Interactive decal compositing with discrete exponential maps

Ryan Schmidt, Cindy Grimm, Brian Wyvill
2006 ACM SIGGRAPH 2006 Papers on - SIGGRAPH '06  
Figure 1 : A clay elephant statue (left) was modeled using sketch-based implicit-surface modeling software. Then, a lapped base texture and 25 feature textures were extracted from 22 images taken with a digital camera and composited on the surface. Photography, image creation, and texture positioning was completed in under an hour. Abstract A method is described for texturing surfaces using decals, images placed on the surface using local parameterizations. Decal parameterizations are generated
more » ... with a novel O(N log N ) discrete approximation to the exponential map which requires only a single additional step in Dijkstra's graph-distance algorithm. Decals are dynamically composited in an interface that addresses many limitations of previous work. Tools for image processing, deformation/feature-matching, and vector graphics are implemented using direct surface interaction. Exponential map decals can contain holes and can also be combined with conformal parameterization to reduce distortion. The exponential map approximation can be computed on any point set, including meshes and sampled implicit surfaces, and is relatively stable under resampling. The decals stick to the surface as it is interactively deformed, allowing the texture to be preserved even if the surface changes topology. These properties make exponential map decals a suitable approach for texturing animated implicit surfaces.
doi:10.1145/1179352.1141930 fatcat:2t3dspgatracxklxbzosdd43ju