/**************************************************************************
*
* Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
* 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, sub license, 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 (including the
* next paragraph) 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 NON-INFRINGEMENT.
* IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS 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.
*
**************************************************************************/
/**
* Texture sampling
*
* Authors:
* Brian Paul
*/
#include "sp_context.h"
#include "sp_headers.h"
#include "sp_surface.h"
#include "sp_tex_sample.h"
#include "sp_tile_cache.h"
#include "pipe/p_context.h"
#include "pipe/p_defines.h"
#include "tgsi/tgsi_exec.h"
#include "util/u_math.h"
#include "util/u_memory.h"
/*
* 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) - util_ifloor(f))
/**
* Linear interpolation macro
*/
#define LERP(T, A, B) ( (A) + (T) * ((B) - (A)) )
/**
* 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 float
lerp_2d(float a, float b,
float v00, float v10, float v01, float v11)
{
const float temp0 = LERP(a, v00, v10);
const float temp1 = LERP(a, v01, v11);
return LERP(b, temp0, temp1);
}
/**
* 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.
*/
#define REMAINDER(A, B) ((unsigned) (A) % (unsigned) (B))
/**
* Apply texture coord wrapping mode and return integer texture index.
* \param wrapMode PIPE_TEX_WRAP_x
* \param s the texcoord
* \param size the texture image size
* \return integer texture index
*/
static INLINE int
nearest_texcoord(unsigned wrapMode, float s, unsigned size)
{
int i;
switch (wrapMode) {
case PIPE_TEX_WRAP_REPEAT:
/* s limited to [0,1) */
/* i limited to [0,size-1] */
i = util_ifloor(s * size);
i = REMAINDER(i, size);
return i;
case PIPE_TEX_WRAP_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 = util_ifloor(s * size);
return i;
case PIPE_TEX_WRAP_CLAMP_TO_EDGE:
{
/* s limited to [min,max] */
/* i limited to [0, size-1] */
const float min = 1.0F / (2.0F * size);
const float max = 1.0F - min;
if (s < min)
i = 0;
else if (s > max)
i = size - 1;
else
i = util_ifloor(s * size);
}
return i;
case PIPE_TEX_WRAP_CLAMP_TO_BORDER:
{
/* s limited to [min,max] */
/* i limited to [-1, size] */
const float min = -1.0F / (2.0F * size);
const float max = 1.0F - min;
if (s <= min)
i = -1;
else if (s >= max)
i = size;
else
i = util_ifloor(s * size);
}
return i;
case PIPE_TEX_WRAP_MIRROR_REPEAT:
{
const float min = 1.0F / (2.0F * size);
const float max = 1.0F - min;
const int flr = util_ifloor(s);
float u;
if (flr & 1)
u = 1.0F - (s - (float) flr);
else
u = s - (float) flr;
if (u < min)
i = 0;
else if (u > max)
i = size - 1;
else
i = util_ifloor(u * size);
}
return i;
case PIPE_TEX_WRAP_MIRROR_CLAMP:
{
/* s limited to [0,1] */
/* i limited to [0,size-1] */
const float u = fabsf(s);
if (u <= 0.0F)
i = 0;
else if (u >= 1.0F)
i = size - 1;
else
i = util_ifloor(u * size);
}
return i;
case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_EDGE:
{
/* s limited to [min,max] */
/* i limited to [0, size-1] */
const float min = 1.0F / (2.0F * size);
const float max = 1.0F - min;
const float u = fabsf(s);
if (u < min)
i = 0;
else if (u > max)
i = size - 1;
else
i = util_ifloor(u * size);
}
return i;
case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_BORDER:
{
/* s limited to [min,max] */
/* i limited to [0, size-1] */
const float min = -1.0F / (2.0F * size);
const float max = 1.0F - min;
const float u = fabsf(s);
if (u < min)
i = -1;
else if (u > max)
i = size;
else
i = util_ifloor(u * size);
}
return i;
default:
assert(0);
return 0;
}
}
/**
* Used to compute texel locations for linear sampling.
