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Diffstat (limited to 'src/mesa/swrast/s_texfilter.c')
| -rw-r--r-- | src/mesa/swrast/s_texfilter.c | 2782 |
1 files changed, 2782 insertions, 0 deletions
diff --git a/src/mesa/swrast/s_texfilter.c b/src/mesa/swrast/s_texfilter.c new file mode 100644 index 0000000000..7435690db0 --- /dev/null +++ b/src/mesa/swrast/s_texfilter.c @@ -0,0 +1,2782 @@ +/* + * Mesa 3-D graphics library + * Version: 6.5 + * + * Copyright (C) 1999-2005 Brian Paul All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN + * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + + +#include "glheader.h" +#include "context.h" +#include "colormac.h" +#include "imports.h" +#include "texformat.h" + +#include "s_context.h" +#include "s_texfilter.h" + + +/** + * Constants for integer linear interpolation. + */ +#define ILERP_SCALE 65536.0F +#define ILERP_SHIFT 16 + + +/** + * Linear interpolation macros + */ +#define LERP(T, A, B) ( (A) + (T) * ((B) - (A)) ) +#define ILERP(IT, A, B) ( (A) + (((IT) * ((B) - (A))) >> ILERP_SHIFT) ) + + +/** + * Do 2D/biliner interpolation of float values. + * v00, v10, v01 and v11 are typically four texture samples in a square/box. + * a and b are the horizontal and vertical interpolants. + * It's important that this function is inlined when compiled with + * optimization! If we find that's not true on some systems, convert + * to a macro. + */ +static INLINE GLfloat +lerp_2d(GLfloat a, GLfloat b, + GLfloat v00, GLfloat v10, GLfloat v01, GLfloat v11) +{ + const GLfloat temp0 = LERP(a, v00, v10); + const GLfloat temp1 = LERP(a, v01, v11); + return LERP(b, temp0, temp1); +} + + +/** + * Do 2D/biliner interpolation of integer values. + * \sa lerp_2d + */ +static INLINE GLint +ilerp_2d(GLint ia, GLint ib, + GLint v00, GLint v10, GLint v01, GLint v11) +{ + /* fixed point interpolants in [0, ILERP_SCALE] */ + const GLint temp0 = ILERP(ia, v00, v10); + const GLint temp1 = ILERP(ia, v01, v11); + return ILERP(ib, temp0, temp1); +} + + +/** + * Do 3D/trilinear interpolation of float values. + * \sa lerp_2d + */ +static INLINE GLfloat +lerp_3d(GLfloat a, GLfloat b, GLfloat c, + GLfloat v000, GLfloat v100, GLfloat v010, GLfloat v110, + GLfloat v001, GLfloat v101, GLfloat v011, GLfloat v111) +{ + const GLfloat temp00 = LERP(a, v000, v100); + const GLfloat temp10 = LERP(a, v010, v110); + const GLfloat temp01 = LERP(a, v001, v101); + const GLfloat temp11 = LERP(a, v011, v111); + const GLfloat temp0 = LERP(b, temp00, temp10); + const GLfloat temp1 = LERP(b, temp01, temp11); + return LERP(c, temp0, temp1); +} + + +/** + * Do 3D/trilinear interpolation of integer values. + * \sa lerp_2d + */ +static INLINE GLint +ilerp_3d(GLint ia, GLint ib, GLint ic, + GLint v000, GLint v100, GLint v010, GLint v110, + GLint v001, GLint v101, GLint v011, GLint v111) +{ + /* fixed point interpolants in [0, ILERP_SCALE] */ + const GLint temp00 = ILERP(ia, v000, v100); + const GLint temp10 = ILERP(ia, v010, v110); + const GLint temp01 = ILERP(ia, v001, v101); + const GLint temp11 = ILERP(ia, v011, v111); + const GLint temp0 = ILERP(ib, temp00, temp10); + const GLint temp1 = ILERP(ib, temp01, temp11); + return ILERP(ic, temp0, temp1); +} + + +/** + * Do linear interpolation of colors. + */ +static INLINE void +lerp_rgba(GLchan result[4], GLfloat t, const GLchan a[4], const GLchan b[4]) +{ +#if CHAN_TYPE == GL_FLOAT + result[0] = LERP(t, a[0], b[0]); + result[1] = LERP(t, a[1], b[1]); + result[2] = LERP(t, a[2], b[2]); + result[3] = LERP(t, a[3], b[3]); +#elif CHAN_TYPE == GL_UNSIGNED_SHORT + result[0] = (GLchan) (LERP(t, a[0], b[0]) + 0.5); + result[1] = (GLchan) (LERP(t, a[1], b[1]) + 0.5); + result[2] = (GLchan) (LERP(t, a[2], b[2]) + 0.5); + result[3] = (GLchan) (LERP(t, a[3], b[3]) + 0.5); +#else + /* fixed point interpolants in [0, ILERP_SCALE] */ + const GLint it = IROUND_POS(t * ILERP_SCALE); + ASSERT(CHAN_TYPE == GL_UNSIGNED_BYTE); + result[0] = ILERP(it, a[0], b[0]); + result[1] = ILERP(it, a[1], b[1]); + result[2] = ILERP(it, a[2], b[2]); + result[3] = ILERP(it, a[3], b[3]); +#endif +} + + +/** + * Do bilinear interpolation of colors. + */ +static INLINE void +lerp_rgba_2d(GLchan result[4], GLfloat a, GLfloat b, + const GLchan t00[4], const GLchan t10[4], + const GLchan t01[4], const GLchan t11[4]) +{ +#if CHAN_TYPE == GL_FLOAT + result[0] = lerp_2d(a, b, t00[0], t10[0], t01[0], t11[0]); + result[1] = lerp_2d(a, b, t00[1], t10[1], t01[1], t11[1]); + result[2] = lerp_2d(a, b, t00[2], t10[2], t01[2], t11[2]); + result[3] = lerp_2d(a, b, t00[3], t10[3], t01[3], t11[3]); +#elif CHAN_TYPE == GL_UNSIGNED_SHORT + result[0] = (GLchan) (lerp_2d(a, b, t00[0], t10[0], t01[0], t11[0]) + 0.5); + result[1] = (GLchan) (lerp_2d(a, b, t00[1], t10[1], t01[1], t11[1]) + 0.5); + result[2] = (GLchan) (lerp_2d(a, b, t00[2], t10[2], t01[2], t11[2]) + 0.5); + result[3] = (GLchan) (lerp_2d(a, b, t00[3], t10[3], t01[3], t11[3]) + 0.5); +#else + const GLint ia = IROUND_POS(a * ILERP_SCALE); + const GLint ib = IROUND_POS(b * ILERP_SCALE); + ASSERT(CHAN_TYPE == GL_UNSIGNED_BYTE); + result[0] = ilerp_2d(ia, ib, t00[0], t10[0], t01[0], t11[0]); + result[1] = ilerp_2d(ia, ib, t00[1], t10[1], t01[1], t11[1]); + result[2] = ilerp_2d(ia, ib, t00[2], t10[2], t01[2], t11[2]); + result[3] = ilerp_2d(ia, ib, t00[3], t10[3], t01[3], t11[3]); +#endif +} + + +/** + * Compute the remainder of a divided by b, but be careful with + * negative values so that GL_REPEAT mode works right. + */ +static INLINE GLint +repeat_remainder(GLint a, GLint b) +{ + if (a >= 0) + return a % b; + else + return (a + 1) % b + b - 1; +} + + +/** + * Used to compute texel locations for linear sampling. + * Input: + * wrapMode = GL_REPEAT, GL_CLAMP, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_BORDER + * S = texcoord in [0,1] + * SIZE = width (or height or depth) of texture + * Output: + * U = texcoord in [0, width] + * I0, I1 = two nearest texel indexes + */ +#define COMPUTE_LINEAR_TEXEL_LOCATIONS(wrapMode, S, U, SIZE, I0, I1) \ +{ \ + switch (wrapMode) { \ + case GL_REPEAT: \ + U = S * SIZE - 0.5F; \ + if (tObj->_IsPowerOfTwo) { \ + I0 = IFLOOR(U) & (SIZE - 1); \ + I1 = (I0 + 1) & (SIZE - 1); \ + } \ + else { \ + I0 = repeat_remainder(IFLOOR(U), SIZE); \ + I1 = repeat_remainder(I0 + 1, SIZE); \ + } \ + break; \ + case GL_CLAMP_TO_EDGE: \ + if (S <= 0.0F) \ + U = 0.0F; \ + else if (S >= 1.0F) \ + U = (GLfloat) SIZE; \ + else \ + U = S * SIZE; \ + U -= 0.5F; \ + I0 = IFLOOR(U); \ + I1 = I0 + 1; \ + if (I0 < 0) \ + I0 = 0; \ + if (I1 >= (GLint) SIZE) \ + I1 = SIZE - 1; \ + break; \ + case GL_CLAMP_TO_BORDER: \ + { \ + const GLfloat min = -1.0F / (2.0F * SIZE); \ + const GLfloat max = 1.0F - min; \ + if (S <= min) \ + U = min * SIZE; \ + else if (S >= max) \ + U = max * SIZE; \ + else \ + U = S * SIZE; \ + U -= 0.5F; \ + I0 = IFLOOR(U); \ + I1 = I0 + 1; \ + } \ + break; \ + case GL_MIRRORED_REPEAT: \ + { \ + const GLint flr = IFLOOR(S); \ + if (flr & 1) \ + U = 1.0F - (S - (GLfloat) flr); /* flr is odd */ \ + else \ + U = S - (GLfloat) flr; /* flr is even */ \ + U = (U * SIZE) - 0.5F; \ + I0 = IFLOOR(U); \ + I1 = I0 + 1; \ + if (I0 < 0) \ + I0 = 0; \ + if (I1 >= (GLint) SIZE) \ + I1 = SIZE - 1; \ + } \ + break; \ + case GL_MIRROR_CLAMP_EXT: \ + U = (GLfloat) fabs(S); \ + if (U >= 1.0F) \ + U = (GLfloat) SIZE; \ + else \ + U *= SIZE; \ + U -= 0.5F; \ + I0 = IFLOOR(U); \ + I1 = I0 + 1; \ + break; \ + case GL_MIRROR_CLAMP_TO_EDGE_EXT: \ + U = (GLfloat) fabs(S); \ + if (U >= 1.0F) \ + U = (GLfloat) SIZE; \ + else \ + U *= SIZE; \ + U -= 0.5F; \ + I0 = IFLOOR(U); \ + I1 = I0 + 1; \ + if (I0 < 0) \ + I0 = 0; \ + if (I1 >= (GLint) SIZE) \ + I1 = SIZE - 1; \ + break; \ + case GL_MIRROR_CLAMP_TO_BORDER_EXT: \ + { \ + const GLfloat min = -1.0F / (2.0F * SIZE); \ + const GLfloat max = 1.0F - min; \ + U = (GLfloat) fabs(S); \ + if (U <= min) \ + U = min * SIZE; \ + else if (U >= max) \ + U = max * SIZE; \ + else \ + U *= SIZE; \ + U -= 0.5F; \ + I0 = IFLOOR(U); \ + I1 = I0 + 1; \ + } \ + break; \ + case GL_CLAMP: \ + if (S <= 0.0F) \ + U = 0.0F; \ + else if (S >= 1.0F) \ + U = (GLfloat) SIZE; \ + else \ + U = S * SIZE; \ + U -= 0.5F; \ + I0 = IFLOOR(U); \ + I1 = I0 + 1; \ + break; \ + default: \ + _mesa_problem(ctx, "Bad wrap mode"); \ + } \ +} + + +/** + * Used to compute texel location for nearest sampling. + */ +#define COMPUTE_NEAREST_TEXEL_LOCATION(wrapMode, S, SIZE, I) \ +{ \ + switch (wrapMode) { \ + case GL_REPEAT: \ + /* s limited to [0,1) */ \ + /* i limited to [0,size-1] */ \ + I = IFLOOR(S * SIZE); \ + if (tObj->_IsPowerOfTwo) \ + I &= (SIZE - 1); \ + else \ + I = repeat_remainder(I, SIZE); \ + break; \ + case GL_CLAMP_TO_EDGE: \ + { \ + /* s limited to [min,max] */ \ + /* i limited to [0, size-1] */ \ + const GLfloat min = 1.0F / (2.0F * SIZE); \ + const GLfloat max = 1.0F - min; \ + if (S < min) \ + I = 0; \ + else if (S > max) \ + I = SIZE - 1; \ + else \ + I = IFLOOR(S * SIZE); \ + } \ + break; \ + case GL_CLAMP_TO_BORDER: \ + { \ + /* s limited to [min,max] */ \ + /* i limited to [-1, size] */ \ + const GLfloat min = -1.0F / (2.0F * SIZE); \ + const GLfloat max = 1.0F - min; \ + if (S <= min) \ + I = -1; \ + else if (S >= max) \ + I = SIZE; \ + else \ + I = IFLOOR(S * SIZE); \ + } \ + break; \ + case GL_MIRRORED_REPEAT: \ + { \ + const GLfloat min = 1.0F / (2.0F * SIZE); \ + const GLfloat max = 1.0F - min; \ + const GLint flr = IFLOOR(S); \ + GLfloat u; \ + if (flr & 1) \ + u = 1.0F - (S - (GLfloat) flr); /* flr is odd */ \ + else \ + u = S - (GLfloat) flr; /* flr is even */ \ + if (u < min) \ + I = 0; \ + else if (u > max) \ + I = SIZE - 1; \ + else \ + I = IFLOOR(u * SIZE); \ + } \ + break; \ + case GL_MIRROR_CLAMP_EXT: \ + { \ + /* s limited to [0,1] */ \ + /* i limited to [0,size-1] */ \ + const GLfloat u = (GLfloat) fabs(S); \ + if (u <= 0.0F) \ + I = 0; \ + else if (u >= 1.0F) \ + I = SIZE - 1; \ + else \ + I = IFLOOR(u * SIZE); \ + } \ + break; \ + case GL_MIRROR_CLAMP_TO_EDGE_EXT: \ + { \ + /* s limited to [min,max] */ \ + /* i limited to [0, size-1] */ \ + const GLfloat min = 1.0F / (2.0F * SIZE); \ + const GLfloat max = 1.0F - min; \ + const GLfloat u = (GLfloat) fabs(S); \ + if (u < min) \ + I = 0; \ + else if (u > max) \ + I = SIZE - 1; \ + else \ + I = IFLOOR(u * SIZE); \ + } \ + break; \ + case GL_MIRROR_CLAMP_TO_BORDER_EXT: \ + { \ + /* s limited to [min,max] */ \ + /* i limited to [0, size-1] */ \ + const GLfloat min = -1.0F / (2.0F * SIZE); \ + const GLfloat max = 1.0F - min; \ + const GLfloat u = (GLfloat) fabs(S); \ + if (u < min) \ + I = -1; \ + else if (u > max) \ + I = SIZE; \ + else \ + I = IFLOOR(u * SIZE); \ + } \ + break; \ + case GL_CLAMP: \ + /* s limited to [0,1] */ \ + /* i limited to [0,size-1] */ \ + if (S <= 0.0F) \ + I = 0; \ + else if (S >= 1.0F) \ + I = SIZE - 1; \ + else \ + I = IFLOOR(S * SIZE); \ + break; \ + default: \ + _mesa_problem(ctx, "Bad wrap mode"); \ + } \ +} + + +/* Power of two image sizes only */ +#define COMPUTE_LINEAR_REPEAT_TEXEL_LOCATION(S, U, SIZE, I0, I1) \ +{ \ + U = S * SIZE - 0.5F; \ + I0 = IFLOOR(U) & (SIZE - 1); \ + I1 = (I0 + 1) & (SIZE - 1); \ +} + + +/* + * Compute linear mipmap levels for given lambda. + */ +#define COMPUTE_LINEAR_MIPMAP_LEVEL(tObj, lambda, level) \ +{ \ + if (lambda < 0.0F) \ + level = tObj->BaseLevel; \ + else if (lambda > tObj->_MaxLambda) \ + level = (GLint) (tObj->BaseLevel + tObj->_MaxLambda); \ + else \ + level = (GLint) (tObj->BaseLevel + lambda); \ +} + + +/* + * Compute nearest mipmap level for given lambda. + */ +#define COMPUTE_NEAREST_MIPMAP_LEVEL(tObj, lambda, level) \ +{ \ + GLfloat l; \ + if (lambda <= 0.5F) \ + l = 0.0F; \ + else if (lambda > tObj->_MaxLambda + 0.4999F) \ + l = tObj->_MaxLambda + 0.4999F; \ + else \ + l = lambda; \ + level = (GLint) (tObj->BaseLevel + l + 0.5F); \ + if (level > tObj->_MaxLevel) \ + level = tObj->_MaxLevel; \ +} + + + +/* + * Note, the FRAC macro has to work perfectly. Otherwise 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) - IFLOOR(f)) + + + +/* + * Bitflags for texture border color sampling. + */ +#define I0BIT 1 +#define I1BIT 2 +#define J0BIT 4 +#define J1BIT 8 +#define K0BIT 16 +#define K1BIT 32 + + + +/* + * The lambda[] array values are always monotonic. Either the whole span + * will be minified, magnified, or split between the two. This function + * determines the subranges in [0, n-1] that are to be minified or magnified. + */ +static INLINE void +compute_min_mag_ranges( GLfloat minMagThresh, GLuint n, const GLfloat lambda[], + GLuint *minStart, GLuint *minEnd, + GLuint *magStart, GLuint *magEnd ) +{ + ASSERT(lambda != NULL); +#if 0 + /* Verify that lambda[] is monotonous. + * We can't really use this because the inaccuracy in the LOG2 function + * causes this test to fail, yet the resulting texturing is correct. + */ + if (n > 1) { + GLuint i; + printf("lambda delta = %g\n", lambda[0] - lambda[n-1]); + if (lambda[0] >= lambda[n-1]) { /* decreasing */ + for (i = 0; i < n - 1; i++) { + ASSERT((GLint) (lambda[i] * 10) >= (GLint) (lambda[i+1] * 10)); + } + } + else { /* increasing */ + for (i = 0; i < n - 1; i++) { + ASSERT((GLint) (lambda[i] * 10) <= (GLint) (lambda[i+1] * 10)); + } + } + } +#endif /* DEBUG */ + + /* since lambda is monotonous-array use this check first */ + if (lambda[0] <= minMagThresh && lambda[n-1] <= minMagThresh) { + /* magnification for whole span */ + *magStart = 0; + *magEnd = n; + *minStart = *minEnd = 0; + } + else if (lambda[0] > minMagThresh && lambda[n-1] > minMagThresh) { + /* minification for whole span */ + *minStart = 0; + *minEnd = n; + *magStart = *magEnd = 0; + } + else { + /* a mix of minification and magnification */ + GLuint i; + if (lambda[0] > minMagThresh) { + /* start with minification */ + for (i = 1; i < n; i++) { + if (lambda[i] <= minMagThresh) + break; + } + *minStart = 0; + *minEnd = i; + *magStart = i; + *magEnd = n; + } + else { + /* start with magnification */ + for (i = 1; i < n; i++) { + if (lambda[i] > minMagThresh) + break; + } + *magStart = 0; + *magEnd = i; + *minStart = i; + *minEnd = n; + } + } + +#if 0 + /* Verify the min/mag Start/End values + * We don't use this either (see above) + */ + { + GLint i; + for (i = 0; i < n; i++) { + if (lambda[i] > minMagThresh) { + /* minification */ + ASSERT(i >= *minStart); + ASSERT(i < *minEnd); + } + else { + /* magnification */ + ASSERT(i >= *magStart); + ASSERT(i < *magEnd); + } + } + } +#endif +} + + +/**********************************************************************/ +/* 1-D Texture Sampling Functions */ +/**********************************************************************/ + +/* + * Return the texture sample for coordinate (s) using GL_NEAREST filter. + */ +static void +sample_1d_nearest(GLcontext *ctx, + const struct gl_texture_object *tObj, + const struct gl_texture_image *img, + const GLfloat texcoord[4], GLchan rgba[4]) +{ + const GLint width = img->Width2; /* without border, power of two */ + GLint i; + (void) ctx; + + COMPUTE_NEAREST_TEXEL_LOCATION(tObj->WrapS, texcoord[0], width, i); + + /* skip over the border, if any */ + i += img->Border; + + if (i < 0 || i >= (GLint) img->Width) { + /* Need this test for GL_CLAMP_TO_BORDER mode */ + COPY_CHAN4(rgba, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i, 0, 0, rgba); + } +} + + + +/* + * Return the texture sample for coordinate (s) using GL_LINEAR filter. + */ +static void +sample_1d_linear(GLcontext *ctx, + const struct gl_texture_object *tObj, + const struct gl_texture_image *img, + const GLfloat texcoord[4], GLchan rgba[4]) +{ + const GLint width = img->Width2; + GLint i0, i1; + GLfloat u; + GLuint useBorderColor; + (void) ctx; + + COMPUTE_LINEAR_TEXEL_LOCATIONS(tObj->WrapS, texcoord[0], u, width, i0, i1); + + useBorderColor = 0; + if (img->Border) { + i0 += img->Border; + i1 += img->Border; + } + else { + if (i0 < 0 || i0 >= width) useBorderColor |= I0BIT; + if (i1 < 0 || i1 >= width) useBorderColor |= I1BIT; + } + + { + const GLfloat a = FRAC(u); + GLchan t0[4], t1[4]; /* texels */ + + /* fetch texel colors */ + if (useBorderColor & I0BIT) { + COPY_CHAN4(t0, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i0, 0, 0, t0); + } + if (useBorderColor & I1BIT) { + COPY_CHAN4(t1, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i1, 0, 0, t1); + } + + lerp_rgba(rgba, a, t0, t1); + } +} + + +static void +sample_1d_nearest_mipmap_nearest(GLcontext *ctx, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + ASSERT(lambda != NULL); + for (i = 0; i < n; i++) { + GLint level; + COMPUTE_NEAREST_MIPMAP_LEVEL(tObj, lambda[i], level); + sample_1d_nearest(ctx, tObj, tObj->Image[0][level], texcoord[i], rgba[i]); + } +} + + +static void +sample_1d_linear_mipmap_nearest(GLcontext *ctx, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + ASSERT(lambda != NULL); + for (i = 0; i < n; i++) { + GLint level; + COMPUTE_NEAREST_MIPMAP_LEVEL(tObj, lambda[i], level); + sample_1d_linear(ctx, tObj, tObj->Image[0][level], texcoord[i], rgba[i]); + } +} + + +static void +sample_1d_nearest_mipmap_linear(GLcontext *ctx, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + ASSERT(lambda != NULL); + for (i = 0; i < n; i++) { + GLint level; + COMPUTE_LINEAR_MIPMAP_LEVEL(tObj, lambda[i], level); + if (level >= tObj->_MaxLevel) { + sample_1d_nearest(ctx, tObj, tObj->Image[0][tObj->_MaxLevel], + texcoord[i], rgba[i]); + } + else { + GLchan t0[4], t1[4]; + const GLfloat f = FRAC(lambda[i]); + sample_1d_nearest(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0); + sample_1d_nearest(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1); + lerp_rgba(rgba[i], f, t0, t1); + } + } +} + + + +static void +sample_1d_linear_mipmap_linear(GLcontext *ctx, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + ASSERT(lambda != NULL); + for (i = 0; i < n; i++) { + GLint