- constant_coef( setup, tri, slot, 1.0f - frontface, 0 );
- constant_coef( setup, tri, slot, 0.0f, 1 ); /* wasted */
- constant_coef( setup, tri, slot, 0.0f, 2 ); /* wasted */
- constant_coef( setup, tri, slot, 0.0f, 3 ); /* wasted */
+ /* convert TRUE to 1.0 and FALSE to -1.0 */
+ if (usage_mask & TGSI_WRITEMASK_X)
+ constant_coef( setup, tri, slot, 2.0f * frontface - 1.0f, 0 );
+
+ if (usage_mask & TGSI_WRITEMASK_Y)
+ constant_coef( setup, tri, slot, 0.0f, 1 ); /* wasted */
+
+ if (usage_mask & TGSI_WRITEMASK_Z)
+ constant_coef( setup, tri, slot, 0.0f, 2 ); /* wasted */
+
+ if (usage_mask & TGSI_WRITEMASK_W)
+ constant_coef( setup, tri, slot, 0.0f, 3 ); /* wasted */