* \param wrapMode PIPE_TEX_WRAP_x
* \param s the texcoord
* \param size the texture image size
* \param i0 returns first texture index
* \param i1 returns second texture index (usually *i0 + 1)
* \param a returns blend factor/weight between texture indexes
*/
static INLINE void
linear_texcoord(unsigned wrapMode, float s, unsigned size,
int *i0, int *i1, float *a)
{
float u;
switch (wrapMode) {
case PIPE_TEX_WRAP_REPEAT:
u = s * size - 0.5F;
*i0 = REMAINDER(util_ifloor(u), size);
*i1 = REMAINDER(*i0 + 1, size);
break;
case PIPE_TEX_WRAP_CLAMP:
if (s <= 0.0F)
u = 0.0F;
else if (s >= 1.0F)
u = (float) size;
else
u = s * size;
u -= 0.5F;
*i0 = util_ifloor(u);
*i1 = *i0 + 1;
break;
case PIPE_TEX_WRAP_CLAMP_TO_EDGE:
if (s <= 0.0F)
u = 0.0F;
else if (s >= 1.0F)
u = (float) size;
else
u = s * size;
u -= 0.5F;
*i0 = util_ifloor(u);
*i1 = *i0 + 1;
if (*i0 < 0)
*i0 = 0;
if (*i1 >= (int) size)
*i1 = size - 1;
break;
case PIPE_TEX_WRAP_CLAMP_TO_BORDER:
{
const float min = -1.0F / (2.0F * size);
const float 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 = util_ifloor(u);
*i1 = *i0 + 1;
}
break;
case PIPE_TEX_WRAP_MIRROR_REPEAT:
{
const int flr = util_ifloor(s);
if (flr & 1)
u = 1.0F - (s - (float) flr);
else
u = s - (float) flr;
u = (u * size) - 0.5F;
*i0 = util_ifloor(u);
*i1 = *i0 + 1;
if (*i0 < 0)
*i0 = 0;
if (*i1 >= (int) size)
*i1 = size - 1;
}
break;
case PIPE_TEX_WRAP_MIRROR_CLAMP:
u = fabsf(s);
if (u >= 1.0F)
u = (float) size;
else
u *= size;
u -= 0.5F;
*i0 = util_ifloor(u);
*i1 = *i0 + 1;
break;
case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_EDGE:
u = fabsf(s);
if (u >= 1.0F)
u = (float) size;
else
u *= size;
u -= 0.5F;
*i0 = util_ifloor(u);
*i1 = *i0 + 1;
if (*i0 < 0)
*i0 = 0;
if (*i1 >= (int) size)
*i1 = size - 1;
break;
case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_BORDER:
{
const float min = -1.0F / (2.0F * size);
const float max = 1.0F - min;
u = fabsf(s);
if (u <= min)
u = min * size;
else if (u >= max)
u = max * size;
else
u *= size;
u -= 0.5F;
*i0 = util_ifloor(u);
*i1 = *i0 + 1;
}
break;
default:
assert(0);
}
*a = FRAC(u);
}
/**
* For RECT textures / unnormalized texcoords
* Only a subset of wrap modes supported.
*/
static INLINE int
nearest_texcoord_unnorm(unsigned wrapMode, float s, unsigned size)
{
int i;
switch (wrapMode) {
case PIPE_TEX_WRAP_CLAMP:
i = util_ifloor(s);
return CLAMP(i, 0, (int) size-1);
case PIPE_TEX_WRAP_CLAMP_TO_EDGE:
/* fall-through */
case PIPE_TEX_WRAP_CLAMP_TO_BORDER:
return util_ifloor( CLAMP(s, 0.5F, (float) size - 0.5F) );
default:
assert(0);
return 0;
}
}
/**
* For RECT textures / unnormalized texcoords.
* Only a subset of wrap modes supported.
