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authorLuca Barbieri <luca@luca-barbieri.com>2009-07-15 11:34:36 -0600
committerBrian Paul <brianp@vmware.com>2009-07-15 11:34:36 -0600
commit6b7b13b5ebcebdca38264d165a95fd22887b90c7 (patch)
treeea15b5df4924c834826ae59d4e1d92e40af770e0 /src/gallium/drivers/softpipe
parentd970313b66b3aab3e3d12c65882febcc7c9091a8 (diff)
softpipe: limit blend results to [0,1]
Diffstat (limited to 'src/gallium/drivers/softpipe')
-rw-r--r--src/gallium/drivers/softpipe/sp_quad_blend.c42
1 files changed, 30 insertions, 12 deletions
diff --git a/src/gallium/drivers/softpipe/sp_quad_blend.c b/src/gallium/drivers/softpipe/sp_quad_blend.c
index e134e44337..b1e18805c7 100644
--- a/src/gallium/drivers/softpipe/sp_quad_blend.c
+++ b/src/gallium/drivers/softpipe/sp_quad_blend.c
@@ -72,6 +72,24 @@ do { \
R[3] = A[3] - B[3]; \
} while (0)
+/** Add and limit result to ceiling of 1.0 */
+#define VEC4_ADD_SAT(R, A, B) \
+do { \
+ R[0] = A[0] + B[0]; if (R[0] > 1.0f) R[0] = 1.0f; \
+ R[1] = A[1] + B[1]; if (R[1] > 1.0f) R[1] = 1.0f; \
+ R[2] = A[2] + B[2]; if (R[2] > 1.0f) R[2] = 1.0f; \
+ R[3] = A[3] + B[3]; if (R[3] > 1.0f) R[3] = 1.0f; \
+} while (0)
+
+/** Subtract and limit result to floor of 0.0 */
+#define VEC4_SUB_SAT(R, A, B) \
+do { \
+ R[0] = A[0] - B[0]; if (R[0] < 0.0f) R[0] = 0.0f; \
+ R[1] = A[1] - B[1]; if (R[1] < 0.0f) R[1] = 0.0f; \
+ R[2] = A[2] - B[2]; if (R[2] < 0.0f) R[2] = 0.0f; \
+ R[3] = A[3] - B[3]; if (R[3] < 0.0f) R[3] = 0.0f; \
+} while (0)
+
#define VEC4_MUL(R, A, B) \
do { \
R[0] = A[0] * B[0]; \
@@ -676,19 +694,19 @@ blend_quad(struct quad_stage *qs, struct quad_header *quad)
*/
switch (softpipe->blend->rgb_func) {
case PIPE_BLEND_ADD:
- VEC4_ADD(quadColor[0], source[0], dest[0]); /* R */
- VEC4_ADD(quadColor[1], source[1], dest[1]); /* G */
- VEC4_ADD(quadColor[2], source[2], dest[2]); /* B */
+ VEC4_ADD_SAT(quadColor[0], source[0], dest[0]); /* R */
+ VEC4_ADD_SAT(quadColor[1], source[1], dest[1]); /* G */
+ VEC4_ADD_SAT(quadColor[2], source[2], dest[2]); /* B */
break;
case PIPE_BLEND_SUBTRACT:
- VEC4_SUB(quadColor[0], source[0], dest[0]); /* R */
- VEC4_SUB(quadColor[1], source[1], dest[1]); /* G */
- VEC4_SUB(quadColor[2], source[2], dest[2]); /* B */
+ VEC4_SUB_SAT(quadColor[0], source[0], dest[0]); /* R */
+ VEC4_SUB_SAT(quadColor[1], source[1], dest[1]); /* G */
+ VEC4_SUB_SAT(quadColor[2], source[2], dest[2]); /* B */
break;
case PIPE_BLEND_REVERSE_SUBTRACT:
- VEC4_SUB(quadColor[0], dest[0], source[0]); /* R */
- VEC4_SUB(quadColor[1], dest[1], source[1]); /* G */
- VEC4_SUB(quadColor[2], dest[2], source[2]); /* B */
+ VEC4_SUB_SAT(quadColor[0], dest[0], source[0]); /* R */
+ VEC4_SUB_SAT(quadColor[1], dest[1], source[1]); /* G */
+ VEC4_SUB_SAT(quadColor[2], dest[2], source[2]); /* B */
break;
case PIPE_BLEND_MIN:
VEC4_MIN(quadColor[0], source[0], dest[0]); /* R */
@@ -709,13 +727,13 @@ blend_quad(struct quad_stage *qs, struct quad_header *quad)
*/
switch (softpipe->blend->alpha_func) {
case PIPE_BLEND_ADD:
- VEC4_ADD(quadColor[3], source[3], dest[3]); /* A */
+ VEC4_ADD_SAT(quadColor[3], source[3], dest[3]); /* A */
break;
case PIPE_BLEND_SUBTRACT:
- VEC4_SUB(quadColor[3], source[3], dest[3]); /* A */
+ VEC4_SUB_SAT(quadColor[3], source[3], dest[3]); /* A */
break;
case PIPE_BLEND_REVERSE_SUBTRACT:
- VEC4_SUB(quadColor[3], dest[3], source[3]); /* A */
+ VEC4_SUB_SAT(quadColor[3], dest[3], source[3]); /* A */
break;
case PIPE_BLEND_MIN:
VEC4_MIN(quadColor[3], source[3], dest[3]); /* A */