Hand-painted Animation with

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• Hand-painted Animation with
• Intelligent Brushes
• Tom Van Laerhoven, Fabian Di Fiore Frank Van
  Reeth
• firstname.lastname_at_uhasselt.be
• Hasselt University - Expertise Centre for Digital
  Media
• transnationale Universiteit Limburg
• Belgium
• CASA08

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Goals

• Enrich interactively created stylized images with
  procedural animation.
• Make animation techniques available to untrained
  users.
• Avoid steep learning process.

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Approach

• Physically-inspired interactive painting tool
  AquaVerve.
• Animated canvas with separate canvasfor each
  frame.
• Special-purpose intelligent brushes.
• Animated pigment.
• Show animation continuously.

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Background

• Commercial packages Corel Painter, MoXi,
  ArtRage, Project Dogwaffle
• Only provide digital equivalent of traditional
  painting.
• Literature

I/O Brush Ryokai et al. CHI04
Easel Rozin 98
Paint-Cam Rozin 98
AntBrush Tzafestas 00
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AquaVerve

• Interactive paint system
• Watercolour, gouache, impasto,
• Physically empirically-based paint algorithms,
  GPU impl.Van Laerhoven et al. CASA05
• Virtual brush design Van Laerhoven CGI07

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Animated Canvas

• Set of 8 16 canvasses.
• Animation is shown continuously.
• Need for specialized brushes.

canvas representation1024x768 simulation grid
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Intelligent Brushes

• Semi-autonomous brush flame brush

User Interactively paint stroke

• System
• Record
• brush reservoir
• stroke trajectory
• brush attributes

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Intelligent Brushes

• Semi-autonomous brush flame brush

frame 0
frame 1
frame N

undo
User Interactively paint stroke
Automatically-drawn scripted variations

• System
• Record
• brush reservoir
• stroke trajectory
• brush attributes

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Intelligent Brushes

• Semi-autonomous brush flame brush

frame 0
frame 1
frame N

undo
User Interactively paint stroke
Automatically-drawn scripted variations

• System
• Record
• brush reservoir
• stroke trajectory
• brush attributes

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Intelligent Brushes

• Moving-dab brush
• Paint dabs on successive frames

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Intelligent Brushes

• Steady brush
• Paint on all frames at once
• Erase animated strokes

Painting motionless background
Erasing animation
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Animated Pigment

• Secondary motion
• E.g., animate the observed thickness of a single
  pigment type in impasto paint layer
• Vibrant or waving paint textures

• Pigment properties
• stickiness
• clumping
• weight
• animation

Single-out a pigment type in a mix
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Results

• Camp fire
• Semi-autonomous flame brush
• Primary flames
• Smoke trail
• Moving-dab brush
• Secondary flames
• Steady brush
• Background
• Yellow pigment withvibrant flame-like motion

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Results

• Flowing water
• Semi-autonomous water brush
• Blue pigment that exhibits soft waving motion

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Conclusions Future Work

• Brushes pigment enhanced with behavioral
  intelligence
• Enrich animate interactively created images
• Within reach of every digital painter
• Future work
• Animation of stroke textures
• Extend intelligent brush set more complex
  scripts

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Thank You

• Questions?
• http//research.edm.uhasselt.be/tvanlaerhoven