By Lars Weinand / Thomas Pabst (Tom´s Hardware Guide)

New Pixel Shaders (?)

You can find more detailed information about pixel shaders in this article.

The pixel shader's functionality was also extended from the previous version's. The new chip supports pixel shader implementaions 1.2 and 1.3, but ATi's version 1.4 was not included.

A quick rundown of the new modes:

OFFSET_PROJECTIVE_TEXTURE_2D_NV
OFFSET_PROJECTIVE_TEXTURE_2D_SCALE_NV
OFFSET_PROJECTIVE_TEXTURE_RECTANGLE_NV
OFFSET_PROJECTIVE_TEXTURE_RECTANGLE_SCALE_NV
OFFSET_HILO_TEXTURE_2D_NV
OFFSET_HILO_TEXTURE_RECTANGLE_NV
OFFSET_HILO_PROJECTIVE_TEXTURE_2D_NV
OFFSET_HILO_PROJECTIVE_TEXTURE_RECTANGLE_NV
DEPENDENT_HILO_TEXTURE_2D_NV
DEPENDENT_RGB_TEXTURE_3D_NV
DEPENDENT_RGB_TEXTURE_CUBE_MAP_NV
DOT_PRODUCT_TEXTURE_1D_NV
DOT_PRODUCT_PASS_THROUGH_NV
DOT_PRODUCT_AFFINE_DEPTH_REPLACE_NV

Explaining each of these modes in detail would take far too long and would turn into a technical treatise, so let me give you an example instead. The GeForce4 TI now supports Z-axis corrected bump mapping. Using this technique eliminates jagged egdes found where mapped objects overlap with other objects, for example where water (bump mapping) touches land.

Another improvement is the support for DXT1 compressed textures, as you can see in our screenshots.

Finally, the rendering pipelines have also been tuned, considerably increasing the speed with which three or four textures can be applied to a pixel.

Copyright: 06.02.2002 -   RIVA Station 2002 - Lars Weinand
No Copy without Permission!

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