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Explore advanced techniques in Non-photorealistic Rendering (NPR) to convey shape and artistic style through suggestive contours and line rendering. Learn to implement suggestive contour rendering for triangular meshes. Use provided code to display and interact with meshes. Dive into the paper "Suggestive Contours for Conveying Shape" by DeCarlo et al. for insights and guidance on implementing the rendering algorithm. Elevate your skills in computer graphics with this final programming assignment in advanced topics.
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Suggestive Contours Final programming assignment Advanced topics in Computer Graphics
Non-photorealistic rendering (NPR) • Rendering techniques aimed at • Conveying shape • sketching, rough idea of the shape • Conveying specific artistic style • hand-drawn • hatching • etc…
Line rendering to convey shape • How to make the computer draw the surface as a line rendering?
Line rendering to convey shape • Silhouettes (or contours) • edges on the surface where one side is turned to the viewer and the other away from the viewer) n v <v, n> = 0
Line rendering to convey shape • Silhouettes (or contours) • are probably not enough… only contours with suggestive contours only contours with suggestive contours
Line rendering to convey shape • Suggestive contours: • extension of regular silhouettes • points on the surface that will turn into silhouettes in near-by views
Suggestive contours • Formal definition: inflection points of radial curvature
Suggestive contours • Formal definition: inflection points of radial curves (i.e. zeros of radial curvature)
Suggestive contours • Computation • Object space: • compute radial curvatures given the view (the eye) • find points of zero radial curvature, so that the radial curve changes from convex to concave • Image space: • put a diffuse light source at the eye • render and look for valleys (local minima of <n, v>) • this will give an approximation of pixels where radial curvature is zero
The assignment • To read the paper “Suggestive contours for conveying shape” by DeCarlo et al. • To implement suggestive contour (+ normal silhouette) rendering for triangular meshes, as described in the paper http://www.cs.tau.ac.il/~sorkine/courses/adv_cg/sc/
You get from us • A basic code to read meshes from known formats and to display them interactively • You should implement the rendering algorithm yourself