This patch series adds support for the GLSL 1.30 interpolation qualifiers 'flat', 'noperspective', and 'smooth' to i965 Gen6+.
There was already some support in Mesa core for these qualifiers, however, it did not distinguish correctly between 'smooth' and no interpolation qualifier at all, and it did not provide a reasonable mechanism for back-ends to determine which interpolation mode to use for a variable, or which interpolation modes are needed by the fragment shader as a whole. These deficiencies are addressed in patches 1-3. Note that there is some overlap in the funcationality of patches 2 and 3. Patch 2 introduces ir_varible::determine_interpolation_mode(), which tells how a single variable should be interpolated. Patch 3 introduces bitfields which tell how all fragment shader inputs should be interpolated. Strictly speaking, this is redundant. However, for code that deals with GLSL IR variables directly (such as the i965 fragment-shader back-end), it is far easier to use ir_varible::determine_interpolation_mode(), and for code that doesn't deal with the GLSL IR variables (such as the i965's SF and CLIP setup functions), it is far easier to use bitfields. So it seemed prudent to make both mechanisms available in core mesa. The remaining patches add interpolation qualifier support to the i965 back-end. This required modifying the CLIP stage to output noperspective barycentric coordinates when needed, modifying the SF stage to perform flat interpolation at the right time, and modifying the FS back-end to allocate registers for noperspective barycentric coordinates and use them when appropriate. [PATCH 1/8] glsl: Distinguish between no interpolation qualifier and 'smooth' [PATCH 2/8] glsl: add ir_variable::determine_interpolation_mode() function. [PATCH 3/8] mesa: Add interpolation override bitfields. [PATCH 4/8] i965/fs: Fix split_virtual_grfs() when delta_xy not in a virtual register. [PATCH 5/8] i965/gen6+: Parameterize barycentric interpolation modes. [PATCH 6/8] i965/fs: use determine_interpolation_mode(). [PATCH 7/8] i965/gen6+: Rename GEN6_CLIP_BARYCENTRIC_ENABLE. [PATCH 8/8] i965/gen6+: Add support for noperspective interpolation. _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
