Table of Contents Glide Programming Guide
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Glossaryaliasing Rendering artifacts that occur when a continuous function is discretely sampled or sub-sampled. Two common types of aliasing are polygonal aliasing and texture aliasing. Polygonal aliasing is a rendering artifact that occurs when rasterization applies color to a pixel without considering how much of the pixel is covered by the triangle. Along the edges of the triangle, only a portion of the pixel is likely to be covered by the triangle. An aliased triangle will have jagged edges. Texture aliasing is a rendering artifact that occurs when a texture map is not sampled frequently enough or when the texel area covered by a pixel is not accounted for. See anti-aliasing. alpha The A in an RGBA color. The alpha component is never displayed. It is a multiplier used to describe transparency and controls the blending of overlapping colors. See blending. ambient light One of the components of a lighting model. Ambient light seems to come from all directions rather than from a specific source. Back lighting in a room is an example. It scatters in all directions after striking a surface, as does diffuse light. See diffuse, emitted, and specular light. animation Generating and displaying a scene as the viewpoint and/or objects change position to give the illusion of motion. anti-aliasing Techniques for eliminating aliasing. For polygonal aliasing, a rendering technique that accounts for fractional coverage of a pixel when assigning it a color, thereby reducing or eliminating the jagged edges that characterize an aliased rendering. For texture aliasing, a rendering technique that accounts for the areas of texels covered by a pixel. See aliasing. API Application program interface. ASIC Application-specific integrated circuit. back face culling The process of eliminating back facing triangles. A triangle has two sides, front and back, with only one side visible at a time. The sign of the area of the triangle determines which side is visible and can be used to eliminate back facing triangles before they are rendered. Download 6.22 Mb. Share with your friends:
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