1. Interactive Rendering To View-Dependent Texture-Atlases Matthias Trapp & Jürgen DöllnerHasso-Plattner-Institut, University of Potsdam, Germany

2. Introduction & Problem Statement image-based representation of 3d shapes: Saito & Takahashi, 1990 derived using render-to-texture (RTT) (scene = texture) vs. (object = texture) numerous applications: post-processing effects, image-based occlusion management, client-server applications problems for (object = texture) : multiple objects results in multiple textures underutilized texturesfor objects not covering complete viewport 2 Trapp & Döllner :: Interactive Rendering to View-Dependent Texture Atlases

4. reduced memory footprint and texture management

5. applicable in a single rendering pass for static meshes

7. Conceptual Overview 5 Trapp & Döllner :: Interactive Rendering to View-Dependent Texture Atlases

8. Parameterization & Packaging 6 Trapp & Döllner :: Interactive Rendering to View-Dependent Texture Atlases 1+2 3+4 screen space texture space sorted bounding boxes re-compute atlas layout per-frameon CPU project3D boundary representations clipprojected coordinates and sort rectangles perform rectangular packing on CPU [Igarashi, 2001] compute transformation for screen-space vertex displacement

9. Screen Space Vertex Displacement concept introduced by Camera Textures [Spindler et al. 2006] applied per-primitive using geometry shaders fetch transformation using object ID from: original screen space position to: texture atlas position Trapp & Döllner :: Interactive Rendering to View-Dependent Texture Atlases 7

10. Render-To-Texture Atlas 8 Trapp & Döllner :: Interactive Rendering to View-Dependent Texture Atlases

11. Results & Discussion small number of objects: RTT is faster, but low TA utilization lower setup cost for high number of objects TA resolution should be multiples of screen resolutions implementation is not transform-bound 9 Trapp & Döllner :: Interactive Rendering to View-Dependent Texture Atlases

12. Wrap-Up & Conclusions concept of view-dependent texture atlases optimization for render-to-texture applications single-pass creation using: layered rendering screen-space vertex displacement trade-offs: #of objects vs. frames-per-seconds TA utilization vs. bounding approximation future work: evaluate different shape approximation GPU based TA packaging strategies 10 Trapp & Döllner :: Interactive Rendering to View-Dependent Texture Atlases

13. Thank you for your attention… contact: Matthias Trappmatthias.trapp@hpi.uni-potsdam.de JürgenDöllner juergen.doellner@hpi.uni-potsdam.de Computer Graphics Systems GroupProf. Dr. JürgenDöllnerwww.hpi.uni-potsdam.de/3d Researchgroup 3D-Geoinformationwww.3dgi.de 11 Trapp & Döllner :: Interactive Rendering to View-Dependent Texture Atlases