diff options
Diffstat (limited to 'src/gallium/drivers')
-rw-r--r-- | src/gallium/drivers/softpipe/sp_tex_sample.c | 53 |
1 files changed, 32 insertions, 21 deletions
diff --git a/src/gallium/drivers/softpipe/sp_tex_sample.c b/src/gallium/drivers/softpipe/sp_tex_sample.c index f74b86b3c2..2092a69740 100644 --- a/src/gallium/drivers/softpipe/sp_tex_sample.c +++ b/src/gallium/drivers/softpipe/sp_tex_sample.c @@ -46,13 +46,18 @@ /* - * Note, the FRAC macro has to work perfectly. Otherwise you'll sometimes - * see 1-pixel bands of improperly weighted linear-filtered textures. + * Return fractional part of 'f'. Used for computing interpolation weights. + * Need to be careful with negative values. + * Note, if this function isn't perfect you'll sometimes see 1-pixel bands + * of improperly weighted linear-filtered textures. * The tests/texwrap.c demo is a good test. - * Also note, FRAC(x) doesn't truly return the fractional part of x for x < 0. - * Instead, if x < 0 then FRAC(x) = 1 - true_frac(x). */ -#define FRAC(f) ((f) - util_ifloor(f)) +static INLINE float +frac(float f) +{ + return f - util_ifloor(f); +} + /** @@ -99,10 +104,16 @@ lerp_3d(float a, float b, float c, /** - * If A is a signed integer, A % B doesn't give the right value for A < 0 - * (in terms of texture repeat). Just casting to unsigned fixes that. + * Compute coord % size for repeat wrap modes. + * Note that if coord is a signed integer, coord % size doesn't give + * the right value for coord < 0 (in terms of texture repeat). Just + * casting to unsigned fixes that. */ -#define REMAINDER(A, B) ((unsigned) (A) % (unsigned) (B)) +static INLINE int +repeat(int coord, unsigned size) +{ + return (int) ((unsigned) coord % size); +} /** @@ -122,7 +133,7 @@ wrap_nearest_repeat(const float s[4], unsigned size, int icoord[4]) /* i limited to [0,size-1] */ for (ch = 0; ch < 4; ch++) { int i = util_ifloor(s[ch] * size); - icoord[ch] = REMAINDER(i, size); + icoord[ch] = repeat(i, size); } } @@ -282,9 +293,9 @@ wrap_linear_repeat(const float s[4], unsigned size, uint ch; for (ch = 0; ch < 4; ch++) { float u = s[ch] * size - 0.5F; - icoord0[ch] = REMAINDER(util_ifloor(u), size); - icoord1[ch] = REMAINDER(icoord0[ch] + 1, size); - w[ch] = FRAC(u); + icoord0[ch] = repeat(util_ifloor(u), size); + icoord1[ch] = repeat(icoord0[ch] + 1, size); + w[ch] = frac(u); } } @@ -299,7 +310,7 @@ wrap_linear_clamp(const float s[4], unsigned size, u = u * size - 0.5f; icoord0[ch] = util_ifloor(u); icoord1[ch] = icoord0[ch] + 1; - w[ch] = FRAC(u); + w[ch] = frac(u); } } @@ -318,7 +329,7 @@ wrap_linear_clamp_to_edge(const float s[4], unsigned size, icoord0[ch] = 0; if (icoord1[ch] >= (int) size) icoord1[ch] = size - 1; - w[ch] = FRAC(u); + w[ch] = frac(u); } } @@ -335,7 +346,7 @@ wrap_linear_clamp_to_border(const float s[4], unsigned size, u = u * size - 0.5f; icoord0[ch] = util_ifloor(u); icoord1[ch] = icoord0[ch] + 1; - w[ch] = FRAC(u); + w[ch] = frac(u); } } @@ -359,7 +370,7 @@ wrap_linear_mirror_repeat(const float s[4], unsigned size, icoord0[ch] = 0; if (icoord1[ch] >= (int) size) icoord1[ch] = size - 1; - w[ch] = FRAC(u); + w[ch] = frac(u); } } @@ -378,7 +389,7 @@ wrap_linear_mirror_clamp(const float s[4], unsigned size, u -= 0.5F; icoord0[ch] = util_ifloor(u); icoord1[ch] = icoord0[ch] + 1; - w[ch] = FRAC(u); + w[ch] = frac(u); } } @@ -401,7 +412,7 @@ wrap_linear_mirror_clamp_to_edge(const float s[4], unsigned size, icoord0[ch] = 0; if (icoord1[ch] >= (int) size) icoord1[ch] = size - 1; - w[ch] = FRAC(u); + w[ch] = frac(u); } } @@ -424,7 +435,7 @@ wrap_linear_mirror_clamp_to_border(const float s[4], unsigned size, u -= 0.5F; icoord0[ch] = util_ifloor(u); icoord1[ch] = icoord0[ch] + 1; - w[ch] = FRAC(u); + w[ch] = frac(u); } } @@ -472,7 +483,7 @@ wrap_linear_unorm_clamp(const float s[4], unsigned size, float u = CLAMP(s[ch] - 0.5F, 0.0f, (float) size - 1.0f); icoord0[ch] = util_ifloor(u); icoord1[ch] = icoord0[ch] + 1; - w[ch] = FRAC(u); + w[ch] = frac(u); } } @@ -489,7 +500,7 @@ wrap_linear_unorm_clamp_to_border(const float s[4], unsigned size, icoord1[ch] = icoord0[ch] + 1; if (icoord1[ch] > (int) size - 1) icoord1[ch] = size - 1; - w[ch] = FRAC(u); + w[ch] = frac(u); } } |