
tracks appear to converge at a point on the horizon. This is the
.

The image on the right is a 2D image of a cubic lattice or framework.
Like any cube, it has six square faces and twelve straight edges. In the
3D world, four of the edges are parallel to our line-of-sight. They
connect the four corners of the nearest square to the corresponding
corners of the farthest one. Each of these edges is parallel to the
other three.

In the 2D image, those same four edges appear to converge toward a
vanishing point, contributing to the illusion of depth. Since this is
one-point perspective, there is a single point of convergence at the
center of the image.

## Two-point Perspective

!**Figure 2:** 2-Point
Perspective.{width="200"}

Now the cube is at eye level, and you\'re near one of its edges. Since
you\'re not viewing it face-on, you can\'t draw it realistically using
one-point perspective. The horizontal edges on your left appear to
converge at a point on the horizon to the left of the cube, while those
on the right converge to the right. To illustrate the cube with a good
illusion of depth, you need two vanishing points.

## Three-point Perspective

!3-Point
Perspective.{width="200"}

Now imagine you\'re above the cube near one of its corners. To draw it,
you\'d need three vanishing points, one for each set of parallel edges.

From that perspective, there are no longer any edges which appear
parallel. The four vertical edges, the four left-right edges, and the
four in-out edges each converge toward a different vanishing point.

