3D graphics eBook - Course Materials Repository

Graphics pipeline 54
References
1. Graphics pipeline. (n.d.). Computer Desktop Encyclopedia. Retrieved December 13, 2005, from Answers.com:
[1]
2. Raster Graphics and Color [2] 2004 by Greg Humphreys at the University of Virginia
[1] http:/ / www. answers. com/ topic/ graphics-pipeline
[2] http:/ / www. cs. virginia. edu/ ~gfx/ Courses/ 2004/ Intro. Fall. 04/ handouts/ 01-raster. pdf
External links
• MIT OpenCourseWare Computer Graphics, Fall 2003 (http:/ / ocw. mit. edu/ courses/
electrical-engineering-and-computer-science/ 6-837-computer-graphics-fall-2003/ )
• ExtremeTech 3D Pipeline Tutorial (http:/ / www. extremetech. com/ computing/
49076-extremetech-3d-pipeline-tutorial)
• http:/ / developer. nvidia. com/
• http:/ / www. atitech. com/ developer/
Hidden line removal
Hidden line removal is an extension of wireframe model rendering
where lines (or segments of lines) covered by surfaces are not drawn.
This is not the same as hidden face removal since this involves depth
and occlusion while the other involves normals.
Algorithms
A commonly used algorithm to implement it is Arthur Appel's
algorithm. [1] This algorithm works by propagating the visibility from a
segment with a known visibility to a segment whose visibility is yet to
be determined. Certain pathological cases exist that can make this
algorithm difficult to implement. Those cases are:
1. Vertices on edges;
2. Edges on vertices;
3. Edges on edges.
Line removal technique in action
This algorithm is unstable because an error in visibility will be propagated to subsequent nodes (although there are
ways to compensate for this problem). [2]