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authorIan Romanick <[email protected]>2016-08-18 10:57:44 +0100
committerIan Romanick <[email protected]>2016-08-26 15:03:14 -0700
commita7d92c3c0b0df1a5e8be3f8208868828043ab630 (patch)
treee4089893486bf8982c105c723e1cc98af4e02fdc /src/mesa/drivers/dri
parentf926cf5bd0ade3273b320ca4483d826fcfe20bbb (diff)
nouveau: Fix non-1x post-scale factor with DOT3 combiner
Fixes long standing bug on NV10 and NV20 where using a non-1x RGB or A post-scale with GL_DOT3_RGB or GL_DOT3_RGBA texture environment would not work. The old combiner math uses HALF_BIAS_NORMAL and HALF_BIAS_NEGATE. The GL_NV_register_combiners defines these as HALF_BIAS_NORMAL_NV max(0.0, e) - 0.5 HALF_BIAS_NEGATE_NV -max(0.0, e) + 0.5 In order to get the correct result from the dot-product, the intermediate dot-product must be multiplied by 4. This is a literal implementation of the GL_ARB_texture_env_dot3 spec. It also requires using the register combiner post-scale. As a result, the post-scale cannot be used for the post-scale set by the application. The new combiner math uses EXPAND_NORMAL and EXPAND_NEGATE. The GL_NV_register_combiners defines these as EXPAND_NORMAL_NV 2.0 * max(0.0, e) - 1.0 EXPAND_NEGATE_NV -2.0 * max(0.0, e) + 1.0 Since this fully expands the value to [-1, 1] range, the intermediate dot-product result is the desired value. This leaves the register combiner post-scale available for application use. NOTE: I have not actually tested this. Signed-off-by: Ian Romanick <[email protected]> Acked-by: Ilia Mirkin <[email protected]>
Diffstat (limited to 'src/mesa/drivers/dri')
-rw-r--r--src/mesa/drivers/dri/nouveau/nv10_state_frag.c18
1 files changed, 8 insertions, 10 deletions
diff --git a/src/mesa/drivers/dri/nouveau/nv10_state_frag.c b/src/mesa/drivers/dri/nouveau/nv10_state_frag.c
index c007c6c6bc2..e78eac353bd 100644
--- a/src/mesa/drivers/dri/nouveau/nv10_state_frag.c
+++ b/src/mesa/drivers/dri/nouveau/nv10_state_frag.c
@@ -135,7 +135,7 @@ get_input_source(struct combiner_state *rc, int source)
/* Get the RC input mapping for the specified texture_env_combine
* operand, possibly inverted or biased. */
#define INVERT 0x1
-#define HALF_BIAS 0x2
+#define NORMALIZE 0x2
static uint32_t
get_input_mapping(struct combiner_state *rc, int operand, int flags)
@@ -148,12 +148,12 @@ get_input_mapping(struct combiner_state *rc, int operand, int flags)
map |= RC_IN_USAGE(ALPHA);
if (is_negative_operand(operand) == !(flags & INVERT))
- map |= flags & HALF_BIAS ?
- RC_IN_MAPPING(HALF_BIAS_NEGATE) :
+ map |= flags & NORMALIZE ?
+ RC_IN_MAPPING(EXPAND_NEGATE) :
RC_IN_MAPPING(UNSIGNED_INVERT);
else
- map |= flags & HALF_BIAS ?
- RC_IN_MAPPING(HALF_BIAS_NORMAL) :
+ map |= flags & NORMALIZE ?
+ RC_IN_MAPPING(EXPAND_NORMAL) :
RC_IN_MAPPING(UNSIGNED_IDENTITY);
return map;
@@ -270,12 +270,10 @@ setup_combiner(struct combiner_state *rc)
case GL_DOT3_RGB:
case GL_DOT3_RGBA:
- INPUT_ARG(rc, A, 0, HALF_BIAS);
- INPUT_ARG(rc, B, 1, HALF_BIAS);
+ INPUT_ARG(rc, A, 0, NORMALIZE);
+ INPUT_ARG(rc, B, 1, NORMALIZE);
- rc->out = RC_OUT_DOT_AB | RC_OUT_SCALE_4;
-
- assert(!rc->logscale);
+ rc->out = RC_OUT_DOT_AB;
break;
default: