Draw Guide

3

Chapter
Working with Objects andObject Points

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separately.)CopyrightThis document is Copyright © 2005–2010 by its contributors as listed
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under the terms of either the GNU General Public License, version 3 orlater, or the Creative Commons Attribution License, version 3.0 or
later.
All trademarks within this guide belong to their legitimate owners.

Authors
Agnes Belzunce
Martin Fox
Gary Schnabl
Jean Hollis Weber
Linda Worthington

Daniel Carrera
Hazel Russmann
Wolfgang Uhlig
Claire Wood

Feedback
Please direct any comments or suggestions about this document to:authors@documentation.openoffice.org

Acknowledgments
This chapter is based on an original French document written for
OpenOffice.org 1.x by Michel Pinquier (translated to English by Alex
Thurgood) and previous content revised by Jim Taylor. The chapter
was revised for OpenOffice 2 by Linda, Daniel, Jean, and Agnes, andlater translated into German by Wolfgang Uhlig. The German revisions
were then translated into English and updated for OpenOffice 3.2 byMartin Fox. The original title of this chapter was “Editing Objects
Part 1 – Working with Objects and Points”.

Publication date and software version
Published 28 July 2010. Based on OpenOffice.org 3.2.

You can download
an editable version of this document fromhttp://oooauthors.org/english/userguide3/published/

Contents
Copyright.................................................................................................2
Introduction.............................................................................................1
Selection modes....................................................................................1
Changing the selection mode...............................................................2
Selecting objects...................................................................................2
Direct selection..................................................................................2
Selection by framing.........................................................................3
Selecting hidden objects.......................................................................3
Arranging objects..............................................................................4
Moving and dynamically adjusting an object’s size................................4
Dynamic movement of objects..............................................................5
Dynamic size modification of objects...................................................5
Dynamic size modification of objects with the help of the status bar. 5
Modifying an arc...................................................................................6
Rotating and shearing an object using the mouse..................................7
Rotating................................................................................................7
Changing inclination or perspective....................................................8
Setting size and position exactly.............................................................9
Position and Size...................................................................................9
Rotating objects..................................................................................10
Slant and corner radius......................................................................10
Editing object points..............................................................................11
An alternative way to change the form of basic shapes........................12
How curves work...................................................................................13
The Edit Points toolbar.......................................................................13
The three kinds of tangent.................................................................14
Examples.............................................................................................15

Working with Objects and Object Points

3

Introduction
This chapter looks at the tools and functions that let you modify
existing drawings. All of the functions apply to a selected object orgroup of objects, which can be distinguished by small colored squares
or circles located around it. These points are called handles.
The handles form a rectangular frame that is just big enough tocontain the object. Where several objects are selected, the frame
around them corresponds to the smallest rectangle that can contain allof the objects. This frame is called the selection rectangle.
If the Options bar is displayed (select View > Toolbars > Options toturn it on, if it is not displayed), you can change the size of the handles
using two buttons: Simple Handles shows the handles as flat squares;
otherwise they are shown in 3D. Large Handles increases the size ofthe handles. You can combine the two effects. The figure below shows
the location of the handles and other buttons.

Figure 1: Location of handles on the Options toolbar

Selection modes
There are three selection modes:
1) Moving and changing size2) Editing
3) Rotating points
To set the default mode (1 or 2) for selecting objects, click on the
Points buttonon the Drawing toolbar.
In standard mode (when you begin a new drawing),
the Points button is not active, and the default modeis for selections to be moved or changed in size;these selections are indicated by small green
squares.

Introduction

1

When the Points button is active, the default mode isfor selections to be edited; these selections areindicated by blue squares. Some objects will have one
or more extra handles, which are larger or coloreddifferently. This is explained in more detail in“Editing object points” on page 11.
Selections for rotating objects are indicated by small
red circles and a symbol representing the center ofrotation. To choose these selections, click on the
Effects drop-down button
from the Drawing
toolbar and after that on the object.

Changing the selection mode
To go from one mode to another, you can do one of the following:• Choose the Points button

from the Drawing toolbar to switchfrom simple selection mode to Points mode. You can also use the
keyboard shortcut F8 (Points). See “Editing object points” onpage 11 for details on using Points mode.
• Choose the Effects drop-down button from the Drawing Toolbar
to activate the Rotation mode for a selected object. To exit
Rotation mode, click on the Selection icon.
• If you often work in Rotation mode, you can choose the Rotation
Mode after Clicking Object button
from the Options bar
and cycle through normal and rotation modes just by clicking on
the object. This can be more convenient than repeatedly clicking
the selected object, then clicking the Rotate button from theDrawing toolbar.

