| 摘要 |
A graphics processor includes a vertex shader that processes input attribute values from a vertex buffer 26 to generate output vertex shaded attribute values 28 to be used by a rasteriser/fragment shader 22 of the graphics processor when processing an image for display. The system recognizes when a vertex shader output attribute value to be generated from a vertex shader input attribute value by the vertex shader 20 will be a copy of the vertex shader input attribute value from which it is to be generated. In this event, the vertex shader 20 does not generate the copy vertex shader output attribute value, but the rasteriser/fragment shader 22 instead processes the corresponding vertex shader input attribute value in place of the copy vertex shader output attribute value that would otherwise have been generated by the vertex shader 20. An additional invention relates to the association of meta-information with the attributes used in the vertex shading stage for use when loading or storing the attributes. The meta-information may relate to whether the output attribute should be written to memory or not and/or the form of a test to determine whether such writing should take place and the parameters for such a test. |