*/
static INLINE void
linear_texcoord_unnorm(unsigned wrapMode, float s, unsigned size,
int *i0, int *i1, float *a)
{
switch (wrapMode) {
case PIPE_TEX_WRAP_CLAMP:
/* Not exactly what the spec says, but it matches NVIDIA output */
s = CLAMP(s - 0.5F, 0.0f, (float) size - 1.0f);
*i0 = util_ifloor(s);
*i1 = *i0 + 1;
break;
case PIPE_TEX_WRAP_CLAMP_TO_EDGE:
/* fall-through */
case PIPE_TEX_WRAP_CLAMP_TO_BORDER:
s = CLAMP(s, 0.5F, (float) size - 0.5F);
s -= 0.5F;
*i0 = util_ifloor(s);
*i1 = *i0 + 1;
if (*i1 > (int) size - 1)
*i1 = size - 1;
break;
default:
assert(0);
}
*a = FRAC(s);
}
static unsigned
choose_cube_face(float rx, float ry, float rz, float *newS, float *newT)
{
/*
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 float arx = fabsf(rx), ary = fabsf(ry), arz = fabsf(rz);
unsigned face;
float sc, tc, ma;
if (arx > ary && arx > arz) {
if (rx >= 0.0F) {
face = PIPE_TEX_FACE_POS_X;
sc = -rz;
tc = -ry;
ma = arx;
}
else {
face = PIPE_TEX_FACE_NEG_X;
sc = rz;
tc = -ry;
ma = arx;
}
}
else if (ary > arx && ary > arz) {
if (ry >= 0.0F) {
face = PIPE_TEX_FACE_POS_Y;
sc = rx;
tc = rz;
ma = ary;
}
else {
face = PIPE_TEX_FACE_NEG_Y;
sc = rx;
tc = -rz;
ma = ary;
}
}
else {
if (rz > 0.0F) {
face = PIPE_TEX_FACE_POS_Z;
sc = rx;
tc = -ry;
ma = arz;
}
else {
face = PIPE_TEX_FACE_NEG_Z;
sc = -rx;
tc = -ry;
ma = arz;
}
}
*newS = ( sc / ma + 1.0F ) * 0.5F;
*newT = ( tc / ma + 1.0F ) * 0.5F;
return face;
}
/**
* Examine the quad's texture coordinates to compute the partial
* derivatives w.r.t X and Y, then compute lambda (level of detail).
*
* This is only done for fragment shaders, not vertex shaders.
*/
static float
compute_lambda(struct tgsi_sampler *sampler,
const float s[QUAD_SIZE],
const float t[QUAD_SIZE],
const float p[QUAD_SIZE],
float lodbias)
{
float rho, lambda;
assert(sampler->state->normalized_coords);
assert(s);
{
float dsdx = s[QUAD_BOTTOM_RIGHT] - s[QUAD_BOTTOM_LEFT];
float dsdy = s[QUAD_TOP_LEFT] - s[QUAD_BOTTOM_LEFT];
dsdx = fabsf(dsdx);
dsdy = fabsf(dsdy);
rho = MAX2(dsdx, dsdy) * sampler->texture->width[0];
}
if (t) {
float dtdx = t[QUAD_BOTTOM_RIGHT] - t[QUAD_BOTTOM_LEFT];
float dtdy = t[QUAD_TOP_LEFT] - t[QUAD_BOTTOM_LEFT];
float max;
dtdx = fabsf(dtdx);
dtdy = fabsf(dtdy);
max = MAX2(dtdx, dtdy) * sampler->texture->height[0];
rho = MAX2(rho, max);
}
if (p) {
float dpdx = p[QUAD_BOTTOM_RIGHT] - p[QUAD_BOTTOM_LEFT];
float dpdy = p[QUAD_TOP_LEFT] - p[QUAD_BOTTOM_LEFT];
float max;
dpdx = fabsf(dpdx);
dpdy = fabsf(dpdy);
max = MAX2(dpdx, dpdy) * sampler->texture->depth[0];
rho = MAX2(rho, max);
}
lambda = util_fast_log2(rho);
lambda += lodbias + sampler->state->lod_bias;
lambda = CLAMP(lambda, sampler->state->min_lod, sampler->state->max_lod);
return lambda;
}
/**
* Do several things here:
* 1. Compute lambda from the texcoords, if needed
* 2. Determine if we're minifying or magnifying
* 3. If minifying, choose mipmap levels
* 4. Return image filter to use within mipmap images
*/
static void
choose_mipmap_levels(struct tgsi_sampler *sampler,
const float s[QUAD_SIZE],
const float t[QUAD_SIZE],
const float p[QUAD_SIZE],
float lodbias,
unsigned *level0, unsigned *level1, float *levelBlend,
unsigned *imgFilter)
{
if (sampler->state->min_mip_filter == PIPE_TEX_MIPFILTER_NONE) {
/* no mipmap selection needed */
*level0 = *level1 = CLAMP((int) sampler->state->min_lod,
0, (int) sampler->texture->last_level);
if (sampler->state->min_img_filter != sampler->state->mag_img_filter) {
/* non-mipmapped texture, but still need to determine if doing
* minification or magnification.