Selecting objects
Direct selection
The easiest way to select an object is to click directly on it. For objects
that are not filled, click on the object’s outline to select it. One click
selects; a second click deselects. To select or deselect more than one
object, hold the shift button down while clicking.

2

Working with Objects and Object Points

Selection by framing
You can also select several objects at once by using themouse to drag a large rectangle around the objects
with the Select button, as shown. For this to work, theicon on the Drawing toolbar must be active.
Only objects that lie entirely within the rectangle will
be selected.

Selecting hidden objects
Even if objects are located behind others and not visible, they can still
be selected. Hold down the Alt key and click where the object islocated. If there are several overlapping objects, hold down the Alt key
and click until you reach the object you want. To cycle through theobjects in reverse order, hold down the Alt+Shift keys and click. The
number and type of the selected objects is shown at the left of thestatus bar to help you to select the correct object.

NoteThis method generally works in Windows, but on a Linux system
it usually does not. If the Alt key on your system does notoperate as described above, use the Tab key method described
below.

To select an object that is covered by another object using the
keyboard, use the Tab key to cycle through the objects, stopping at theobject you wish to select. To cycle through the objects in reverse order,press Shift+Tab. This is a very quick way to reach the object you want,
but it may not be practical if you have a large number of objects inyour drawing.
When you click on the selected object, its outline will appear briefly
through the objects covering it.
In the illustration to the right, the square locatedbeneath the circle was selected in this way (thecircle has been made semi-transparent in order toshow the square).

Introduction

3

Arranging objects
In a complex drawing, several objects may be stacked on top of one
another. To rearrange the stacking order (move an object to the front
or to the back of the stack), select the object, click Modify > Arrange
and choose Bring Forward or Send Backward. Or right-click theobject, choose Arrange from the context menu, then choose Bring
Forward or Send Backward.
These options are also available from the Arrange tear-off toolbar
accessible from theicon on the Drawing toolbar. A keyboard
shortcut is Shift+Ctrl+plus sign to bring an object to the top, andShift+Ctrl+minus sign to send an object to the bottom.
Note, however, that an object located on the Controls layer always lies
above all other objects.

Moving and dynamically adjusting an
object’s size
There are several ways of moving or changing the size of an object.
The dynamic method described here uses the mouse.
When you dynamically change an object, remember to check the lefthand area of the status bar at the bottom of the Draw window. This
area shows detailed information about the ongoing manipulation

Figure 2: Left end of status bar during dynamic adjustment
For example, when you are resizing an object, the object information
fields show which object is selected, the current position in X/Ycoordinates, and object dimensions (width x height). The information
4

Working with Objects and Object Points

changes as the mouse is moved. The units of measurement are those
selected under Tools > Options > OpenOffice.org Draw > General.

Dynamic movement of objects
To move an object, select it and then click within theobject’s border and hold down the left mouse button
while dragging the mouse. During movement, theshape of the object appears as dotted lines to help
with repositioning.
To drop the object at its new location, release the mouse button. The
new position appears immediately in the Status Bar.

Dynamic size modification of objects
To change the size of a selected object (or a group of
selected objects) with the mouse, move one of thehandles located around the selection. As shown in theillustration, the outline of the resulting new object
appears as a dotted line while the mouse button ispressed.
The results depend on which handle you use. To resize an object along
one axis, use the appropriate side handle. To resize along both axes,
use a corner handle. The new size appears immediately in the status
bar.
Note

If you press the Shift key while resizing an object, the change insize will be carried out symmetrically with respect to the twoaxes, so that the aspect ratio of the object remains the same.

Dynamic size modification of objects with the helpof the status bar
If you select an object and modify it using the mouse, the changes are
immediately reflected in the information field of the status bar. With
geometric shapes (such as basic shapes, symbol shapes, block arrows),
the only information shown in the status bar is that the shape is being
resized, as shown in the top-left image in Figure 3. With geometricelements (rectangles, circles, and so on), the changes to the attributesof the element (either relative or absolute) are also shown, as in the
top-right image in Figure 3.
Moving and dynamically adjusting an object’s size

5

Figure 3: The Information field during dynamic size
modification of objects
In the case of a rectangle, the new size is shown as percentages of theoriginal x and y dimensions. For a line, much more information is
given: the absolute change in x and y coordinates of the end point
being moved, together with the current length and bearing of themodified line. These are updated dynamically as the end point is moved(see Figure 3).
This is the only place where the exact start and end angles of an arc or
the length and bearing of a sloping line are shown. This information
enables you to size the object with considerable accuracy.

