Fragment
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A [[fragment]] is a rendering concept which is roughly analogous to a single pixel on the output display (as opposed to a [[texel]] on an input texture). In practice, there is not a 1:1 mapping between fragments and device pixels for a large variety of reasons, the most obvious of which is anti-aliasing (which introduces additional fragments for some pixels). | A [[fragment]] is a rendering concept which is roughly analogous to a single pixel on the output display (as opposed to a [[texel]] on an input texture). In practice, there is not a 1:1 mapping between fragments and device pixels for a large variety of reasons, the most obvious of which is anti-aliasing (which introduces additional fragments for some pixels). | ||
| − | When rendering a given [[ | + | When rendering a given [[polygon]], the fragment shader is run once per fragment hit (with the possible exception of fragments that are [[early z-cull]]ed). |
When a fragment is hit by multiple overlapping primitives, [[overdraw]] occurs. This is considered a waste of GPU performance and should be minimized. | When a fragment is hit by multiple overlapping primitives, [[overdraw]] occurs. This is considered a waste of GPU performance and should be minimized. | ||
[[Category:Texture mapping]] | [[Category:Texture mapping]] | ||
Latest revision as of 14:08, 17 January 2018
A fragment is a rendering concept which is roughly analogous to a single pixel on the output display (as opposed to a texel on an input texture). In practice, there is not a 1:1 mapping between fragments and device pixels for a large variety of reasons, the most obvious of which is anti-aliasing (which introduces additional fragments for some pixels).
When rendering a given polygon, the fragment shader is run once per fragment hit (with the possible exception of fragments that are early z-culled).
When a fragment is hit by multiple overlapping primitives, overdraw occurs. This is considered a waste of GPU performance and should be minimized.
