1. View-Dependent Textured Splatting for Rendering Live Scenes
R. Yang, D. Guinnip and S. Lai

2. Goal
A novel approach to render low resolution point clouds with multiple high resolution textures---the type of data typically from real-time vision systems.

3. A Typical Way: Triangulation
robust 3D triangulation is a challenging computational problem, which means real-time triangulation is not yet feasible.
It can have the side effect of magnifying outliers.

4. Rendering Results from a Live Scene
Triangluar Mesh Rendering
Point Splatting Rendering
VDTS Rendering

5. Related Work Qsplat [in Siggraph 2000] Surfel [in Siggraph 2001]
VDTM [in Siggraph 1996]
Real-time VDTM using projective textures
[in 9th Eurographics 1998]
Unstructured lumingraph rendering
[in Siggraph 2001]

6. Two directions in Splat
Speed: rendering in real time by using multiresoltuion and LOD control techniques.
Quality : Carefully balancing points sampling density or precisely texture mapping

7. Visibility Issues
Projecting a three dimensional object to a two dimensional image plane, in most cases cause surface elements to overlap. Such overlapping can cause visual artifacts when occlusions and disocclusions are present.

8. Anti-Aliasing
Unlike most splating algorithm, VDTS uses splats that are usually much bigger than one screen pixel. As a result, anti-aliasing for high resolution textures can be handled directly by the graphics hardware.

9. Texture anti-aliasing
Each splat has only one color
Each splat is rendered with projective texture-mapping

10. Visibility processing
The visibility problem is equivalent to the shadow determination problem.
Fully supported by graphics hardware

11. Visibility Clipping
The visibility processing can be problematic at surface boundary.
In the presence of high resolution depth map, we can compare the fragment depth with the actual depth. If the difference is too large, then we know it is likely a part of extruding splat that should really be transparent.
The large circle represents one view, P and Q are splats leading to inaccuracy in silhouettes.

12. Results of Visibility Clipping
Bunny data set rendered with visibility clipping disabled/enabled