Modifying an arc
The beginning and end points of an arc can be modified. Select the arc
and click on the Points iconon the Drawing toolbar to enter the
Edit points mode (described later in this chapter). In this mode, thehandles on the selection frame change—two larger blue handles
appear at the beginning and end points of the arc. When the mouse
hovers over one of these points the cursor will change to a hand.

Figure 4: Editing an arc

6

Working with Objects and Object Points

If you click and hold the mouse button when the hand cursor appears,
moving the mouse will change the location of the start or end point of
the arc. The actual coordinates are shown in the Status Bar (see lower
left graphic in Figure 3.

Rotating and shearing an object using themouse
Use the red rotation handles to either rotate an object around an axis
or slant or shear the object.

Rotating
To rotate an object (or a group of objects), drag a red corner handle
point of the selection with the mouse. The mouse cursor takes theshape of an arc of a circle with an arrow at each end. A dotted outlineof the object being rotated appears and the current angle of rotation is
dynamically shown in the status bar.

Note

Rotation works in a slightly different way for 3D objects because
the rotation occurs in 3D space and not in one plane. See
Chapter 7 (Working with 3D Objects) regarding rotation when
the Edit Points mode is active.

Rotations are made about an axis which is displayed as a small symbol.
This is normally located at the midpoint of the object, but you canmove the axis of rotation with the mouse to any location you like, evenoutside the object.
If you hold down the Shift key during the rotation, the operation will be
carried out in increments of 15°.

Figure 5: Rotating an object

Rotating and shearing an object using the mouse7Changing inclination or perspective
To slant or shear objects, use the red handles located at the midpointof an edge of the selected objects. The mouse pointer changes to awhen the pointer hovers over one of these midpoint handles. Not every
object can be slanted—basic shapes can be rotated but not slanted.
The slant axis is the point directly opposite the midpoint handle to be
used for shearing the object. This point stays fixed in location; theother sides and edges move in relation to it as the mouse is dragged(make sure that theicon is showing before dragging).
Figure 6 shows how the vertices move in relation to each other during
the shearing process. The circles represent the path of the vertices.
The inclination axis is the bottom vertex of the triangle (the slanting
handle used is the midpoint of the upper enclosing frame). All points
on the figure will move through the same angle irrespective of the final
shape. The actual angle is shown in the status bar.

Figure 6: Shearing an object
Note

The triangle in Figure 6 was produced with the (unfilled) polygon
tool and then Close Object was selected from the context menu.

This tool can be used to produce perspective drawings. The series ofpictures in Figure 7 shows the method of constructing a cuboid orrectangular prism. To shorten the edges leading from front to back,reduce the length before you distort the height or width of the surface.

Figure 7: Perspective production of a cuboid

8

Working with Objects and Object Points

As with rotation, you can make the slanting occur in steps of 15° bypressing the Shift key while moving the handle.

Setting size and position exactly
You can position and resize objects with the mouse, but this method is
not very exact. If you need accurate positioning of objects, use Format> Position and Size from the menu bar, or right-click the object andselect Position and Size from the context menu, or press F4.

Position and Size
Open the Position and Size dialog (see Figure 8) and click on the firsttab to set the appropriate values.

Figure 8: Position and size of an object
Position is defined as an X,Y coordinate relative to a fixed point (thebase point), typically located at the upper left of the drawing area. If
desired, you can temporarily change this base point to makepositioning or dimensioning simpler (click on the radio button
corresponding to the location of the base point in either of the two
selection windows on the right side of the dialog—upper for positioning
or lower for dimensioning). The possible base point positions
correspond to the handles on the selection frame plus a central point.
The change in position lasts only as long as you have the dialog open;
when you close this dialog, Draw resets the base point to the standard
position.
Setting size and position exactly

9

Tip

The Keep ratio checkbox is very useful. Click it to keep the ratioof width to height fixed while you change the size of an object.

Either or both the size and position can be protected so that theycannot be inadvertently changed. Check the appropriate boxes toachieve this.
Tip

You cannot move an object? Check to see if the position isprotected!

Rotating objects
Click on the Rotation tab of the Position and Size dialog (see Figure7). Here you can define the rotation angle, as well as the location of
the pivot point.

Figure 9: Rotating an object

Slant and corner radiusWith some Draw objects the slant angle (inclination or shearing) andcorner radius can be set in this dialog (Figure 10).