*/
float lambda = compute_lambda(sampler, s, t, p, lodbias);
if (lambda <= 0.0) {
*imgFilter = sampler->state->mag_img_filter;
}
else {
*imgFilter = sampler->state->min_img_filter;
}
}
else {
*imgFilter = sampler->state->mag_img_filter;
}
}
else {
float lambda;
if (1)
/* fragment shader */
lambda = compute_lambda(sampler, s, t, p, lodbias);
else
/* vertex shader */
lambda = lodbias; /* not really a bias, but absolute LOD */
if (lambda <= 0.0) { /* XXX threshold depends on the filter */
/* magnifying */
*imgFilter = sampler->state->mag_img_filter;
*level0 = *level1 = 0;
}
else {
/* minifying */
*imgFilter = sampler->state->min_img_filter;
/* choose mipmap level(s) and compute the blend factor between them */
if (sampler->state->min_mip_filter == PIPE_TEX_MIPFILTER_NEAREST) {
/* Nearest mipmap level */
const int lvl = (int) (lambda + 0.5);
*level0 =
*level1 = CLAMP(lvl, 0, (int) sampler->texture->last_level);
}
else {
/* Linear interpolation between mipmap levels */
const int lvl = (int) lambda;
*level0 = CLAMP(lvl, 0, (int) sampler->texture->last_level);
*level1 = CLAMP(lvl + 1, 0, (int) sampler->texture->last_level);
*levelBlend = FRAC(lambda); /* blending weight between levels */
}
}
}
}
/**
* Get a texel from a texture, using the texture tile cache.
*
* \param face the cube face in 0..5
* \param level the mipmap level
* \param x the x coord of texel within 2D image
* \param y the y coord of texel within 2D image
* \param z which slice of a 3D texture
* \param rgba the quad to put the texel/color into
* \param j which element of the rgba quad to write to
*
* XXX maybe move this into sp_tile_cache.c and merge with the
* sp_get_cached_tile_tex() function. Also, get 4 texels instead of 1...
*/
static void
get_texel(struct tgsi_sampler *sampler,
unsigned face, unsigned level, int x, int y, int z,
float rgba[NUM_CHANNELS][QUAD_SIZE], unsigned j)
{
if (x < 0 || x >= (int) sampler->texture->width[level] ||
y < 0 || y >= (int) sampler->texture->height[level] ||
z < 0 || z >= (int) sampler->texture->depth[level]) {
rgba[0][j] = sampler->state->border_color[0];
rgba[1][j] = sampler->state->border_color[1];
rgba[2][j] = sampler->state->border_color[2];
rgba[3][j] = sampler->state->border_color[3];
}
else {
const int tx = x % TILE_SIZE;
const int ty = y % TILE_SIZE;
const struct softpipe_cached_tile *tile
= sp_get_cached_tile_tex(sampler->pipe, sampler->cache,
x, y, z, face, level);
rgba[0][j] = tile->data.color[ty][tx][0];
rgba[1][j] = tile->data.color[ty][tx][1];
rgba[2][j] = tile->data.color[ty][tx][2];
rgba[3][j] = tile->data.color[ty][tx][3];
if (0)
{
debug_printf("Get texel %f %f %f %f from %s\n",
rgba[0][j], rgba[1][j], rgba[2][j], rgba[3][j],
pf_name(sampler->texture->format));
}
}
}
/**
* Compare texcoord 'p' (aka R) against texture value 'rgba[0]'
* When we sampled the depth texture, the depth value was put into all
* RGBA channels. We look at the red channel here.
