Shading Languages By Markus Kummerer

Markus Kummerer 2 / 19 State of the Art Shading

Markus Kummerer 3 / 19 Overview n RenderMan Interface n Shape vs. Shading n Types of Shaders n Shading Language n Examples n Interactive Multi-Pass Shading

Markus Kummerer 4 / 19 RenderMan Interface n Powerful set of primitive surface types n Quadric surfaces n Polygons n Parametric surfaces n Hierarchical modeling, geometry n Constructive solid geometry n Camera model n Generalized shading model

Markus Kummerer 5 / 19 Shape vs. Shading n Shape n Geometric configuration of objects n Shading n Calculates the appearance of an object in a scene under a set of light sources n Result defined by u Colors of the surface and the light source(s) u Position and orientation of the surface relative to the light u Roughness of the surface

Markus Kummerer 6 / 19 Shading Pipeline n Three basic parts of the shading process n Emission at the light source n Interaction of the light with the surface n Atmospheric effects between the surface and the viewpoint

Markus Kummerer 7 / 19 Types of Shaders n RenderMan Interface supports n Light source shaders n Surface shaders n Volume shaders n Transformation shaders n Displacement shaders n Imager shaders

Markus Kummerer 8 / 19 Light Source Shader n Calculates the intensity and color of light sent by the light source to a point on a surface

Markus Kummerer 9 / 19 Surface Shader n Determines the color of light reflecting from a point on a surface in a particular direction

Markus Kummerer 10 / 19 Volume Shader n Generalizes the idea of atmosphere affecting light passing through space between a surface and the eye

Markus Kummerer 11 / 19 Shading Language n Orthogonal definition n Rendering environment n Special data types n Uniform and varying variables n Integration constructs n Filtered map access n Function library

Markus Kummerer 12 / 19 Examples

Markus Kummerer 13 / 19 Example: Surface Shader

Markus Kummerer 14 / 19 Example: Surface Shader

Markus Kummerer 15 / 19 Example: Displacement Shader

Markus Kummerer 16 / 19 Interactive Programmable Shading n OpenGL acts as an assembly language for shader execution n Compiler is introduced between the application and the graphics library

Markus Kummerer 17 / 19 Interactive Programmable Shading n Results

Markus Kummerer 18 / 19 Conclusion n Shading in software n Common technique for production animation n Offers generalized shading models n Provides a highly flexible approach n But is not interactive... n Shading in hardware is needed for interactivity

Markus Kummerer 19 / 19 Hope you are delighted, too