10Working with Objects and Object Points

Figure 10: Setting rounded corners and slant angle
Corner radiusFigure 11: Example of setting rounded corners
You can use this dialog to round the corners of the usual Draw objects—text boxes, legends, rectangles, and squares, as shown in Figure 11.
The same effect can be achieved when you are in the points mode (byclicking the Points icon on the Drawing toolbar), by dragging the large
handle with the mouse. The larger the value for the corner radius, themore round will be the object.
Slant
You can shear the older, classic Draw objects, but not the newer Shapeobjects. Enter the slant angle in the box marked Slant Angle.

Figure 12: Example of setting the slant angle in a classic Draw object

Editing object points
For polygons and Bézier curves, Draw offers a complete set of toolsthat let you accurately edit the contour of an object. To edit otherobjects in the same way, you must first convert them into curves. To dothis, select the object, then right-click and choose Convert > To
Curve or choose Modify > Convert > To Curve from the menu bar.
Editing object points

11You can also convert the shapes to a polygon (Convert > To
Polygon). With polygons, the edge points are always connected withstraight lines and not with curves. Some of the techniques described
work equally with polygons as with curves.

An alternative way to change the form ofbasic shapes
In current versions of Draw, many of the new shapes can be directlyedited without having to convert them to curves first. You canrecognize these objects by the presence of one (or more) circularyellow handles as shown in Figure 13. The mouse pointer changes
shape when hovered over a yellow handle.
If you drag one of these handles, you can modify the shape of theobject; the type of change is dependent on the shape itself. For
example, you can round the corners of a rectangle or square, change
the angles of an arc or ellipse, or alter the control points of a circularor elliptical segment.

Figure 13: Some basic shapes with yellow “handles”

12

Working with Objects and Object Points

How curves work
The editing of curves depends on the mathematics of Bézier curves1.
The complete study of such curves goes beyond this scope of thisguide, and only the basics are covered here. Chapter 10 (Advanced
Draw Techniques) provides more information on drawing andmanipulating Bézier curves.
The editing of a Bézier curve consists in principle of moving points ortangents passing through these points. Each tangent has two control
points—one at each end—and a junction point where it meets thecurve. The relative angle and distance between the control points
determine the shape of the curve. Figure 14 shows several variations
starting from a basic circle and changing only one point on the circle.
You can create many different shapes by moving either the junction
point itself, or one or both of the round handle points at either end of
the tangent.

Figure 14: Creating different shapes bychanging the tangent
Draw offers even more possibilities when you use the functions on the
Bézier curve toolbar.

The Edit Points toolbar
When you work in Edit Points mode, use the Edit Points toolbar, shownin Figure 15. To activate this toolbar, choose View > Toolbars > Edit
Points. It will then appear whenever you select a curve and the Edit
Points icon on the Drawing toolbar is active.

1 Bézier curves were invented by Pierre Bézier, an engineer working with the Renault car
manufacturer, who developed the technique in the 1960s. The technology was intended to makemodeling the surface of vehicles easier.

How curves work

13

1 Points
2 Move Points
3 Insert Points
4 Delete Points

5 Split Curve
6 Convert to Curve
7 Corner Point
8 Smooth Transition

9 Symmetric Transition
10 Close Bézier
11 Eliminate Points

Figure 15: Edit Points toolbar
On this toolbar, icons may be active or inactive depending on theselected object and object point. With the Convert to Curve icon, you
can determine for individual points whether their connection will bemade with straight lines or with curves.
Only with curves are the icons for tangents activated. An object that
contains no curves is treated as a polygon.

The three kinds of tangent
Three buttons in the Edit Points Toolbar let you select the type oftangent and convert from one type to another. Only one of thesebuttons can be active at any given time. Their use is described in thefollowing chapter.

Figure 16:
Symmetric
tangent

Figure 17:
Asymmetrictangent

14

Choose the Symmetric Transition button
to work with a symmetrical tangent (Figure 16).
Any movement of one or the other of thehandles is carried over symmetrically to theother handle.
Choose the Smooth Transition button
toseparately adjust the lengths of the two parts ofa tangent and so make the curve flatter orsteeper. In Figure 17, you can clearly see thatthe curve is flatter on the longest side of thetangent. The tangent remains as a single
straight line. This kind of tangent is known as asmooth junction.

Working with Objects and Object Points

Figure 18:
Inflexion
point

It is also possible to completely detach bothsides of the tangent. In this case, the central
point is known as the inflexion point. Using thistechnique, you can draw spikes and troughs in
objects. Choose the Corner Point button
to create an inflexion point around the selected
point.