## Additional Resources

-


# Blender 3D: Noob to Pro/Coordinate Spaces in Blender

| previous=Perspective Views
| subcat=Background
}}
```
\_\_TOC\_\_ !**Figure 1:** Objects in a three dimensional space. In the
center of the coordinate system is the origin of the global coordinate
system.{width="400"}

We\'ll start looking at how 3D scenes are represented in Blender.

As was explained in ,
Blender represents locations in a scene by their coordinates. The
coordinates of a location consist of three numbers that define its
distance and direction from a fixed origin. More precisely:

-   The first (or x-) coordinate of the location is defined as its
    distance from the YZ plane (the one containing both the Y and Z
    axes). Locations on the +X side of this plane are assigned positive
    x-coordinates, and those on the -X side are given negative ones.
-   Its second (or y-) coordinate is its distance from the XZ plane,
    with locations on the -Y side of this plane having negative
    y-coordinates.
-   Its third (or z-) coordinate is its distance from the XY plane, with
    locations on the -Z side of this plane having negative
    z-coordinates.

Thus the origin (which lies at the junction of all three axes and all
three planes) has the coordinates (0, 0, 0).

## Global and local coordinates

Blender refers to the coordinate system described above as the
, though
it\'s not truly global as each scene has its own global coordinate
system. Each global coordinate system has a fixed origin and a fixed
orientation, but we can view it from different angles by moving a
virtual camera through the scene and/or rotating the camera.

Global coordinates are adequate for scenes containing a single fixed
object and scenes in which each object is merely a single point in the
scene. When dealing with objects that move around (or multiple objects
with sizes and shapes), it\'s helpful to define a **local coordinate
system** for each object, i.e. a coordinate system that can move with,
and follow the object. The origin of an object\'s local coordinate
system is often called the **center of the object** although it needn\'t
coincide with the geometrical center of the object.

3D objects in Blender are largely described using
 (points in the object,
singular form: **vertex**). The global coordinates of a vertex depend
on:

-   the (x, y, z) coordinates of the vertex in the object\'s **local**
    coordinate system
-   the location of the object\'s center
-   any rotation (turning) of the local coordinates system relative to
    the global coordinate system, and
-   any scaling (magnification or reduction) of the local coordinate
    system relative to the global coordinate system.

For example, the teacup in Figure 1 is described by a mesh model
containing 171 vertices, each having a different set of local (x, y, z)
coordinates relative to the cup\'s center. If you
 the cup (move it without
rotating it), the only bits of the model that have to change are the
global coordinates of the center. The local coordinates of all its
vertices would remain the same.

### Coordinates of child objects

!**Figure 1b:** A parent serves as the source of the global coordinates
for its child object. The child is the cup; the parent\'s orientation is
shown with the colored arrows. !Animation of the
above{width="200"}
{width="400"}

Any object can act as a  for
one or more other objects in the same scene, which are then referred to
as its . (An object cannot
have more than one direct parent, but parent objects may themselves be
the children of other objects.)

If an object has a parent, its position, rotation, and scaling are
measured in the parent\'s local coordinate system, almost as if it were
a vertex of the parent. i.e. the position of the child\'s center is
measured from the parent\'s center instead of the origin of the global
coordinate system. So if you move a parent object, its children move
too, even though the children\'s coordinates have not changed. The
orientation and scaling of a child\'s local coordinate system are
likewise measured relative to those of its parent. If you rotate the
parent, the child will rotate (and perhaps revolve) around the same
axis.

Parent-child relationships between objects make it simpler to perform
(and animate) rotations, scaling and moving in arbitrary directions. In
**Fig. 1b** the teacup is a child object of the coordinate cross on the
right. That cross is itself the child of an invisible parent. (It is
both a parent and child.) In the cup\'s local coordinate system, it is
not rotating, but as the cross on the right rotates around its Z axis,
it causes the cup to rotate and revolve. In real animations, it will be
much easier when the character holding the cup rotates, the cup changes
its position respectively.

## View coordinates

!**Figure 2:** View coordinates and Projection
Plane{width="400"}
Taking the viewer of the scene into consideration, there is another
coordinate space: the view coordinates. In **Fig. 2** the viewer is
symbolized by the camera. The Z axis of the view coordinates always
points directly to the viewer in orthographic projection. The X axis
points to the right, the Y axis points upwards (**Fig. 3**).

!**Figure 3:** View coordinates in viewing
direction{width="200"}
In fact you always work in view coordinates if you don\'t set it any
other way\*. This is particularly useful if you have aligned your view
prior to modeling something, e.g. if an object has a slanted roof and
you want to create a window to fit in that roof, it would be very
complicated to build the window aligned to the local coordinate system
of the object, but if you first align your view to the slanted roof, you
can easily work in that view coordinate system.

(\* In the Blender 2.6 series, the default has been changed to global
coordinates. View coordinates remain as an option.)

If you work in one of the three standard views (Front/Top/Side) the
alignment of the view coordinates fits the global coordinates.
Therefore, it is quite natural to model in one of the standard views and
many people find this the best way to model.

## Normal coordinates

!**Figure 4:** Normal coordinate spaces for faces. The normal is shown
in
blue.{width="400"}

Although Blender is a 3D program, only objects\' faces are visible. The
orientation of the faces is important for many reasons. For example, in
our daily lives it seems quite obvious that a book lies flat on a table.
This requires the surface of the table and that of the book to be
parallel to each other. If we put a book on a table in a 3D program,
there is no mechanism that forces these surfaces to be parallel. The
artist needs to ensure that.

The orientation of a face can be described with the help of the
so-called . It is
always perpendicular to the surface. If several faces are selected, the
resulting normal is averaged from the normals of every single face. In
**Fig. 4** the normal coordinates of the visible faces are drawn.

This concept can be applied to individual points on the object, even if
the points themselves have no orientation. The normal of a point is the
average of normals of the adjacent faces.

## UV Coordinates

In later parts (for example, talking about textures) you will come
across coordinates labelled "U" and "V". These are simply different
letters chosen to avoid confusion over "X", "Y" and "Z". For example, a
raster image is normally laid out on a flat, two-dimensional plane. Each
point on the image can be identified by X and Y coordinates. But Blender
can take this image and wrap it around the surface of a 3D object as a
texture. Points on/in the object have X, Y and Z coordinates. So to
avoid confusion, the points on the image are identified using U and V to
label their coordinates instead of X and Y. We then refer to "UV
mapping" as the process of determining where each (U, V) image point
ends up on the (X, Y, Z) object.


# Blender 3D: Noob to Pro/User Interface Overview

|previous=Coordinate Spaces in Blender
|subcat=Background
}}
```
Blender\'s **user interface** (the means by which you control the
software) is not particularly easy to learn. However, it has improved
over time and is expected to continue doing so. The current version of
the Blender software is available for download from the Blender
Foundation\'s website.

The tutorials in this section will familiarize you with the basics of
the user interface. By the end of this section, you should be able to:

-   resize, split, and merge any Blender window;
-   change the type of any Blender window;
-   access user preferences;
-   access panels containing buttons and other controls;
-   change the viewpoint of a viewport.

For those new to Blender, this is a fundamental section of the book.

