non-photorealistic rendering greg turk college of computing and gvu center
TRANSCRIPT
![Page 1: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/1.jpg)
Non-PhotorealisticRendering
Greg TurkCollege of Computing and GVU Center
![Page 2: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/2.jpg)
Painterly Rendering for Animation Barbara Meier, SIGGRAPH 1996
![Page 3: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/3.jpg)
Painterly Rendering Issues
• Frame-to-frame coherence (maintain strokes across time)
• Idea: fix brush strokes in screen-space
• Problem: shower door effect
• Better idea: fix brush strokes to object
![Page 4: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/4.jpg)
Painting Pipeline
Brushes (color & opacity):
![Page 5: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/5.jpg)
Different Brushes and Orientation Fields
![Page 6: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/6.jpg)
Draw Image in Layers
![Page 7: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/7.jpg)
Video
![Page 8: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/8.jpg)
Pen and Ink SketchesMike Salisbury, Michael Wong, John Hughesand David Salesin, SIGGRAPH 1997
![Page 9: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/9.jpg)
Pen and Ink
• Given: grayscale image (e.g. photo)
• Make: pen-and-ink illustration
• Approach:
Gray scaleimage
Directionfield
BrushStrokes
FinalImage+ + =
![Page 10: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/10.jpg)
Pen and Ink Sketches
ToneMap
OrientationField
Strokes
![Page 11: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/11.jpg)
Pen and Ink Sketches
ToneMap
OrientationField
Strokes
![Page 12: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/12.jpg)
Stroke Details
• Strokes are B-spline curves (similar to Bezier)
• Strokes clipped to silhouettes
• Stroke density controlled by blurred stroke image
• Strokes follow orientation field
![Page 13: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/13.jpg)
Painting Orientation Field
![Page 14: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/14.jpg)
Stroke Density
Strokes
BlurredStrokes
![Page 15: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/15.jpg)
![Page 16: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/16.jpg)
Stroke Density Varies with Drawing Size
![Page 17: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/17.jpg)
![Page 18: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/18.jpg)
Art-Based RenderingOf Fur, Grass andTrees
Kowalski, Markosian,Northrup, Bourdev,Barzel and Hughes,SIGGRAPH 2000
![Page 19: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/19.jpg)
Approach
• Real-time rendering
• Use reference images for color and object ID
• Place “strokes” based on density
• Try to place same strokes on next frame
![Page 20: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/20.jpg)
Reference Images: Hardware Rendering
![Page 21: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/21.jpg)
Final Image
![Page 22: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/22.jpg)
Stroke Drawing
![Page 23: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/23.jpg)
![Page 24: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/24.jpg)
![Page 25: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/25.jpg)
“Illustrating Smooth Surfaces”Aaron Hertzmanand Denis ZorinSIGGRAPH 2000
![Page 26: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/26.jpg)
Goals
• Create pen-and-ink strokes based on 3D geometry
• Show silhouettes
• Have cross-hatching
![Page 27: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/27.jpg)
Issues
• Silhouette detection
• Orientation field (use curvature)
• Hatching
• Undercuts
![Page 28: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/28.jpg)
Silhouette Detection
![Page 29: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/29.jpg)
Orientation Field Smoothing
![Page 30: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/30.jpg)
Orientation Field and Shading
![Page 31: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/31.jpg)
Hatching
![Page 32: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/32.jpg)
Hatching and Undercuts
![Page 33: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/33.jpg)
Results
![Page 34: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/34.jpg)
Results
![Page 35: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/35.jpg)
Other NPR
• Cel Animation
• Painterly Video
• Cel Video
• ???
![Page 36: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/36.jpg)
Painterly Video
“What Dreams May Come”
![Page 37: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/37.jpg)
Cel Animation: Zelda Windwalker
![Page 38: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/38.jpg)
Cel-Like Video
![Page 39: Non-Photorealistic Rendering Greg Turk College of Computing and GVU Center](https://reader036.vdocument.in/reader036/viewer/2022062322/56649d9c5503460f94a84623/html5/thumbnails/39.jpg)
End