ExamplesThe other buttons in the Edit Points Toolbar are described here in
relation to working examples. The following examples start from afilled circle. As mentioned earlier, in order to use Edit Points mode,you first need to convert the object to a curve.
You will notice that after the conversion, the handles located in thecorners of the rectangle have disappeared. This behavior is normal inthat the handles which are used in the Edit Points mode are locatedalong the outline or trace of the drawn object.

The Move Points button
is the default
mode when editing points. If it has not been
activated, click on its button. When this mode isactive, the mouse pointer has the following
shape when it is hovered over an edit point:

Figure 19: Moving
a junction point

How curves work

Movement of a point is one of the easiest
manipulations to do. Figure 19 illustrates how
you can draw an egg very easily by startingfrom a circle and dragging the the top point
upwards.

15

To change the direction or location of thetangents, move the circular handles at eachend. The mouse pointer then looks like this:Figure 20:
Rotating a tangent
Use the Add Points button
to add an extra
edit point to an existing curve. Click on the
curve at the spot where you want to insert apoint and then move the mouse slightly in any
direction while holding down the button. Watch
out! If you just click, the new point will not be
added.
Figure 21: Adding
an edit point to a
curve

The tangent attributes associated with the new
point depend on the buttons that are selected on
the toolbar.

➊

The Delete Points button
has the opposite
effect: it subtracts one or more points from thecurve. The resulting curve stretches itself
automatically around the remaining points after
subtraction.
Select one or more points to delete. You canselect several points by holding down the Shift
key (➊).
When you have selected the points you want to➋Figure 22: Deleting
points from a curvedelete, click the Delete Points
button. The
selected points disappear from the curve, whichthen reforms around the remaining points (➋).
You can also delete the selected points bypressing the Del key on the keyboard.

16

Working with Objects and Object Points

➊

➋

3

Use the Split Curve button
to split or cut acurve at the location of the selected handle. If
the object is filled, it will be emptied because
the curve that represented the edge is no longer
closed.
Check that you have selected the correct handle(➊), click the Split Curve button(➋) andnotice that the object is no longer filled. You canthen check, by moving the point, that the curve
has indeed been separated (➌).

Figure 23: Cutting a If you have an open curve, the start point of thecurve is larger than the others.
curve
You can also separate a curve at several points
simultaneously. Keep the Shift key pressed
down and select all of the points at which the
cut should occur.
Drag and drop segments with the mouse to
move them from the original curve.
Figure 24:
Moving asegment
To close an existing curve, select an open curveand click on the Close Bézier button.

The opening point is identified by a slightly
larger handle (Figure 25).

Figure 25:
Closing an open
curve
How curves work

17

➊

➋

The Select buttonon the Drawing toolbar
functions as a switch. It works as follows.
If you have two points linked together by astraight line (you do not need to have a curve
between the points) and you insert a new point
between them that is set at an angle to theinitial straight line (and hence the two
endpoints), then:• If the Select button is active, you will havea drawing similar to that illustrated in ➊.
Figure 26: Using
the “select points”
switch• If the Select button is not active, and you

move the point you have just inserted tobring it back close to its initial position in
the straight line, you will have a drawing
similar to that illustrated in ➋.
The Eliminate Points button
button only
functions with lines with multiple points.

1.
Select object and set If the button is active, click on a point, hold themouse button down and move the mouse to
Edit points mode
draw virtual straight lines between theneighboring left and right points.

2.
Draw virtual lines

3.
Release mousebuttonWhen the two lines are more or less straightand you release the mouse button, the point isdeleted and a line between the above mentioned
two neighboring points replaces the previous
two lines, thus eliminating one point.
Note that this only works when the angle
between the two lines shown dashed in the
figure at left is less than a certain amount.
In the Tools > Options > OpenOffice.org
Draw > Grid window there are options for snap
settings relating to editing points when rotating
and in point reduction mode.

Figure 27: Reducing
a line by one point

18

Working with Objects and Object Points

The Rotate function from the Effects drop-➊

down buttonon the Drawing toolbar andthe Rotation Mode after Clicking Object
buttonon the Options toolbar can be usedin Edit Point mode. In this case, it can be used
to move single points around the contour of an
object.
Switch into rotation mode by clicking on eitherof the rotation buttons. Notice that in rotationmode, all of the tangent points become red dots.

➋

Figure 28: Moving
a point on a curve

Select the point to be moved and then drag itaround the contour while keeping the left mousebutton pressed down (➊). When you release themouse button, the point will be moved to thenew position (➋).
If you move one of the handles located at theend of the tangents during rotation, you will
make the object rotate in exactly the same way
as with the usual rotation operations.
Important: To exit the effects mode, do not justclick on the Effects button; click the Selectbuttonon the Drawing toolbar.

How curves work19