} \
}
-/* As above, but CI mode (XXX try to merge someday) */
-#define FOG_LOOP_CI(FOG_FUNC) \
-if (span->arrayAttribs & FRAG_BIT_FOGC) { \
- GLuint i; \
- for (i = 0; i < span->end; i++) { \
- const GLfloat fogCoord = span->array->attribs[FRAG_ATTRIB_FOGC][i][0]; \
- const GLfloat c = FABSF(fogCoord); \
- GLfloat f; \
- FOG_FUNC(f, c); \
- f = CLAMP(f, 0.0F, 1.0F); \
- index[i] = (GLuint) ((GLfloat) index[i] + (1.0F - f) * fogIndex); \
- } \
-} \
-else { \
- const GLfloat fogStep = span->attrStepX[FRAG_ATTRIB_FOGC][0]; \
- GLfloat fogCoord = span->attrStart[FRAG_ATTRIB_FOGC][0]; \
- const GLfloat wStep = span->attrStepX[FRAG_ATTRIB_WPOS][3]; \
- GLfloat w = span->attrStart[FRAG_ATTRIB_WPOS][3]; \
- GLuint i; \
- for (i = 0; i < span->end; i++) { \
- const GLfloat c = FABSF(fogCoord) / w; \
- GLfloat f; \
- FOG_FUNC(f, c); \
- f = CLAMP(f, 0.0F, 1.0F); \
- index[i] = (GLuint) ((GLfloat) index[i] + (1.0F - f) * fogIndex); \
- fogCoord += fogStep; \
- w += wStep; \
- } \
-}
-
-
-
/**
* Apply fog to a span of RGBA pixels.
* The fog value are either in the span->array->fog array or interpolated from
}
}
}
-
-
-/**
- * As above, but color index mode.
- */
-void
-_swrast_fog_ci_span( const GLcontext *ctx, SWspan *span )
-{
- const SWcontext *swrast = CONST_SWRAST_CONTEXT(ctx);
- const GLuint fogIndex = (GLuint) ctx->Fog.Index;
- GLuint *index = span->array->index;
-
- ASSERT(swrast->_FogEnabled);
- ASSERT(span->arrayMask & SPAN_INDEX);
-
- /* we need to compute fog blend factors */
- if (swrast->_PreferPixelFog) {
- /* The span's fog values are fog coordinates, now compute blend factors
- * and blend the fragment colors with the fog color.
- */
- switch (ctx->Fog.Mode) {
- case GL_LINEAR:
- {
- const GLfloat fogEnd = ctx->Fog.End;
- const GLfloat fogScale = (ctx->Fog.Start == ctx->Fog.End)
- ? 1.0F : 1.0F / (ctx->Fog.End - ctx->Fog.Start);
- FOG_LOOP_CI(LINEAR_FOG);
- }
- break;
- case GL_EXP:
- {
- const GLfloat density = -ctx->Fog.Density;
- FOG_LOOP_CI(EXP_FOG);
- }
- break;
- case GL_EXP2:
- {
- const GLfloat negDensitySquared = -ctx->Fog.Density * ctx->Fog.Density;
- FOG_LOOP_CI(EXP2_FOG);
- }
- break;
- default:
- _mesa_problem(ctx, "Bad fog mode in _swrast_fog_ci_span");
- return;
- }
- }
- else {
- /* The span's fog start/step/array values are blend factors in [0,1].
- * They were previously computed per-vertex.
- */
- FOG_LOOP_CI(BLEND_FOG);
- }
-}