The document summarizes a lecture on further details of the graphics pipeline. It discusses how triangles described by vertex positions in normalized device coordinates are rasterized into pixels on the screen. The lecture covers oriented edge equations, being inside a triangle, rasterization approaches like scanline rasterization, and basic fragment shading through color interpolation. Homework status and the lecturer's office hours are also provided.

1. CS 354 More Graphics Pipeline Mark Kilgard University of Texas January 24, 2012

9. A Simplified Graphics Pipeline Application Vertex batching & assembly Triangle assembly Triangle clipping Triangle rasterization Fragment shading Depth testing Color update Application- OpenGL API boundary Framebuffer NDC to window space Got to here in last lecture Depth buffer

13. Oriented Edge Equation Concept

16. 7 Cases, Only 1 Inside the Triangle +-+ ++- -++ +++ -+- --+ +-- ( x , y ) E i ( x , y ) = A i x + B i y + C i (Projective formulation allows for the 8 th case as well)

39. Back Face Culling Example Torus drawn in wire-frame without back face culling Notice considerable extraneous triangles that would normally be occluded Torus drawn in wire-frame with back face culling By culling back-facing (negative signed area) triangles, fewer triangles are rasterized

46. Another View of the Graphics Pipeline Geometry Program 3D Application or Game OpenGL API GPU Front End Vertex Assembly Vertex Shader Clipping, Setup, and Rasterization Fragment Shader Texture Fetch Raster Operations Framebuffer Access Memory Interface CPU – GPU Boundary OpenGL 3.3 Attribute Fetch Primitive Assembly Parameter Buffer Read programmable fixed-function Legend For future lectures…