3DCG Illustrations [Week 12]
Non-Research Tips for Information Science Researchers
情報科学研究補助技法

Yuki Koyama | httsp://koyama.xyz/ | https://non-research-tips.github.io/• 2017:

Ph.D. from UTokyo (Computer Science)• 2017—Current:

Researcher (Senior Researcher; 2022‒) at AIST (産業技術総合研究所)

httpYuki Koyama
⼩⼭ 裕⼰
https://koyama.xyz/• 2021—Current:

Technical Adviser at Graphinica, Inc. (an animeproduction company using 3DCG)• 2022—Current:

Part-Time Lecturer at UTokyo (Computer Graphics)2Motivation: Why 3DCG?

🤔

In general, good illustrations …
1. help audience better understand your research💡, and
2. increase presentation appeal 💖 (→ buzz).
3DCG is (sometimes) an effective technique for these purposes.

1. Better Understanding💡• Processed faster by thebrain, making it easier
for audiences to grasp
information• Provides visual

representations thatmake complex ideas anddata more accessible
https://www.youtube.com/watch?v=2LPboySOSvo

6

2. Presentation Appeal 💖

• Make presentations
more memorable,
leading to better
communication• Capture theaudience’s
attention

https://www.youtube.com/watch?v=VBZ2sDxvZQE7

Which is better?

Particle-based fluid simulation result, showing eachparticle as a black dot

The same result with fancy lighting and coloringWhich do you want to retweet?

Scenarios: When to Use 3DCG?

🤔

Illustrating Complex Concepts

Image from https://www.ruder.io/optimizing-gradient-descent/11

Illustrating
ComplexConcepts

Images from https://www.cs.cmu.edu/~kmcrane/Projects/Other/IllustratingGeometry.pdf

12Illustrating
Complex
ExperimentalSettings

Images from https://ieeexplore.ieee.org/document/10461983

13

Mechanical Assemblies: Step-by-Step Assemble

1:01—1:34

https://www.youtube.com/watch?v=Cd09lh2cXnc

14Mechanical
Assemblies:Exploded View
Animation• Help understanding of theassembly, and• Simply attractive
The 3D model was provided by George Kayesi for tutorial purposes
https://www.youtube.com/watch?v=IC0-9b0Rv2g
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Simulation Results

Simulation Results

Simulation Results

Simulation Results (even 2D!)

Simulation Results (even 2D!)

Motion Capture Data Visualization

3DCG Software💻Blender• Comprehensive 3DCG software• Free and open source (GPL)• Programmer-friendly (next slide)

Image from https://www.blender.org/23Blender is … Programmer-Friendly! 🤝• Easy to install using command line
(see the right)• Able to run on (display-less) computingservers (e.g., ABCI)• Everything can be manipulated andautomated via Python APIs24

Other Software (Not Free)• 3DCG animation and VFX• Game engine• Maya• Unreal Engine• 3ds Max

• Unity• Houdini
• …

• CAD
• Rhinoceros• AutoCAD• Solidworks• …

25

3DCG Tips for Researchers
How to Create Good Illustrations?

💪Lighting Tips | Detailed in the following slides• Use soft shadow (avoidhard shadow)• Use cyclorama (infinitycurve) background• Environmental light is easyand useful27

Do you remember? — Week5 [Figures] by Koya Narumi
18

Avoid a non-diﬀused light

Strong shadow → Bad

Camera: iPhone 12 mini

Non-diﬀused light → Bad

Donʼt use a strong, non-diﬀused light like a summer beach.

Do you remember? — Week5 [Figures] by Koya Narumi
19

Use a diﬀused light

Soft shadow → Good

Diﬀused light → Good

The diﬀused light like a cloudy sky is much better.

Lighting: Soft Shadow
Use a diﬀused lightPlane light• 3DCG can easily

create soft shadowsby using planelights• No need of

expensiveequipments as inreal-world
photography🥰

Soft shadow → Good

Diﬀused lightNo→ needGoodto buy this30

Lighting:
Cyclorama (InfinityCurve) Background• Curved background to create theillusion of an infinite space• Used in photography• Also useful in 3DCG

31

Lighting:
Environmental
Map• … is a texture that

represents thesurrounding
environment of a 3D
scene

• Highly useful for creating
realistic lighting (veryeasy🥹)32

Lighting: Where to Find HDR Images?

https://hdri-haven.com/

33

Lighting: File Format for Environmental Maps
• High Dynamic Range (HDR) image format (.hdr) is used
• Typical formats: unsigned int (8 bit/channel) — [0,255]• 😢 Cannot represent very bright (> 255) light sources (overexposure)• HDR format: float (32 bit/channel) — [0,∞)• 😃 Can represent more-than-1.0 values! 💪34

Materials Tips

• Reflection helps
better shapeperception💡

• But be careful ⚠️Reflection
increases visualclutter

with reflection

without reflection
35

Materials Tips• Reflection helps
better shapeperception💡

• But be careful ⚠️
Reflection
increases visualclutterwith reflection

without reflection
36

Camera Tips: Depth Blur
• Use depth blur for …
• Guiding viewers’ attention💡
• Creating emotional expressions 💖
• But avoid using depth blur in mosttechnical illustrations ⚠️37

Depth of Field (in real world)

https://jherr.github.io/depth-of-field/

Scripting Tips
• Everything that you can do with GUI can be done via Python API• Automation is easy
• Once scripting is done, it runs even on computing servers (e.g., ABCI)• It is easy to integrate Blender into your data processing pipeline• E.g., Checkpoint visualization during the training of 3D-related ML models(3D shape generation, point cloud segmentation, human motion
generation, etc.)• E.g., Visualization of fluid simulation results from various viewpoints(which is useful to check and validate the simulation behavior)

39

Demonstration

The 3D model was provided by George Kayesi for tutorial purposes
https://www.youtube.com/watch?v=IC0-9b0Rv2g

Environmental map
is used to create
fancy reflection

Exploded viewanimation(1) helps
understanding of
the assembly, and(2) is attractive

Slight rotation helps
shape perception
Cyclorama (infinitycurve) background

Soft shadow is often
preferredMastering 3DCG: Where to Start?

Resources
The "Donut" Tutorial
https://www.youtube.com/@blenderguru

43Resources• Exploded View Animation of Objects in Blender (Tutorial)• https://www.youtube.com/watch?v=IC0-9b0Rv2g• Illustrating Geometry (Keenan Crane)• https://www.cs.cmu.edu/~kmcrane/Projects/Other/IllustratingGeometry.pdf• Multi-scale Multi-physics Heart Simulator UT-Heart• https://www.youtube.com/watch?v=2LPboySOSvo• Blender Python scripting examples• https://github.com/yuki-koyama/blender-cli-rendering

44Summary🎉In general, good illustrations …
1. help audience better understand your research💡, and
2. increase presentation appeal 💖 (→ buzz 🧨).
3DCG is (sometimes) an effective technique for these purposes.