*/
static INLINE void
shadow_compare(uint compare_func,
float rgba[NUM_CHANNELS][QUAD_SIZE],
const float p[QUAD_SIZE],
uint j)
{
int k;
switch (compare_func) {
case PIPE_FUNC_LESS:
k = p[j] < rgba[0][j];
break;
case PIPE_FUNC_LEQUAL:
k = p[j] <= rgba[0][j];
break;
case PIPE_FUNC_GREATER:
k = p[j] > rgba[0][j];
break;
case PIPE_FUNC_GEQUAL:
k = p[j] >= rgba[0][j];
break;
case PIPE_FUNC_EQUAL:
k = p[j] == rgba[0][j];
break;
case PIPE_FUNC_NOTEQUAL:
k = p[j] != rgba[0][j];
break;
case PIPE_FUNC_ALWAYS:
k = 1;
break;
case PIPE_FUNC_NEVER:
k = 0;
break;
default:
k = 0;
assert(0);
break;
}
rgba[0][j] = rgba[1][j] = rgba[2][j] = (float) k;
}
/**
* Common code for sampling 1D/2D/cube textures.
* Could probably extend for 3D...
*/
static void
sp_get_samples_2d_common(struct tgsi_sampler *sampler,
const float s[QUAD_SIZE],
const float t[QUAD_SIZE],
const float p[QUAD_SIZE],
float lodbias,
float rgba[NUM_CHANNELS][QUAD_SIZE],
const unsigned faces[4])
{
const uint compare_func = sampler->state->compare_func;
unsigned level0, level1, j, imgFilter;
int width, height;
float levelBlend;
choose_mipmap_levels(sampler, s, t, p, lodbias,
&level0, &level1, &levelBlend, &imgFilter);
assert(sampler->state->normalized_coords);
width = sampler->texture->width[level0];
height = sampler->texture->height[level0];
assert(width > 0);
switch (imgFilter) {
case PIPE_TEX_FILTER_NEAREST:
for (j = 0; j < QUAD_SIZE; j++) {
int x = nearest_texcoord(sampler->state->wrap_s, s[j], width);
int y = nearest_texcoord(sampler->state->wrap_t, t[j], height);
get_texel(sampler, faces[j], level0, x, y, 0, rgba, j);
if (sampler->state->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE) {
shadow_compare(compare_func, rgba, p, j);
}
if (level0 != level1) {
/* get texels from second mipmap level and blend */
float rgba2[4][4];
unsigned c;
x = x / 2;
y = y / 2;
get_texel(sampler, faces[j], level1, x, y, 0, rgba2, j);
if (sampler->state->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE){
shadow_compare(compare_func, rgba2, p, j);
}
for (c = 0; c < NUM_CHANNELS; c++) {
rgba[c][j] = LERP(levelBlend, rgba[c][j], rgba2[c][j]);
}
}
}
break;
case PIPE_TEX_FILTER_LINEAR:
case PIPE_TEX_FILTER_ANISO:
for (j = 0; j < QUAD_SIZE; j++) {
float tx[4][4], a, b;
int x0, y0, x1, y1, c;
linear_texcoord(sampler->state->wrap_s, s[j], width, &x0, &x1, &a);
linear_texcoord(sampler->state->wrap_t, t[j], height, &y0, &y1, &b);
get_texel(sampler, faces[j], level0, x0, y0, 0, tx, 0);
get_texel(sampler, faces[j], level0, x1, y0, 0, tx, 1);
get_texel(sampler, faces[j], level0, x0, y1, 0, tx, 2);
get_texel(sampler, faces[j], level0, x1, y1, 0, tx, 3);
if (sampler->state->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE) {
shadow_compare(compare_func, tx, p, 0);
shadow_compare(compare_func, tx, p, 1);
shadow_compare(compare_func, tx, p, 2);
shadow_compare(compare_func, tx, p, 3);
}
for (c = 0; c < 4; c++) {
rgba[c][j] = lerp_2d(a, b, tx[c][0], tx[c][1], tx[c][2], tx[c][3]);
}
if (level0 != level1) {
