arb-glsl workgroup Update

1. arb-glsl workgroupUpdate Bill Licea-Kane ATI Research, Inc.

2. arb-glsl workgroupOpenGL Shading Language • OpenGL Shading Language • OpenGL ES Shading Language • EVOLVING TOGETHER IN PARALLEL

3. arb-glsl workgroupOpenGL Shading Language #version 120 • Can link shaders with mixed versions • Special Variables • Qualifiers • Minor changes (some backward incompatible) • Names • Function Signatures • Arrays • Matrices • ARB_texture_shader_lod

4. arb-glsl workgroupOpenGL Shading Language • built-in fragment special variables • Based on OpenGL ES 2.0 • Values are undefined if GL_POINT_SPRITE disabled gl_PointCoord;

5. arb-glsl workgroupOpenGL Shading Language • qualifier vec4 centroid varying Texcoord;

6. arb-glsl workgroupOpenGL Shading Language • Names – slight changes from #version 110 • C++ like • Names hide names of all types • Functions, Variables, Structures • Can declare names within a scope • Exception – local functions declarations disallowed • Exception – can not redeclare within a scope • Built-in functions in “outermost scope” • A local name hides *ALL* outer names

7. arb-glsl workgroupOpenGL Shading Language • Example #version 120 // ... vec4 texture2D( sampler2D s, vec4 P ) { return vec4( 1.0, 0.0, 1.0, 1.0 ); } // ... vec4 texture2D = texture2D( tex0, P.st );

8. arb-glsl workgroupOpenGL Shading Language • Signature matching • First try to find an exact match • Else try limited implicit constructors: • int  float • ivec2  vec2 • ivec3  vec3 • ivec4  vec4 • If multiple implicit matches, error

9. arb-glsl workgroupOpenGL Shading Language • Arrays • Now first class • ==, !=, = (but must have explicit size) • Array constructors float[7]( 0.0,1.0,2.0,3.0,4.0,5.0,6.0 ) float[]( 0.0,1.0,2.0,3.0,4.0,5.0,6.0 ) float a[] = float[]( 0.0, 1.0, 2.0 );

10. arb-glsl workgroupOpenGL Shading Language • Matrices • non-square permitted mat2x3 // 2 columns by 3 rows outerProduct() transpose() • Additional constructors

11. arb-glsl workgroupOpenGL Shading Language • built-in functions • Based on ATI_shader_texture_lod texture2DLod( sampler2D s, vec2 P, float Lod ); texture2DGradARB( sampler2D s, vec2 P, vec2 dPdx, vec2 dPdy ); texture2DProjGradARB( sampler2D s, vec2 P, vec2 dPdx, vec2 dPdy );

14. arb-glsl workgroupPixel grids and area operators