level; + COMPUTE_LINEAR_MIPMAP_LEVEL(tObj, lambda[i], level); + if (level >= tObj->_MaxLevel) { + sample_1d_linear(ctx, tObj, tObj->Image[0][tObj->_MaxLevel], + texcoord[i], rgba[i]); + } + else { + GLchan t0[4], t1[4]; + const GLfloat f = FRAC(lambda[i]); + sample_1d_linear(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0); + sample_1d_linear(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1); + lerp_rgba(rgba[i], f, t0, t1); + } + } +} + + + +static void +sample_nearest_1d( GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], const GLfloat lambda[], + GLchan rgba[][4] ) +{ + GLuint i; + struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel]; + (void) texUnit; + (void) lambda; + for (i=0;i<n;i++) { + sample_1d_nearest(ctx, tObj, image, texcoords[i], rgba[i]); + } +} + + + +static void +sample_linear_1d( GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], const GLfloat lambda[], + GLchan rgba[][4] ) +{ + GLuint i; + struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel]; + (void) texUnit; + (void) lambda; + for (i=0;i<n;i++) { + sample_1d_linear(ctx, tObj, image, texcoords[i], rgba[i]); + } +} + + +/* + * Given an (s) texture coordinate and lambda (level of detail) value, + * return a texture sample. + * + */ +static void +sample_lambda_1d( GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], + const GLfloat lambda[], GLchan rgba[][4] ) +{ + GLuint minStart, minEnd; /* texels with minification */ + GLuint magStart, magEnd; /* texels with magnification */ + GLuint i; + + ASSERT(lambda != NULL); + compute_min_mag_ranges(SWRAST_CONTEXT(ctx)->_MinMagThresh[texUnit], + n, lambda, &minStart, &minEnd, &magStart, &magEnd); + + if (minStart < minEnd) { + /* do the minified texels */ + const GLuint m = minEnd - minStart; + switch (tObj->MinFilter) { + case GL_NEAREST: + for (i = minStart; i < minEnd; i++) + sample_1d_nearest(ctx, tObj, tObj->Image[0][tObj->BaseLevel], + texcoords[i], rgba[i]); + break; + case GL_LINEAR: + for (i = minStart; i < minEnd; i++) + sample_1d_linear(ctx, tObj, tObj->Image[0][tObj->BaseLevel], + texcoords[i], rgba[i]); + break; + case GL_NEAREST_MIPMAP_NEAREST: + sample_1d_nearest_mipmap_nearest(ctx, tObj, m, texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + case GL_LINEAR_MIPMAP_NEAREST: + sample_1d_linear_mipmap_nearest(ctx, tObj, m, texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + case GL_NEAREST_MIPMAP_LINEAR: + sample_1d_nearest_mipmap_linear(ctx, tObj, m, texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + case GL_LINEAR_MIPMAP_LINEAR: + sample_1d_linear_mipmap_linear(ctx, tObj, m, texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + default: + _mesa_problem(ctx, "Bad min filter in sample_1d_texture"); + return; + } + } + + if (magStart < magEnd) { + /* do the magnified texels */ + switch (tObj->MagFilter) { + case GL_NEAREST: + for (i = magStart; i < magEnd; i++) + sample_1d_nearest(ctx, tObj, tObj->Image[0][tObj->BaseLevel], + texcoords[i], rgba[i]); + break; + case GL_LINEAR: + for (i = magStart; i < magEnd; i++) + sample_1d_linear(ctx, tObj, tObj->Image[0][tObj->BaseLevel], + texcoords[i], rgba[i]); + break; + default: + _mesa_problem(ctx, "Bad mag filter in sample_1d_texture"); + return; + } + } +} + + +/**********************************************************************/ +/* 2-D Texture Sampling Functions */ +/**********************************************************************/ + + +/* + * Return the texture sample for coordinate (s,t) using GL_NEAREST filter. + */ +static INLINE void +sample_2d_nearest(GLcontext *ctx, + const struct gl_texture_object *tObj, + const struct gl_texture_image *img, + const GLfloat texcoord[4], + GLchan rgba[]) +{ + const GLint width = img->Width2; /* without border, power of two */ + const GLint height = img->Height2; /* without border, power of two */ + GLint i, j; + (void) ctx; + + COMPUTE_NEAREST_TEXEL_LOCATION(tObj->WrapS, texcoord[0], width, i); + COMPUTE_NEAREST_TEXEL_LOCATION(tObj->WrapT, texcoord[1], height, j); + + /* skip over the border, if any */ + i += img->Border; + j += img->Border; + + if (i < 0 || i >= (GLint) img->Width || j < 0 || j >= (GLint) img->Height) { + /* Need this test for GL_CLAMP_TO_BORDER mode */ + COPY_CHAN4(rgba, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i, j, 0, rgba); + } +} + + + +/** + * Return the texture sample for coordinate (s,t) using GL_LINEAR filter. + * New sampling code contributed by Lynn Quam <quam@ai.sri.com>. + */ +static INLINE void +sample_2d_linear(GLcontext *ctx, + const struct gl_texture_object *tObj, + const struct gl_texture_image *img, + const GLfloat texcoord[4], + GLchan rgba[]) +{ + const GLint width = img->Width2; + const GLint height = img->Height2; + GLint i0, j0, i1, j1; + GLuint useBorderColor; + GLfloat u, v; + (void) ctx; + + COMPUTE_LINEAR_TEXEL_LOCATIONS(tObj->WrapS, texcoord[0], u, width, i0, i1); + COMPUTE_LINEAR_TEXEL_LOCATIONS(tObj->WrapT, texcoord[1], v, height, j0, j1); + + useBorderColor = 0; + if (img->Border) { + i0 += img->Border; + i1 += img->Border; + j0 += img->Border; + j1 += img->Border; + } + else { + if (i0 < 0 || i0 >= width) useBorderColor |= I0BIT; + if (i1 < 0 || i1 >= width) useBorderColor |= I1BIT; + if (j0 < 0 || j0 >= height) useBorderColor |= J0BIT; + if (j1 < 0 || j1 >= height) useBorderColor |= J1BIT; + } + + { + const GLfloat a = FRAC(u); + const GLfloat b = FRAC(v); + GLchan t00[4], t10[4], t01[4], t11[4]; /* sampled texel colors */ + + /* fetch four texel colors */ + if (useBorderColor & (I0BIT | J0BIT)) { + COPY_CHAN4(t00, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i0, j0, 0, t00); + } + if (useBorderColor & (I1BIT | J0BIT)) { + COPY_CHAN4(t10, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i1, j0, 0, t10); + } + if (useBorderColor & (I0BIT | J1BIT)) { + COPY_CHAN4(t01, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i0, j1, 0, t01); + } + if (useBorderColor & (I1BIT | J1BIT)) { + COPY_CHAN4(t11, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i1, j1, 0, t11); + } + + lerp_rgba_2d(rgba, a, b, t00, t10, t01, t11); + } +} + + +/* + * As above, but we know WRAP_S == REPEAT and WRAP_T == REPEAT. + * We don't have to worry about the texture border. + */ +static INLINE void +sample_2d_linear_repeat(GLcontext *ctx, + const struct gl_texture_object *tObj, + const struct gl_texture_image *img, + const GLfloat texcoord[4], + GLchan rgba[]) +{ + const GLint width = img->Width2; + const GLint height = img->Height2; + GLint i0, j0, i1, j1; + GLfloat u, v; + (void) ctx; + (void) tObj; + + ASSERT(tObj->WrapS == GL_REPEAT); + ASSERT(tObj->WrapT == GL_REPEAT); + ASSERT(img->Border == 0); + ASSERT(img->Format != GL_COLOR_INDEX); + ASSERT(img->_IsPowerOfTwo); + + COMPUTE_LINEAR_REPEAT_TEXEL_LOCATION(texcoord[0], u, width, i0, i1); + COMPUTE_LINEAR_REPEAT_TEXEL_LOCATION(texcoord[1], v, height, j0, j1); + + { + const GLfloat a = FRAC(u); + const GLfloat b = FRAC(v); + GLchan t00[4], t10[4], t01[4], t11[4]; /* sampled texel colors */ + + img->FetchTexelc(img, i0, j0, 0, t00); + img->FetchTexelc(img, i1, j0, 0, t10); + img->FetchTexelc(img, i0, j1, 0, t01); + img->FetchTexelc(img, i1, j1, 0, t11); + + lerp_rgba_2d(rgba, a, b, t00, t10, t01, t11); + } +} + + + +static void +sample_2d_nearest_mipmap_nearest(GLcontext *ctx, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + for (i = 0; i < n; i++) { + GLint level; + COMPUTE_NEAREST_MIPMAP_LEVEL(tObj, lambda[i], level); + sample_2d_nearest(ctx, tObj, tObj->Image[0][level], texcoord[i], rgba[i]); + } +} + + + +static void +sample_2d_linear_mipmap_nearest(GLcontext *ctx, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + ASSERT(lambda != NULL); + for (i = 0; i < n; i++) { + GLint level; + COMPUTE_NEAREST_MIPMAP_LEVEL(tObj, lambda[i], level); + sample_2d_linear(ctx, tObj, tObj->Image[0][level], texcoord[i], rgba[i]); + } +} + + + +static void +sample_2d_nearest_mipmap_linear(GLcontext *ctx, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + ASSERT(lambda != NULL); + for (i = 0; i < n; i++) { + GLint level; + COMPUTE_LINEAR_MIPMAP_LEVEL(tObj, lambda[i], level); + if (level >= tObj->_MaxLevel) { + sample_2d_nearest(ctx, tObj, tObj->Image[0][tObj->_MaxLevel], + texcoord[i], rgba[i]); + } + else { + GLchan t0[4], t1[4]; /* texels */ + const GLfloat f = FRAC(lambda[i]); + sample_2d_nearest(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0); + sample_2d_nearest(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1); + lerp_rgba(rgba[i], f, t0, t1); + } + } +} + + + +/* Trilinear filtering */ +static void +sample_2d_linear_mipmap_linear( GLcontext *ctx, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4] ) +{ + GLuint i; + ASSERT(lambda != NULL); + for (i = 0; i < n; i++) { + GLint level; + COMPUTE_LINEAR_MIPMAP_LEVEL(tObj, lambda[i], level); + if (level >= tObj->_MaxLevel) { + sample_2d_linear(ctx, tObj, tObj->Image[0][tObj->_MaxLevel], + texcoord[i], rgba[i]); + } + else { + GLchan t0[4], t1[4]; /* texels */ + const GLfloat f = FRAC(lambda[i]); + sample_2d_linear(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0); + sample_2d_linear(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1); + lerp_rgba(rgba[i], f, t0, t1); + } + } +} + + +static void +sample_2d_linear_mipmap_linear_repeat( GLcontext *ctx, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4] ) +{ + GLuint i; + ASSERT(lambda != NULL); + ASSERT(tObj->WrapS == GL_REPEAT); + ASSERT(tObj->WrapT == GL_REPEAT); + ASSERT(tObj->_IsPowerOfTwo); + for (i = 0; i < n; i++) { + GLint level; + COMPUTE_LINEAR_MIPMAP_LEVEL(tObj, lambda[i], level); + if (level >= tObj->_MaxLevel) { + sample_2d_linear_repeat(ctx, tObj, tObj->Image[0][tObj->_MaxLevel], + texcoord[i], rgba[i]); + } + else { + GLchan t0[4], t1[4]; /* texels */ + const GLfloat f = FRAC(lambda[i]); + sample_2d_linear_repeat(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0); + sample_2d_linear_repeat(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1); + lerp_rgba(rgba[i], f, t0, t1); + } + } +} + + +static void +sample_nearest_2d( GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], + const GLfloat lambda[], GLchan rgba[][4] ) +{ + GLuint i; + struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel]; + (void) texUnit; + (void) lambda; + for (i=0;i<n;i++) { + sample_2d_nearest(ctx, tObj, image, texcoords[i], rgba[i]); + } +} + + + +static void +sample_linear_2d( GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], + const GLfloat lambda[], GLchan rgba[][4] ) +{ + GLuint i; + struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel]; + (void) texUnit; + (void) lambda; + if (tObj->WrapS == GL_REPEAT && tObj->WrapT == GL_REPEAT) { + for (i=0;i<n;i++) { + sample_2d_linear_repeat(ctx, tObj, image, texcoords[i], rgba[i]); + } + } + else { + for (i=0;i<n;i++) { + sample_2d_linear(ctx, tObj, image, texcoords[i], rgba[i]); + } + } +} + + +/* + * Optimized 2-D texture sampling: + * S and T wrap mode == GL_REPEAT + * GL_NEAREST min/mag filter + * No border, + * RowStride == Width, + * Format = GL_RGB + */ +static void +opt_sample_rgb_2d( GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoords[][4], + const GLfloat lambda[], GLchan rgba[][4] ) +{ + const struct gl_texture_image *img = tObj->Image[0][tObj->BaseLevel]; + const GLfloat width = (GLfloat) img->Width; + const GLfloat height = (GLfloat) img->Height; + const GLint colMask = img->Width - 1; + const GLint rowMask = img->Height - 1; + const GLint shift = img->WidthLog2; + GLuint k; + (void) ctx; + (void) texUnit; + (void) lambda; + ASSERT(tObj->WrapS==GL_REPEAT); + ASSERT(tObj->WrapT==GL_REPEAT); + ASSERT(img->Border==0); + ASSERT(img->Format==GL_RGB); + ASSERT(img->_IsPowerOfTwo); + + for (k=0; k<n; k++) { + GLint i = IFLOOR(texcoords[k][0] * width) & colMask; + GLint j = IFLOOR(texcoords[k][1] * height) & rowMask; + GLint pos = (j << shift) | i; + GLchan *texel = ((GLchan *) img->Data) + 3*pos; + rgba[k][RCOMP] = texel[0]; + rgba[k][GCOMP] = texel[1]; + rgba[k][BCOMP] = texel[2]; + } +} + + +/* + * Optimized 2-D texture sampling: + * S and T wrap mode == GL_REPEAT + * GL_NEAREST min/mag filter + * No border + * RowStride == Width, + * Format = GL_RGBA + */ +static void +opt_sample_rgba_2d( GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoords[][4], + const GLfloat lambda[], GLchan rgba[][4] ) +{ + const struct gl_texture_image *img = tObj->Image[0][tObj->BaseLevel]; + const GLfloat width = (GLfloat) img->Width; + const GLfloat height = (GLfloat) img->Height; + const GLint colMask = img->Width - 1; + const GLint rowMask = img->Height - 1; + const GLint shift = img->WidthLog2; + GLuint i; + (void) ctx; + (void) texUnit; + (void) lambda; + ASSERT(tObj->WrapS==GL_REPEAT); + ASSERT(tObj->WrapT==GL_REPEAT); + ASSERT(img->Border==0); + ASSERT(img->Format==GL_RGBA); + ASSERT(img->_IsPowerOfTwo); + + for (i = 0; i < n; i++) { + const GLint col = IFLOOR(texcoords[i][0] * width) & colMask; + const GLint row = IFLOOR(texcoords[i][1] * height) & rowMask; + const GLint pos = (row << shift) | col; + const GLchan *texel = ((GLchan *) img->Data) + (pos << 2); /* pos*4 */ + COPY_CHAN4(rgba[i], texel); + } +} + + +/* + * Given an array of texture coordinate and lambda (level of detail) + * values, return an array of texture sample. + */ +static void +sample_lambda_2d( GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoords[][4], + const GLfloat lambda[], GLchan rgba[][4] ) +{ + const struct gl_texture_image *tImg = tObj->Image[0][tObj->BaseLevel]; + GLuint minStart, minEnd; /* texels with minification */ + GLuint magStart, magEnd; /* texels with magnification */ + + const GLboolean repeatNoBorderPOT = (tObj->WrapS == GL_REPEAT) + && (tObj->WrapT == GL_REPEAT) + && (tImg->Border == 0 && (tImg->Width == tImg->RowStride)) + && (tImg->Format != GL_COLOR_INDEX) + && tImg->_IsPowerOfTwo; + + ASSERT(lambda != NULL); + compute_min_mag_ranges(SWRAST_CONTEXT(ctx)->_MinMagThresh[texUnit], + n, lambda, &minStart, &minEnd, &magStart, &magEnd); + + if (minStart < minEnd) { + /* do the minified texels */ + const GLuint m = minEnd - minStart; + switch (tObj->MinFilter) { + case GL_NEAREST: + if (repeatNoBorderPOT) { + switch (tImg->TexFormat->MesaFormat) { + case MESA_FORMAT_RGB: + case MESA_FORMAT_RGB888: + /*case MESA_FORMAT_BGR888:*/ + opt_sample_rgb_2d(ctx, texUnit, tObj, m, texcoords + minStart, + NULL, rgba + minStart); + break; + case MESA_FORMAT_RGBA: + case MESA_FORMAT_RGBA8888: + case MESA_FORMAT_ARGB8888: + /*case MESA_FORMAT_ABGR8888:*/ + /*case MESA_FORMAT_BGRA8888:*/ + opt_sample_rgba_2d(ctx, texUnit, tObj, m, texcoords + minStart, + NULL, rgba + minStart); + break; + default: + sample_nearest_2d(ctx, texUnit, tObj, m, texcoords + minStart, + NULL, rgba + minStart ); + } + } + else { + sample_nearest_2d(ctx, texUnit, tObj, m, texcoords + minStart, + NULL, rgba + minStart); + } + break; + case GL_LINEAR: + sample_linear_2d(ctx, texUnit, tObj, m, texcoords + minStart, + NULL, rgba + minStart); + break; + case GL_NEAREST_MIPMAP_NEAREST: + sample_2d_nearest_mipmap_nearest(ctx, tObj, m, + texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + case GL_LINEAR_MIPMAP_NEAREST: + sample_2d_linear_mipmap_nearest(ctx, tObj, m, texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + case GL_NEAREST_MIPMAP_LINEAR: + sample_2d_nearest_mipmap_linear(ctx, tObj, m, texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + case GL_LINEAR_MIPMAP_LINEAR: + if (repeatNoBorderPOT) + sample_2d_linear_mipmap_linear_repeat(ctx, tObj, m, + texcoords + minStart, lambda + minStart, rgba + minStart); + else + sample_2d_linear_mipmap_linear(ctx, tObj, m, texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + default: + _mesa_problem(ctx, "Bad min filter in sample_2d_texture"); + return; + } + } + + if (magStart < magEnd) { + /* do the magnified texels */ + const GLuint m = magEnd - magStart; + + switch (tObj->MagFilter) { + case GL_NEAREST: + if (repeatNoBorderPOT) { + switch (tImg->TexFormat->MesaFormat) { + case MESA_FORMAT_RGB: + case MESA_FORMAT_RGB888: + /*case MESA_FORMAT_BGR888:*/ + opt_sample_rgb_2d(ctx, texUnit, tObj, m, texcoords + magStart, + NULL, rgba + magStart); + break; + case MESA_FORMAT_RGBA: + case MESA_FORMAT_RGBA8888: + case MESA_FORMAT_ARGB8888: + /*case MESA_FORMAT_ABGR8888:*/ + /*case MESA_FORMAT_BGRA8888:*/ + opt_sample_rgba_2d(ctx, texUnit, tObj, m, texcoords + magStart, + NULL, rgba + magStart); + break; + default: + sample_nearest_2d(ctx, texUnit, tObj, m, texcoords + magStart, + NULL, rgba + magStart ); + } + } + else { + sample_nearest_2d(ctx, texUnit, tObj, m, texcoords + magStart, + NULL, rgba + magStart); + } + break; + case GL_LINEAR: + sample_linear_2d(ctx, texUnit, tObj, m, texcoords + magStart, + NULL, rgba + magStart); + break; + default: + _mesa_problem(ctx, "Bad mag filter in sample_lambda_2d"); + } + } +} + + + +/**********************************************************************/ +/* 3-D Texture Sampling Functions */ +/**********************************************************************/ + +/* + * Return the texture sample for coordinate (s,t,r) using GL_NEAREST filter. + */ +static void +sample_3d_nearest(GLcontext *ctx, + const struct gl_texture_object *tObj, + const struct gl_texture_image *img, + const GLfloat texcoord[4], + GLchan rgba[4]) +{ + const GLint width = img->Width2; /* without border, power of two */ + const GLint height = img->Height2; /* without border, power of two */ + const GLint depth = img->Depth2; /* without border, power of two */ + GLint i, j, k; + (void) ctx; + + COMPUTE_NEAREST_TEXEL_LOCATION(tObj->WrapS, texcoord[0], width, i); + COMPUTE_NEAREST_TEXEL_LOCATION(tObj->WrapT, texcoord[1], height, j); + COMPUTE_NEAREST_TEXEL_LOCATION(tObj->WrapR, texcoord[2], depth, k); + + if (i < 0 || i >= (GLint) img->Width || + j < 0 || j >= (GLint) img->Height || + k < 0 || k >= (GLint) img->Depth) { + /* Need this test for GL_CLAMP_TO_BORDER mode */ + COPY_CHAN4(rgba, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i, j, k, rgba); + } +} + + + +/* + * Return the texture sample for coordinate (s,t,r) using GL_LINEAR filter. + */ +static void +sample_3d_linear(GLcontext *ctx, + const struct gl_texture_object *tObj, + const struct gl_texture_image *img, + const GLfloat texcoord[4], + GLchan rgba[4]) +{ + const GLint width = img->Width2; + const GLint height = img->Height2; + const GLint depth = img->Depth2; + GLint i0, j0, k0, i1, j1, k1; + GLuint useBorderColor; + GLfloat u, v, w; + (void) ctx; + + COMPUTE_LINEAR_TEXEL_LOCATIONS(tObj->WrapS, texcoord[0], u, width, i0, i1); + COMPUTE_LINEAR_TEXEL_LOCATIONS(tObj->WrapT, texcoord[1], v, height, j0, j1); + COMPUTE_LINEAR_TEXEL_LOCATIONS(tObj->WrapR, texcoord[2], w, depth, k0, k1); + + useBorderColor = 0; + if (img->Border) { + i0 += img->Border; + i1 += img->Border; + j0 += img->Border; + j1 += img->Border; + k0 += img->Border; + k1 += img->Border; + } + else { + /* check if sampling texture border color */ + if (i0 < 0 || i0 >= width) useBorderColor |= I0BIT; + if (i1 < 0 || i1 >= width) useBorderColor |= I1BIT; + if (j0 < 0 || j0 >= height) useBorderColor |= J0BIT; + if (j1 < 0 || j1 >= height) useBorderColor |= J1BIT; + if (k0 < 0 || k0 >= depth) useBorderColor |= K0BIT; + if (k1 < 0 || k1 >= depth) useBorderColor |= K1BIT; + } + + { + const GLfloat a = FRAC(u); + const GLfloat b = FRAC(v); + const GLfloat c = FRAC(w); +#if CHAN_TYPE == GL_UNSIGNED_BYTE + const GLint ia = IROUND_POS(a * ILERP_SCALE); + const GLint ib = IROUND_POS(b * ILERP_SCALE); + const GLint ic = IROUND_POS(c * ILERP_SCALE); +#endif + GLchan t000[4], t010[4], t001[4], t011[4]; + GLchan t100[4], t110[4], t101[4], t111[4]; + + /* Fetch texels */ + if (useBorderColor & (I0BIT | J0BIT | K0BIT)) { + COPY_CHAN4(t000, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i0, j0, k0, t000); + } + if (useBorderColor & (I1BIT | J0BIT | K0BIT)) { + COPY_CHAN4(t100, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i1, j0, k0, t100); + } + if (useBorderColor & (I0BIT | J1BIT | K0BIT)) { + COPY_CHAN4(t010, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i0, j1, k0, t010); + } + if (useBorderColor & (I1BIT | J1BIT | K0BIT)) { + COPY_CHAN4(t110, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i1, j1, k0, t110); + } + + if (useBorderColor & (I0BIT | J0BIT | K1BIT)) { + COPY_CHAN4(t001, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i0, j0, k1, t001); + } + if (useBorderColor & (I1BIT | J0BIT | K1BIT)) { + COPY_CHAN4(t101, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i1, j0, k1, t101); + } + if (useBorderColor & (I0BIT | J1BIT | K1BIT)) { + COPY_CHAN4(t011, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i0, j1, k1, t011); + } + if (useBorderColor & (I1BIT | J1BIT | K1BIT)) { + COPY_CHAN4(t111, tObj->_BorderChan); + } + else { + img->FetchTexelc(img, i1, j1, k1, t111); + } + + /* trilinear interpolation of samples */ +#if CHAN_TYPE == GL_FLOAT + rgba[0] = lerp_3d(a, b, c, + t000[0], t100[0], t010[0], t110[0], + t001[0], t101[0], t011[0], t111[0]); + rgba[1] = lerp_3d(a, b, c, + t000[1], t100[1], t010[1], t110[1], + t001[1], t101[1], t011[1], t111[1]); + rgba[2] = lerp_3d(a, b, c, + t000[2], t100[2], t010[2], t110[2], + t001[2], t101[2], t011[2], t111[2]); + rgba[3] = lerp_3d(a, b, c, + t000[3], t100[3], t010[3], t110[3], + t001[3], t101[3], t011[3], t111[3]); +#elif CHAN_TYPE == GL_UNSIGNED_SHORT + rgba[0] = (GLchan) (lerp_3d(a, b, c, + t000[0], t100[0], t010[0], t110[0], + t001[0], t101[0], t011[0], t111[0]) + 0.5F); + rgba[1] = (GLchan) (lerp_3d(a, b, c, + t000[1], t100[1], t010[1], t110[1], + t001[1], t101[1], t011[1], t111[1]) + 0.5F); + rgba[2] = (GLchan) (lerp_3d(a, b, c, + t000[2], t100[2], t010[2], t110[2], + t001[2], t101[2], t011[2], t111[2]) + 0.5F); + rgba[3] = (GLchan) (lerp_3d(a, b, c, + t000[3], t100[3], t010[3], t110[3], + t001[3], t101[3], t011[3], t111[3]) + 0.5F); +#else + ASSERT(CHAN_TYPE == GL_UNSIGNED_BYTE); + rgba[0] = ilerp_3d(ia, ib, ic, + t000[0], t100[0], t010[0], t110[0], + t001[0], t101[0], t011[0], t111[0]); + rgba[1] = ilerp_3d(ia, ib, ic, + t000[1], t100[1], t010[1], t110[1], + t001[1], t101[1], t011[1], t111[1]); + rgba[2] = ilerp_3d(ia, ib, ic, + t000[2], t100[2], t010[2], t110[2], + t001[2], t101[2], t011[2], t111[2]); + rgba[3] = ilerp_3d(ia, ib, ic, + t000[3], t100[3], t010[3], t110[3], + t001[3], t101[3], t011[3], t111[3]); +#endif + } +} + + + +static void +sample_3d_nearest_mipmap_nearest(GLcontext *ctx, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4] ) +{ + GLuint i; + for (i = 0; i < n; i++) { + GLint level; + COMPUTE_NEAREST_MIPMAP_LEVEL(tObj, lambda[i], level); + sample_3d_nearest(ctx, tObj, tObj->Image[0][level], texcoord[i], rgba[i]); + } +} + + +static void +sample_3d_linear_mipmap_nearest(GLcontext *ctx, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + ASSERT(lambda != NULL); + for (i = 0; i < n; i++) { + GLint level; + COMPUTE_NEAREST_MIPMAP_LEVEL(tObj, lambda[i], level); + sample_3d_linear(ctx, tObj, tObj->Image[0][level], texcoord[i], rgba[i]); + } +} + + +static void +sample_3d_nearest_mipmap_linear(GLcontext *ctx, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + ASSERT(lambda != NULL); + for (i = 0; i < n; i++) { + GLint level; + COMPUTE_LINEAR_MIPMAP_LEVEL(tObj, lambda[i], level); + if (level >= tObj->_MaxLevel) { + sample_3d_nearest(ctx, tObj, tObj->Image[0][tObj->_MaxLevel], + texcoord[i], rgba[i]); + } + else { + GLchan t0[4], t1[4]; /* texels */ + const GLfloat f = FRAC(lambda[i]); + sample_3d_nearest(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0); + sample_3d_nearest(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1); + lerp_rgba(rgba[i], f, t0, t1); + } + } +} + + +static void +sample_3d_linear_mipmap_linear(GLcontext *ctx, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + ASSERT(lambda != NULL); + for (i = 0; i < n; i++) { + GLint level; + COMPUTE_LINEAR_MIPMAP_LEVEL(tObj, lambda[i], level); + if (level >= tObj->_MaxLevel) { + sample_3d_linear(ctx, tObj, tObj->Image[0][tObj->_MaxLevel], + texcoord[i], rgba[i]); + } + else { + GLchan t0[4], t1[4]; /* texels */ + const GLfloat f = FRAC(lambda[i]); + sample_3d_linear(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0); + sample_3d_linear(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1); + lerp_rgba(rgba[i], f, t0, t1); + } + } +} + + +static void +sample_nearest_3d(GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], const GLfloat lambda[], + GLchan rgba[][4]) +{ + GLuint i; + struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel]; + (void) texUnit; + (void) lambda; + for (i=0;i<n;i++) { + sample_3d_nearest(ctx, tObj, image, texcoords[i], rgba[i]); + } +} + + + +static void +sample_linear_3d( GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], + const GLfloat lambda[], GLchan rgba[][4] ) +{ + GLuint i; + struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel]; + (void) texUnit; + (void) lambda; + for (i=0;i<n;i++) { + sample_3d_linear(ctx, tObj, image, texcoords[i], rgba[i]); + } +} + + +/* + * Given an (s,t,r) texture coordinate and lambda (level of detail) value, + * return a texture sample. + */ +static void +sample_lambda_3d( GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], const GLfloat lambda[], + GLchan rgba[][4] ) +{ + GLuint minStart, minEnd; /* texels with minification */ + GLuint magStart, magEnd; /* texels with magnification */ + GLuint i; + + ASSERT(lambda != NULL); + compute_min_mag_ranges(SWRAST_CONTEXT(ctx)->_MinMagThresh[texUnit], + n, lambda, &minStart, &minEnd, &magStart, &magEnd); + + if (minStart < minEnd) { + /* do the minified texels */ + GLuint m = minEnd - minStart; + switch (tObj->MinFilter) { + case GL_NEAREST: + for (i = minStart; i < minEnd; i++) + sample_3d_nearest(ctx, tObj, tObj->Image[0][tObj->BaseLevel], + texcoords[i], rgba[i]); + break; + case GL_LINEAR: + for (i = minStart; i < minEnd; i++) + sample_3d_linear(ctx, tObj, tObj->Image[0][tObj->BaseLevel], + texcoords[i], rgba[i]); + break; + case GL_NEAREST_MIPMAP_NEAREST: + sample_3d_nearest_mipmap_nearest(ctx, tObj, m, texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + case GL_LINEAR_MIPMAP_NEAREST: + sample_3d_linear_mipmap_nearest(ctx, tObj, m, texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + case GL_NEAREST_MIPMAP_LINEAR: + sample_3d_nearest_mipmap_linear(ctx, tObj, m, texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + case GL_LINEAR_MIPMAP_LINEAR: + sample_3d_linear_mipmap_linear(ctx, tObj, m, texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + default: + _mesa_problem(ctx, "Bad min filter in sample_3d_texture"); + return; + } + } + + if (magStart < magEnd) { + /* do the magnified texels */ + switch (tObj->MagFilter) { + case GL_NEAREST: + for (i = magStart; i < magEnd; i++) + sample_3d_nearest(ctx, tObj, tObj->Image[0][tObj->BaseLevel], + texcoords[i], rgba[i]); + break; + case GL_LINEAR: + for (i = magStart; i < magEnd; i++) + sample_3d_linear(ctx, tObj, tObj->Image[0][tObj->BaseLevel], + texcoords[i], rgba[i]); + break; + default: + _mesa_problem(ctx, "Bad mag filter in sample_3d_texture"); + return; + } + } +} + + +/**********************************************************************/ +/* Texture Cube Map Sampling Functions */ +/**********************************************************************/ + +/** + * Choose one of six sides of a texture cube map given the texture + * coord (rx,ry,rz). Return pointer to corresponding array of texture + * images. + */ +static const struct gl_texture_image ** +choose_cube_face(const struct gl_texture_object *texObj, + const GLfloat texcoord[4], GLfloat newCoord[4]) +{ + /* + major axis + direction target sc tc ma + ---------- ------------------------------- --- --- --- + +rx TEXTURE_CUBE_MAP_POSITIVE_X_EXT -rz -ry rx + -rx TEXTURE_CUBE_MAP_NEGATIVE_X_EXT +rz -ry rx + +ry TEXTURE_CUBE_MAP_POSITIVE_Y_EXT +rx +rz ry + -ry TEXTURE_CUBE_MAP_NEGATIVE_Y_EXT +rx -rz ry + +rz TEXTURE_CUBE_MAP_POSITIVE_Z_EXT +rx -ry rz + -rz TEXTURE_CUBE_MAP_NEGATIVE_Z_EXT -rx -ry rz + */ + const GLfloat rx = texcoord[0]; + const GLfloat ry = texcoord[1]; + const GLfloat rz = texcoord[2]; + const GLfloat arx = FABSF(rx), ary = FABSF(ry), arz = FABSF(rz); + GLuint face; + GLfloat sc, tc, ma; + + if (arx > ary && arx > arz) { + if (rx >= 0.0F) { + face = FACE_POS_X; + sc = -rz; + tc = -ry; + ma = arx; + } + else { + face = FACE_NEG_X; + sc = rz; + tc = -ry; + ma = arx; + } + } + else if (ary > arx && ary > arz) { + if (ry >= 0.0F) { + face = FACE_POS_Y; + sc = rx; + tc = rz; + ma = ary; + } + else { + face = FACE_NEG_Y; + sc = rx; + tc = -rz; + ma = ary; + } + } + else { + if (rz > 0.0F) { + face = FACE_POS_Z; + sc = rx; + tc = -ry; + ma = arz; + } + else { + face = FACE_NEG_Z; + sc = -rx; + tc = -ry; + ma = arz; + } + } + + newCoord[0] = ( sc / ma + 1.0F ) * 0.5F; + newCoord[1] = ( tc / ma + 1.0F ) * 0.5F; + return (const struct gl_texture_image **) texObj->Image[face]; +} + + +static void +sample_nearest_cube(GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], const GLfloat lambda[], + GLchan rgba[][4]) +{ + GLuint i; + (void) texUnit; + (void) lambda; + for (i = 0; i < n; i++) { + const struct gl_texture_image **images; + GLfloat newCoord[4]; + images = choose_cube_face(tObj, texcoords[i], newCoord); + sample_2d_nearest(ctx, tObj, images[tObj->BaseLevel], + newCoord, rgba[i]); + } +} + + +static void +sample_linear_cube(GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + (void) texUnit; + (void) lambda; + for (i = 0; i < n; i++) { + const struct gl_texture_image **images; + GLfloat newCoord[4]; + images = choose_cube_face(tObj, texcoords[i], newCoord); + sample_2d_linear(ctx, tObj, images[tObj->BaseLevel], + newCoord, rgba[i]); + } +} + + +static void +sample_cube_nearest_mipmap_nearest(GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + (void) texUnit; + ASSERT(lambda != NULL); + for (i = 0; i < n; i++) { + const struct gl_texture_image **images; + GLfloat newCoord[4]; + GLint level; + COMPUTE_NEAREST_MIPMAP_LEVEL(tObj, lambda[i], level); + images = choose_cube_face(tObj, texcoord[i], newCoord); + sample_2d_nearest(ctx, tObj, images[level], newCoord, rgba[i]); + } +} + + +static void +sample_cube_linear_mipmap_nearest(GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + (void) texUnit; + ASSERT(lambda != NULL); + for (i = 0; i < n; i++) { + const struct gl_texture_image **images; + GLfloat newCoord[4]; + GLint level; + COMPUTE_NEAREST_MIPMAP_LEVEL(tObj, lambda[i], level); + images = choose_cube_face(tObj, texcoord[i], newCoord); + sample_2d_linear(ctx, tObj, images[level], newCoord, rgba[i]); + } +} + + +static void +sample_cube_nearest_mipmap_linear(GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + (void) texUnit; + ASSERT(lambda != NULL); + for (i = 0; i < n; i++) { + const struct gl_texture_image **images; + GLfloat newCoord[4]; + GLint level; + COMPUTE_LINEAR_MIPMAP_LEVEL(tObj, lambda[i], level); + images = choose_cube_face(tObj, texcoord[i], newCoord); + if (level >= tObj->_MaxLevel) { + sample_2d_nearest(ctx, tObj, images[tObj->_MaxLevel], + newCoord, rgba[i]); + } + else { + GLchan t0[4], t1[4]; /* texels */ + const GLfloat f = FRAC(lambda[i]); + sample_2d_nearest(ctx, tObj, images[level ], newCoord, t0); + sample_2d_nearest(ctx, tObj, images[level+1], newCoord, t1); + lerp_rgba(rgba[i], f, t0, t1); + } + } +} + + +static void +sample_cube_linear_mipmap_linear(GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, + GLuint n, const GLfloat texcoord[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + GLuint i; + (void) texUnit; + ASSERT(lambda != NULL); + for (i = 0; i < n; i++) { + const struct gl_texture_image **images; + GLfloat newCoord[4]; + GLint level; + COMPUTE_LINEAR_MIPMAP_LEVEL(tObj, lambda[i], level); + images = choose_cube_face(tObj, texcoord[i], newCoord); + if (level >= tObj->_MaxLevel) { + sample_2d_linear(ctx, tObj, images[tObj->_MaxLevel], + newCoord, rgba[i]); + } + else { + GLchan t0[4], t1[4]; + const GLfloat f = FRAC(lambda[i]); + sample_2d_linear(ctx, tObj, images[level ], newCoord, t0); + sample_2d_linear(ctx, tObj, images[level+1], newCoord, t1); + lerp_rgba(rgba[i], f, t0, t1); + } + } +} + + +static void +sample_lambda_cube( GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], const GLfloat lambda[], + GLchan rgba[][4]) +{ + GLuint minStart, minEnd; /* texels with minification */ + GLuint magStart, magEnd; /* texels with magnification */ + + ASSERT(lambda != NULL); + compute_min_mag_ranges(SWRAST_CONTEXT(ctx)->_MinMagThresh[texUnit], + n, lambda, &minStart, &minEnd, &magStart, &magEnd); + + if (minStart < minEnd) { + /* do the minified texels */ + const GLuint m = minEnd - minStart; + switch (tObj->MinFilter) { + case GL_NEAREST: + sample_nearest_cube(ctx, texUnit, tObj, m, texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + case GL_LINEAR: + sample_linear_cube(ctx, texUnit, tObj, m, texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + case GL_NEAREST_MIPMAP_NEAREST: + sample_cube_nearest_mipmap_nearest(ctx, texUnit, tObj, m, + texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + case GL_LINEAR_MIPMAP_NEAREST: + sample_cube_linear_mipmap_nearest(ctx, texUnit, tObj, m, + texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + case GL_NEAREST_MIPMAP_LINEAR: + sample_cube_nearest_mipmap_linear(ctx, texUnit, tObj, m, + texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + case GL_LINEAR_MIPMAP_LINEAR: + sample_cube_linear_mipmap_linear(ctx, texUnit, tObj, m, + texcoords + minStart, + lambda + minStart, rgba + minStart); + break; + default: + _mesa_problem(ctx, "Bad min filter in sample_lambda_cube"); + } + } + + if (magStart < magEnd) { + /* do the magnified texels */ + const GLuint m = magEnd - magStart; + switch (tObj->MagFilter) { + case GL_NEAREST: + sample_nearest_cube(ctx, texUnit, tObj, m, texcoords + magStart, + lambda + magStart, rgba + magStart); + break; + case GL_LINEAR: + sample_linear_cube(ctx, texUnit, tObj, m, texcoords + magStart, + lambda + magStart, rgba + magStart); + break; + default: + _mesa_problem(ctx, "Bad mag filter in sample_lambda_cube"); + } + } +} + + +/**********************************************************************/ +/* Texture Rectangle Sampling Functions */ +/**********************************************************************/ + +static void +sample_nearest_rect(GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], const GLfloat lambda[], + GLchan rgba[][4]) +{ + const struct gl_texture_image *img = tObj->Image[0][0]; + const GLfloat width = (GLfloat) img->Width; + const GLfloat height = (GLfloat) img->Height; + const GLint width_minus_1 = img->Width - 1; + const GLint height_minus_1 = img->Height - 1; + GLuint i; + + (void) ctx; + (void) texUnit; + (void) lambda; + + ASSERT(tObj->WrapS == GL_CLAMP || + tObj->WrapS == GL_CLAMP_TO_EDGE || + tObj->WrapS == GL_CLAMP_TO_BORDER); + ASSERT(tObj->WrapT == GL_CLAMP || + tObj->WrapT == GL_CLAMP_TO_EDGE || + tObj->WrapT == GL_CLAMP_TO_BORDER); + ASSERT(img->Format != GL_COLOR_INDEX); + + /* XXX move Wrap mode tests outside of loops for common cases */ + for (i = 0; i < n; i++) { + GLint row, col; + /* NOTE: we DO NOT use [0, 1] texture coordinates! */ + if (tObj->WrapS == GL_CLAMP) { + col = IFLOOR( CLAMP(texcoords[i][0], 0.0F, width - 1) ); + } + else if (tObj->WrapS == GL_CLAMP_TO_EDGE) { + col = IFLOOR( CLAMP(texcoords[i][0], 0.5F, width - 0.5F) ); + } + else { + col = IFLOOR( CLAMP(texcoords[i][0], -0.5F, width + 0.5F) ); + } + if (tObj->WrapT == GL_CLAMP) { + row = IFLOOR( CLAMP(texcoords[i][1], 0.0F, height - 1) ); + } + else if (tObj->WrapT == GL_CLAMP_TO_EDGE) { + row = IFLOOR( CLAMP(texcoords[i][1], 0.5F, height - 0.5F) ); + } + else { + row = IFLOOR( CLAMP(texcoords[i][1], -0.5F, height + 0.5F) ); + } + + if (col < 0 || col > width_minus_1 || row < 0 || row > height_minus_1) + COPY_CHAN4(rgba[i], tObj->_BorderChan); + else + img->FetchTexelc(img, col, row, 0, rgba[i]); + } +} + + +static void +sample_linear_rect(GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], + const GLfloat lambda[], GLchan rgba[][4]) +{ + const struct gl_texture_image *img = tObj->Image[0][0]; + const GLfloat width = (GLfloat) img->Width; + const GLfloat height = (GLfloat) img->Height; + const GLint width_minus_1 = img->Width - 1; + const GLint height_minus_1 = img->Height - 1; + GLuint i; + + (void) ctx; + (void) texUnit; + (void) lambda; + + ASSERT(tObj->WrapS == GL_CLAMP || + tObj->WrapS == GL_CLAMP_TO_EDGE || + tObj->WrapS == GL_CLAMP_TO_BORDER); + ASSERT(tObj->WrapT == GL_CLAMP || + tObj->WrapT == GL_CLAMP_TO_EDGE || + tObj->WrapT == GL_CLAMP_TO_BORDER); + ASSERT(img->Format != GL_COLOR_INDEX); + + /* XXX lots of opportunity for optimization in this loop */ + for (i = 0; i < n; i++) { + GLfloat frow, fcol; + GLint i0, j0, i1, j1; + GLchan t00[4], t01[4], t10[4], t11[4]; + GLfloat a, b; + GLuint useBorderColor = 0; + + /* NOTE: we DO NOT use [0, 1] texture coordinates! */ + if (tObj->WrapS == GL_CLAMP) { + /* Not exactly what the spec says, but it matches NVIDIA output */ + fcol = CLAMP(texcoords[i][0] - 0.5F, 0.0, width_minus_1); + i0 = IFLOOR(fcol); + i1 = i0 + 1; + } + else if (tObj->WrapS == GL_CLAMP_TO_EDGE) { + fcol = CLAMP(texcoords[i][0], 0.5F, width - 0.5F); + fcol -= 0.5F; + i0 = IFLOOR(fcol); + i1 = i0 + 1; + if (i1 > width_minus_1) + i1 = width_minus_1; + } + else { + ASSERT(tObj->WrapS == GL_CLAMP_TO_BORDER); + fcol = CLAMP(texcoords[i][0], -0.5F, width + 0.5F); + fcol -= 0.5F; + i0 = IFLOOR(fcol); + i1 = i0 + 1; + } + + if (tObj->WrapT == GL_CLAMP) { + /* Not exactly what the spec says, but it matches NVIDIA output */ + frow = CLAMP(texcoords[i][1] - 0.5F, 0.0, width_minus_1); + j0 = IFLOOR(frow); + j1 = j0 + 1; + } + else if (tObj->WrapT == GL_CLAMP_TO_EDGE) { + frow = CLAMP(texcoords[i][1], 0.5F, height - 0.5F); + frow -= 0.5F; + j0 = IFLOOR(frow); + j1 = j0 + 1; + if (j1 > height_minus_1) + j1 = height_minus_1; + } + else { + ASSERT(tObj->WrapT == GL_CLAMP_TO_BORDER); + frow = CLAMP(texcoords[i][1], -0.5F, height + 0.5F); + frow -= 0.5F; + j0 = IFLOOR(frow); + j1 = j0 + 1; + } + + /* compute integer rows/columns */ + if (i0 < 0 || i0 > width_minus_1) useBorderColor |= I0BIT; + if (i1 < 0 || i1 > width_minus_1) useBorderColor |= I1BIT; + if (j0 < 0 || j0 > height_minus_1) useBorderColor |= J0BIT; + if (j1 < 0 || j1 > height_minus_1) useBorderColor |= J1BIT; + + /* get four texel samples */ + if (useBorderColor & (I0BIT | J0BIT)) + COPY_CHAN4(t00, tObj->_BorderChan); + else + img->FetchTexelc(img, i0, j0, 0, t00); + + if (useBorderColor & (I1BIT | J0BIT)) + COPY_CHAN4(t10, tObj->_BorderChan); + else + img->FetchTexelc(img, i1, j0, 0, t10); + + if (useBorderColor & (I0BIT | J1BIT)) + COPY_CHAN4(t01, tObj->_BorderChan); + else + img->FetchTexelc(img, i0, j1, 0, t01); + + if (useBorderColor & (I1BIT | J1BIT)) + COPY_CHAN4(t11, tObj->_BorderChan); + else + img->FetchTexelc(img, i1, j1, 0, t11); + + /* compute interpolants */ + a = FRAC(fcol); + b = FRAC(frow); + + lerp_rgba_2d(rgba[i], a, b, t00, t10, t01, t11); + } +} + + +static void +sample_lambda_rect( GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], const GLfloat lambda[], + GLchan rgba[][4]) +{ + GLuint minStart, minEnd, magStart, magEnd; + + /* We only need lambda to decide between minification and magnification. + * There is no mipmapping with rectangular textures. + */ + compute_min_mag_ranges(SWRAST_CONTEXT(ctx)->_MinMagThresh[texUnit], + n, lambda, &minStart, &minEnd, &magStart, &magEnd); + + if (minStart < minEnd) { + if (tObj->MinFilter == GL_NEAREST) { + sample_nearest_rect( ctx, texUnit, tObj, minEnd - minStart, + texcoords + minStart, NULL, rgba + minStart); + } + else { + sample_linear_rect( ctx, texUnit, tObj, minEnd - minStart, + texcoords + minStart, NULL, rgba + minStart); + } + } + if (magStart < magEnd) { + if (tObj->MagFilter == GL_NEAREST) { + sample_nearest_rect( ctx, texUnit, tObj, magEnd - magStart, + texcoords + magStart, NULL, rgba + magStart); + } + else { + sample_linear_rect( ctx, texUnit, tObj, magEnd - magStart, + texcoords + magStart, NULL, rgba + magStart); + } + } +} + + + +/* + * Sample a shadow/depth texture. + */ +static void +sample_depth_texture( GLcontext *ctx, GLuint unit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], const GLfloat lambda[], + GLchan texel[][4] ) +{ + const GLint baseLevel = tObj->BaseLevel; + const struct gl_texture_image *texImage = tObj->Image[0][baseLevel]; + const GLuint width = texImage->Width; + const GLuint height = texImage->Height; + GLchan ambient; + GLenum function; + GLchan result; + + (void) lambda; + (void) unit; + + ASSERT(tObj->Image[0][tObj->BaseLevel]->Format == GL_DEPTH_COMPONENT); + ASSERT(tObj->Target == GL_TEXTURE_1D || + tObj->Target == GL_TEXTURE_2D || + tObj->Target == GL_TEXTURE_RECTANGLE_NV); + + UNCLAMPED_FLOAT_TO_CHAN(ambient, tObj->ShadowAmbient); + + /* XXXX if tObj->MinFilter != tObj->MagFilter, we're ignoring lambda */ + + /* XXX this could be precomputed and saved in the texture object */ + if (tObj->CompareFlag) { + /* GL_SGIX_shadow */ + if (tObj->CompareOperator == GL_TEXTURE_LEQUAL_R_SGIX) { + function = GL_LEQUAL; + } + else { + ASSERT(tObj->CompareOperator == GL_TEXTURE_GEQUAL_R_SGIX); + function = GL_GEQUAL; + } + } + else if (tObj->CompareMode == GL_COMPARE_R_TO_TEXTURE_ARB) { + /* GL_ARB_shadow */ + function = tObj->CompareFunc; + } + else { + function = GL_NONE; /* pass depth through as grayscale */ + } + + if (tObj->MagFilter == GL_NEAREST) { + GLuint i; + for (i = 0; i < n; i++) { + GLfloat depthSample; + GLint col, row; + /* XXX fix for texture rectangle! */ + COMPUTE_NEAREST_TEXEL_LOCATION(tObj->WrapS, texcoords[i][0], width, col); + COMPUTE_NEAREST_TEXEL_LOCATION(tObj->WrapT, texcoords[i][1], height, row); + texImage->FetchTexelf(texImage, col, row, 0, &depthSample); + + switch (function) { + case GL_LEQUAL: + result = (texcoords[i][2] <= depthSample) ? CHAN_MAX : ambient; + break; + case GL_GEQUAL: + result = (texcoords[i][2] >= depthSample) ? CHAN_MAX : ambient; + break; + case GL_LESS: + result = (texcoords[i][2] < depthSample) ? CHAN_MAX : ambient; + break; + case GL_GREATER: + result = (texcoords[i][2] > depthSample) ? CHAN_MAX : ambient; + break; + case GL_EQUAL: + result = (texcoords[i][2] == depthSample) ? CHAN_MAX : ambient; + break; + case GL_NOTEQUAL: + result = (texcoords[i][2] != depthSample) ? CHAN_MAX : ambient; + break; + case GL_ALWAYS: + result = CHAN_MAX; + break; + case GL_NEVER: + result = ambient; + break; + case GL_NONE: + CLAMPED_FLOAT_TO_CHAN(result, depthSample); + break; + default: + _mesa_problem(ctx, "Bad compare func in sample_depth_texture"); + return; + } + + switch (tObj->DepthMode) { + case GL_LUMINANCE: + texel[i][RCOMP] = result; + texel[i][GCOMP] = result; + texel[i][BCOMP] = result; + texel[i][ACOMP] = CHAN_MAX; + break; + case GL_INTENSITY: + texel[i][RCOMP] = result; + texel[i][GCOMP] = result; + texel[i][BCOMP] = result; + texel[i][ACOMP] = result; + break; + case GL_ALPHA: + texel[i][RCOMP] = 0; + texel[i][GCOMP] = 0; + texel[i][BCOMP] = 0; + texel[i][ACOMP] = result; + break; + default: + _mesa_problem(ctx, "Bad depth texture mode"); + } + } + } + else { + GLuint i; + ASSERT(tObj->MagFilter == GL_LINEAR); + for (i = 0; i < n; i++) { + GLfloat depth00, depth01, depth10, depth11; + GLint i0, i1, j0, j1; + GLfloat u, v; + GLuint useBorderTexel; + + /* XXX fix for texture rectangle! */ + COMPUTE_LINEAR_TEXEL_LOCATIONS(tObj->WrapS, texcoords[i][0], u, width, i0, i1); + COMPUTE_LINEAR_TEXEL_LOCATIONS(tObj->WrapT, texcoords[i][1], v, height,j0, j1); + + useBorderTexel = 0; + if (texImage->Border) { + i0 += texImage->Border; + i1 += texImage->Border; + j0 += texImage->Border; + j1 += texImage->Border; + } + else { + if (i0 < 0 || i0 >= (GLint) width) useBorderTexel |= I0BIT; + if (i1 < 0 || i1 >= (GLint) width) useBorderTexel |= I1BIT; + if (j0 < 0 || j0 >= (GLint) height) useBorderTexel |= J0BIT; + if (j1 < 0 || j1 >= (GLint) height) useBorderTexel |= J1BIT; + } + + /* get four depth samples from the texture */ + if (useBorderTexel & (I0BIT | J0BIT)) { + depth00 = 1.0; + } + else { + texImage->FetchTexelf(texImage, i0, j0, 0, &depth00); + } + if (useBorderTexel & (I1BIT | J0BIT)) { + depth10 = 1.0; + } + else { + texImage->FetchTexelf(texImage, i1, j0, 0, &depth10); + } + if (useBorderTexel & (I0BIT | J1BIT)) { + depth01 = 1.0; + } + else { + texImage->FetchTexelf(texImage, i0, j1, 0, &depth01); + } + if (useBorderTexel & (I1BIT | J1BIT)) { + depth11 = 1.0; + } + else { + texImage->FetchTexelf(texImage, i1, j1, 0, &depth11); + } + + if (0) { + /* compute a single weighted depth sample and do one comparison */ + const GLfloat a = FRAC(u + 1.0F); + const GLfloat b = FRAC(v + 1.0F); + const GLfloat depthSample + = lerp_2d(a, b, depth00, depth10, depth01, depth11); + if ((depthSample <= texcoords[i][2] && function == GL_LEQUAL) || + (depthSample >= texcoords[i][2] && function == GL_GEQUAL)) { + result = ambient; + } + else { + result = CHAN_MAX; + } + } + else { + /* Do four depth/R comparisons and compute a weighted result. + * If this touches on somebody's I.P., I'll remove this code + * upon request. + */ + const GLfloat d = (CHAN_MAXF - (GLfloat) ambient) * 0.25F; + GLfloat luminance = CHAN_MAXF; + + switch (function) { + case GL_LEQUAL: + if (depth00 <= texcoords[i][2]) luminance -= d; + if (depth01 <= texcoords[i][2]) luminance -= d; + if (depth10 <= texcoords[i][2]) luminance -= d; + if (depth11 <= texcoords[i][2]) luminance -= d; + result = (GLchan) luminance; + break; + case GL_GEQUAL: + if (depth00 >= texcoords[i][2]) luminance -= d; + if (depth01 >= texcoords[i][2]) luminance -= d; + if (depth10 >= texcoords[i][2]) luminance -= d; + if (depth11 >= texcoords[i][2]) luminance -= d; + result = (GLchan) luminance; + break; + case GL_LESS: + if (depth00 < texcoords[i][2]) luminance -= d; + if (depth01 < texcoords[i][2]) luminance -= d; + if (depth10 < texcoords[i][2]) luminance -= d; + if (depth11 < texcoords[i][2]) luminance -= d; + result = (GLchan) luminance; + break; + case GL_GREATER: + if (depth00 > texcoords[i][2]) luminance -= d; + if (depth01 > texcoords[i][2]) luminance -= d; + if (depth10 > texcoords[i][2]) luminance -= d; + if (depth11 > texcoords[i][2]) luminance -= d; + result = (GLchan) luminance; + break; + case GL_EQUAL: + if (depth00 == texcoords[i][2]) luminance -= d; + if (depth01 == texcoords[i][2]) luminance -= d; + if (depth10 == texcoords[i][2]) luminance -= d; + if (depth11 == texcoords[i][2]) luminance -= d; + result = (GLchan) luminance; + break; + case GL_NOTEQUAL: + if (depth00 != texcoords[i][2]) luminance -= d; + if (depth01 != texcoords[i][2]) luminance -= d; + if (depth10 != texcoords[i][2]) luminance -= d; + if (depth11 != texcoords[i][2]) luminance -= d; + result = (GLchan) luminance; + break; + case GL_ALWAYS: + result = 0; + break; + case GL_NEVER: + result = CHAN_MAX; + break; + case GL_NONE: + /* ordinary bilinear filtering */ + { + const GLfloat a = FRAC(u + 1.0F); + const GLfloat b = FRAC(v + 1.0F); + const GLfloat depthSample + = lerp_2d(a, b, depth00, depth10, depth01, depth11); + CLAMPED_FLOAT_TO_CHAN(result, depthSample); + } + break; + default: + _mesa_problem(ctx, "Bad compare func in sample_depth_texture"); + return; + } + } + + switch (tObj->DepthMode) { + case GL_LUMINANCE: + texel[i][RCOMP] = result; + texel[i][GCOMP] = result; + texel[i][BCOMP] = result; + texel[i][ACOMP] = CHAN_MAX; + break; + case GL_INTENSITY: + texel[i][RCOMP] = result; + texel[i][GCOMP] = result; + texel[i][BCOMP] = result; + texel[i][ACOMP] = result; + break; + case GL_ALPHA: + texel[i][RCOMP] = 0; + texel[i][GCOMP] = 0; + texel[i][BCOMP] = 0; + texel[i][ACOMP] = result; + break; + default: + _mesa_problem(ctx, "Bad depth texture mode"); + } + } /* for */ + } /* if filter */ +} + + +#if 0 +/* + * Experimental depth texture sampling function. + */ +static void +sample_depth_texture2(const GLcontext *ctx, + const struct gl_texture_unit *texUnit, + GLuint n, const GLfloat texcoords[][4], + GLchan texel[][4]) +{ + const struct gl_texture_object *texObj = texUnit->_Current; + const GLint baseLevel = texObj->BaseLevel; + const struct gl_texture_image *texImage = texObj->Image[0][baseLevel]; + const GLuint width = texImage->Width; + const GLuint height = texImage->Height; + GLchan ambient; + GLboolean lequal, gequal; + + if (texObj->Target != GL_TEXTURE_2D) { + _mesa_problem(ctx, "only 2-D depth textures supported at this time"); + return; + } + + if (texObj->MinFilter != texObj->MagFilter) { + _mesa_problem(ctx, "mipmapped depth textures not supported at this time"); + return; + } + + /* XXX the GL_SGIX_shadow extension spec doesn't say what to do if + * GL_TEXTURE_COMPARE_SGIX == GL_TRUE but the current texture object + * isn't a depth texture. + */ + if (texImage->Format != GL_DEPTH_COMPONENT) { + _mesa_problem(ctx,"GL_TEXTURE_COMPARE_SGIX enabled with non-depth texture"); + return; + } + + UNCLAMPED_FLOAT_TO_CHAN(ambient, tObj->ShadowAmbient); + + if (texObj->CompareOperator == GL_TEXTURE_LEQUAL_R_SGIX) { + lequal = GL_TRUE; + gequal = GL_FALSE; + } + else { + lequal = GL_FALSE; + gequal = GL_TRUE; + } + + { + GLuint i; + for (i = 0; i < n; i++) { + const GLint K = 3; + GLint col, row, ii, jj, imin, imax, jmin, jmax, samples, count; + GLfloat w; + GLchan lum; + COMPUTE_NEAREST_TEXEL_LOCATION(texObj->WrapS, texcoords[i][0], + width, col); + COMPUTE_NEAREST_TEXEL_LOCATION(texObj->WrapT, texcoords[i][1], + height, row); + + imin = col - K; + imax = col + K; + jmin = row - K; + jmax = row + K; + + if (imin < 0) imin = 0; + if (imax >= width) imax = width - 1; + if (jmin < 0) jmin = 0; + if (jmax >= height) jmax = height - 1; + + samples = (imax - imin + 1) * (jmax - jmin + 1); + count = 0; + for (jj = jmin; jj <= jmax; jj++) { + for (ii = imin; ii <= imax; ii++) { + GLfloat depthSample; + texImage->FetchTexelf(texImage, ii, jj, 0, &depthSample); + if ((depthSample <= r[i] && lequal) || + (depthSample >= r[i] && gequal)) { + count++; + } + } + } + + w = (GLfloat) count / (GLfloat) samples; + w = CHAN_MAXF - w * (CHAN_MAXF - (GLfloat) ambient); + lum = (GLint) w; + + texel[i][RCOMP] = lum; + texel[i][GCOMP] = lum; + texel[i][BCOMP] = lum; + texel[i][ACOMP] = CHAN_MAX; + } + } +} +#endif + + +/** + * We use this function when a texture object is in an "incomplete" state. + * When a fragment program attempts to sample an incomplete texture we + * return black (see issue 23 in GL_ARB_fragment_program spec). + * Note: fragment programss don't observe the texture enable/disable flags. + */ +static void +null_sample_func( GLcontext *ctx, GLuint texUnit, + const struct gl_texture_object *tObj, GLuint n, + const GLfloat texcoords[][4], const GLfloat lambda[], + GLchan rgba[][4]) +{ + GLuint i; + (void) ctx; + (void) texUnit; + (void) tObj; + (void) texcoords; + (void) lambda; + for (i = 0; i < n; i++) { + rgba[i][RCOMP] = 0; + rgba[i][GCOMP] = 0; + rgba[i][BCOMP] = 0; + rgba[i][ACOMP] = CHAN_MAX; + } +} + + +/** + * Choose the texture sampling function for the given texture object. + */ +texture_sample_func +_swrast_choose_texture_sample_func( GLcontext *ctx, + const struct gl_texture_object *t ) +{ + if (!t || !t->Complete) { + return &null_sample_func; + } + else { + const GLboolean needLambda = (GLboolean) (t->MinFilter != t->MagFilter); + const GLenum format = t->Image[0][t->BaseLevel]->Format; + + switch (t->Target) { + case GL_TEXTURE_1D: + if (format == GL_DEPTH_COMPONENT) { + return &sample_depth_texture; + } + else if (needLambda) { + return &sample_lambda_1d; + } + else if (t->MinFilter == GL_LINEAR) { + return &sample_linear_1d; + } + else { + ASSERT(t->MinFilter == GL_NEAREST); + return &sample_nearest_1d; + } + case GL_TEXTURE_2D: + if (format == GL_DEPTH_COMPONENT) { + return &sample_depth_texture; + } + else if (needLambda) { + return &sample_lambda_2d; + } + else if (t->MinFilter == GL_LINEAR) { + return &sample_linear_2d; + } + else { + GLint baseLevel = t->BaseLevel; + ASSERT(t->MinFilter == GL_NEAREST); + if (t->WrapS == GL_REPEAT && + t->WrapT == GL_REPEAT && + t->_IsPowerOfTwo && + t->Image[0][baseLevel]->Border == 0 && + t->Image[0][baseLevel]->TexFormat->MesaFormat == MESA_FORMAT_RGB) { + return &opt_sample_rgb_2d; + } + else if (t->WrapS == GL_REPEAT && + t->WrapT == GL_REPEAT && + t->_IsPowerOfTwo && + t->Image[0][baseLevel]->Border == 0 && + t->Image[0][baseLevel]->TexFormat->MesaFormat == MESA_FORMAT_RGBA) { + return &opt_sample_rgba_2d; + } + else { + return &sample_nearest_2d; + } + } + case GL_TEXTURE_3D: + if (needLambda) { + return &sample_lambda_3d; + } + else if (t->MinFilter == GL_LINEAR) { + return &sample_linear_3d; + } + else { + ASSERT(t->MinFilter == GL_NEAREST); + return &sample_nearest_3d; + } + case GL_TEXTURE_CUBE_MAP: + if (needLambda) { + return &sample_lambda_cube; + } + else if (t->MinFilter == GL_LINEAR) { + return &sample_linear_cube; + } + else { + ASSERT(t->MinFilter == GL_NEAREST); + return &sample_nearest_cube; + } + case GL_TEXTURE_RECTANGLE_NV: + if (needLambda) { + return &sample_lambda_rect; + } + else if (t->MinFilter == GL_LINEAR) { + return &sample_linear_rect; + } + else { + ASSERT(t->MinFilter == GL_NEAREST); + return &sample_nearest_rect; + } + default: + _mesa_problem(ctx, + "invalid target in _swrast_choose_texture_sample_func"); + return &null_sample_func; + } + } +} |