Hand-painted Animation with Intelligent Brushes Tom Van Laerhoven, Fabian Di Fiore & Frank Van Reeth Hasselt University - Expertise Centre for Digital Media transnationale Universiteit Limburg Belgium CASA’08 CASA’08 Sep 1th - Sep 3thTom Van Laerhoven

Goals CASA’08 Sep 1th - Sep 3thTom Van Laerhoven Enrich interactively created stylized images with procedural animation. Make animation techniques available to untrained users. Avoid steep learning process.

Approach CASA’08 Sep 1th - Sep 3thTom Van Laerhoven Physically-inspired interactive painting tool “AquaVerve”. Animated canvas with separate canvas for each frame. Special-purpose “intelligent” brushes. Animated pigment. Show animation continuously.

Background CASA’08 Sep 1th - Sep 3thTom Van Laerhoven 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]

AquaVerve CASA’08 Sep 1th - Sep 3thTom Van Laerhoven Interactive paint system Watercolour, gouache, impasto, … Physically & empirically- based paint algorithms, GPU impl. [Van Laerhoven et al. CASA05] Virtual brush design [Van Laerhoven CGI07]

Animated Canvas CASA’08 Sep 1th - Sep 3thTom Van Laerhoven Set of 8 – 16 canvasses. Animation is shown continuously. Need for specialized brushes. canvas representation 1024x768 simulation grid

Intelligent Brushes CASA’08 Sep 1th - Sep 3thTom Van Laerhoven Semi-autonomous brush: flame brush User: Interactively paint stroke System: Record: brush reservoir stroke trajectory brush attributes

Intelligent Brushes CASA’08 Sep 1th - Sep 3thTom Van Laerhoven Semi-autonomous brush: flame brush … User: Interactively paint stroke Automatically-drawn scripted variations frame 0frame 1frame N System: Record: brush reservoir stroke trajectory brush attributes … undo

Intelligent Brushes CASA’08 Sep 1th - Sep 3thTom Van Laerhoven Semi-autonomous brush: flame brush … User: Interactively paint stroke Automatically-drawn scripted variations frame 0frame 1frame N System: Record: brush reservoir stroke trajectory brush attributes … undo

Intelligent Brushes CASA’08 Sep 1th - Sep 3thTom Van Laerhoven Moving-dab brush Paint dabs on successive frames

Intelligent Brushes CASA’08 Sep 1th - Sep 3thTom Van Laerhoven Steady brush Paint on all frames at once Erase animated strokes Painting motionless background Erasing animation

Animated Pigment CASA’08 Sep 1th - Sep 3thTom Van Laerhoven Secondary motion E.g., animate the observed thickness of a single pigment type in impasto paint layer Vibrant or waving paint textures Single-out a pigment type in a mix Pigment properties: stickiness clumping weight animation

Results CASA’08 Sep 1th - Sep 3thTom Van Laerhoven Camp fire Semi-autonomous flame brush Primary flames Smoke trail Moving-dab brush Secondary flames Steady brush Background Yellow pigment with vibrant flame-like motion

Results CASA’08 Sep 1th - Sep 3thTom Van Laerhoven Flowing water Semi-autonomous water brush Blue pigment that exhibits soft waving motion

Conclusions & Future Work CASA’08 Sep 1th - Sep 3thTom Van Laerhoven 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

Thank You Questions? CASA’08 Sep 1th - Sep 3thTom Van Laerhoven