- /* Use the interpolation values */
-#if CHAN_TYPE == GL_FLOAT
- const GLfloat alphaStep = span->alphaStep;
- GLfloat alpha = span->alpha;
- ASSERT(span->interpMask & SPAN_RGBA);
- switch (ctx->Color.AlphaFunc) {
- case GL_LESS:
- for (i = 0; i < n; i++) {
- mask[i] &= (alpha < ref);
- alpha += alphaStep;
- }
- break;
- case GL_LEQUAL:
- for (i = 0; i < n; i++) {
- mask[i] &= (alpha <= ref);
- alpha += alphaStep;
- }
- break;
- case GL_GEQUAL:
- for (i = 0; i < n; i++) {
- mask[i] &= (alpha >= ref);
- alpha += alphaStep;
- }
- break;
- case GL_GREATER:
- for (i = 0; i < n; i++) {
- mask[i] &= (alpha > ref);
- alpha += alphaStep;
- }
- break;
- case GL_NOTEQUAL:
- for (i = 0; i < n; i++) {
- mask[i] &= (alpha != ref);
- alpha += alphaStep;
- }
- break;
- case GL_EQUAL:
- for (i = 0; i < n; i++) {
- mask[i] &= (alpha == ref);
- alpha += alphaStep;
- }
- break;
- case GL_ALWAYS:
- /* do nothing */
- return 1;
- case GL_NEVER:
- /* caller should check for zero! */
- span->writeAll = GL_FALSE;
- return 0;
- default:
- _mesa_problem( ctx, "Invalid alpha test in gl_alpha_test" );
- return 0;
+ /* Interpolate alpha values */
+ assert(span->interpMask & SPAN_RGBA);
+ if (span->array->ChanType == GL_UNSIGNED_BYTE) {
+ const GLfixed alphaStep = span->alphaStep;
+ GLfixed alpha = span->alpha;
+ GLubyte ref;
+ CLAMPED_FLOAT_TO_UBYTE(ref, ctx->Color.AlphaRef);
+ ALPHA_TEST(FixedToInt(alpha), alpha += alphaStep);