diff options
| author | Ian Romanick <[email protected]> | 2016-08-18 10:57:44 +0100 |
|---|---|---|
| committer | Ian Romanick <[email protected]> | 2016-08-26 15:03:14 -0700 |
| commit | a7d92c3c0b0df1a5e8be3f8208868828043ab630 (patch) | |
| tree | e4089893486bf8982c105c723e1cc98af4e02fdc /src/mesa/drivers/dri/nouveau | |
| parent | f926cf5bd0ade3273b320ca4483d826fcfe20bbb (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/nouveau')
| -rw-r--r-- | src/mesa/drivers/dri/nouveau/nv10_state_frag.c | 18 |
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: |