### Advice on Customization

Blender is a complex software package with many customizable features.
You can customize the user interface to assign new functions to buttons
and hotkeys. In fact, you can change almost anything to suit yourself.
However, this complicates the giving and following of directions. It is
recommended you adhere to the default screen arrangements of Blender in
order to be able to follow the remaining parts of these tutorials.
Blender ships with 4 to 5 screen-content arrangements which are suitable
for almost any kind of job you\'ll want to use it for - from creating
motion and animation to making games.

We recommend leaving Blender\'s user interface in its \"factory
settings\" while working through the *Noob to Pro* tutorials. At the
very least, wait until you\'ve mastered the basics before you customize
the interface --- and we know you definitely will when you master it!


# Blender 3D: Noob to Pro/Keystroke, Button, and Menu Notation

|previous=User Interface Overview
|subcat=Background
}}
```
As you read through these tutorials, you will encounter cryptic codes
such as  and *Timeline → End
Frame*. They describe actions you perform using the keyboard and mouse.
The notation used in this book comes from the standard used by the
Blender community. We will try to import those standards here to
facilitate our studies.

If you\'re reading this book online, you may wish to print this page for
future reference. In addition, or as an alternative, you can bookmark it
in your browser for faster reference.

## Hotkeys

!A typical
numpad{width="100"} Most
computer keyboards have number keys in two different places. A row above
the letters, and in a  (numeric
keypad) to the right of the keyboard. While many applications use these
two sets of keys interchangeably, Blender does not. It assigns different
functions to each set. If you\'re using a laptop keyboard without a
separate numeric keypad, this might cause some difficulty. You\'ll need
to use your *function key* to do some things. It is possible to indicate
to Blender the type of keyboard you are using, but we strongly recommend
you use a standard external keyboard if you use a laptop for these
tutorials as it will make your studies and usage of Blender much more
straightforward and enjoyable.

This book often assumes your keyboard has a numpad. If yours doesn\'t,
consult the tutorial on Non-standard Input
Devices for
alternative ways to access the numpad\'s functions.

### Key Notation

```{=html}

```
+----------------------------------+----------------------------------+
| Notation                         | Corresponding key or action      |
+==================================+==================================+
| ```{=html}

```
When a key is used in a module, it means press that key. For exammple:

-       means \"press the **M** key\"

-       means \"press the **0** key thats found on the numpad.\"

Combinations that involve holding down a key while performing another
action are written with a plus sign (+). For example:

-       means \"press  while holding down
    \"

-       means \"press  while holding down
    both  and
    \"

```{=html}

```
```{=html}

```
### Mouse Notation

Blender uses three mouse buttons and the scroll wheel, if you have one.
If your mouse only has one or two buttons, consult the tutorial on
Non-standard Input
Devices for
alternative ways to access the functions assigned to these buttons.

```{=html}

```
+-----------------------+---------------------------------------------+
| Notation              | Corresponding action                        |
+=======================+=============================================+
| Mouse and keyboard actions are often combined.
 means to click
 while holding down
.

```{=html}

```
```{=html}

```
## Navigating Menus

Blender uses both pop-up and pull-down/pull-up menus. Many menus have
**sub menus** (menus that are reached via another menu). If a menu item
displays a triangle, that means it leads to a sub menu.

!The File
menu{width="100"}

You can move through items in a menu by either:

-   Moving the mouse pointer up and down

```{=html}

```
-   Pressing  and

You can enter a sub menu by either:

-   Moving the mouse pointer to the right

```{=html}

```
-   Pressing  while hovering
    over a menu item that shows a triangle on its side.

You can leave a sub menu by doing one of the following:

-   moving the mouse pointer to the left

```{=html}

```
-   pressing

To initiate a menu action, you can:

-   click

```{=html}

```
-   press

You can escape from a menu by:

-   moving the mouse pointer away from the menu

```{=html}

```
-   pressing

For each menu, Blender remembers your last choice and highlights it for
you the next time you enter the menu.

### Notation

Menu notation is fairly self-explanatory.

*Mesh → UV Sphere*

Means:

1.  Press Shift+A
2.  In the menu that pops up, move through the items until *Mesh* is
    highlighted
3.  Enter the *Mesh* sub menu
4.  Move through the items until *UV Sphere* is highlighted
5.  Press Enter or click the left mouse button to initiate the action

```{=html}

```
```{=html}

```
## Additional Resources

-
```{=html}

```