/* get texels from second mipmap level and blend */
float rgba2[4][4];
x0 = x0 / 2;
y0 = y0 / 2;
x1 = x1 / 2;
y1 = y1 / 2;
get_texel(sampler, faces[j], level1, x0, y0, 0, tx, 0);
get_texel(sampler, faces[j], level1, x1, y0, 0, tx, 1);
get_texel(sampler, faces[j], level1, x0, y1, 0, tx, 2);
get_texel(sampler, faces[j], level1, x1, y1, 0, tx, 3);
if (sampler->state->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE){
shadow_compare(compare_func, tx, p, 0);
shadow_compare(compare_func, tx, p, 1);
shadow_compare(compare_func, tx, p, 2);
shadow_compare(compare_func, tx, p, 3);
}
for (c = 0; c < 4; c++) {
rgba2[c][j] = lerp_2d(a, b,
tx[c][0], tx[c][1], tx[c][2], tx[c][3]);
}
for (c = 0; c < NUM_CHANNELS; c++) {
rgba[c][j] = LERP(levelBlend, rgba[c][j], rgba2[c][j]);
}
}
}
break;
default:
assert(0);
}
}
static void
sp_get_samples_1d(struct tgsi_sampler *sampler,
const float s[QUAD_SIZE],
const float t[QUAD_SIZE],
const float p[QUAD_SIZE],
float lodbias,
float rgba[NUM_CHANNELS][QUAD_SIZE])
{
static const unsigned faces[4] = {0, 0, 0, 0};
static const float tzero[4] = {0, 0, 0, 0};
sp_get_samples_2d_common(sampler, s, tzero, NULL, lodbias, rgba, faces);
}
static void
sp_get_samples_2d(struct tgsi_sampler *sampler,
const float s[QUAD_SIZE],
const float t[QUAD_SIZE],
const float p[QUAD_SIZE],
float lodbias,
float rgba[NUM_CHANNELS][QUAD_SIZE])
{
static const unsigned faces[4] = {0, 0, 0, 0};
sp_get_samples_2d_common(sampler, s, t, p, lodbias, rgba, faces);
}
static void
sp_get_samples_3d(struct tgsi_sampler *sampler,
const float s[QUAD_SIZE],
const float t[QUAD_SIZE],
const float p[QUAD_SIZE],
float lodbias,
float rgba[NUM_CHANNELS][QUAD_SIZE])
{
/* get/map pipe_surfaces corresponding to 3D tex slices */
unsigned level0, level1, j, imgFilter;
int width, height, depth;
float levelBlend;
const uint face = 0;
choose_mipmap_levels(sampler, s, t, p, lodbias,
&level0, &level1, &levelBlend, &imgFilter);
assert(sampler->state->normalized_coords);
width = sampler->texture->width[level0];
height = sampler->texture->height[level0];
depth = sampler->texture->depth[level0];
assert(width > 0);
assert(height > 0);
assert(depth > 0);
switch (imgFilter) {
case PIPE_TEX_FILTER_NEAREST:
for (j = 0; j < QUAD_SIZE; j++) {
int x = nearest_texcoord(sampler->state->wrap_s, s[j], width);
int y = nearest_texcoord(sampler->state->wrap_t, t[j], height);
int z = nearest_texcoord(sampler->state->wrap_r, p[j], depth);
get_texel(sampler, face, level0, x, y, z, rgba, j);
if (level0 != level1) {
/* get texels from second mipmap level and blend */
float rgba2[4][4];
unsigned c;
x /= 2;
y /= 2;
z /= 2;
get_texel(sampler, face, level1, x, y, z, rgba2, j);
for (c = 0; c < NUM_CHANNELS; c++) {
rgba[c][j] = LERP(levelBlend, rgba2[c][j], rgba[c][j]);
}
}
}
break;
case PIPE_TEX_FILTER_LINEAR:
case PIPE_TEX_FILTER_ANISO:
for (j = 0; j < QUAD_SIZE; j++) {
float texel0[4][4], texel1[4][4];
float xw, yw, zw; /* interpolation weights */
int x0, x1, y0, y1, z0, z1, c;
linear_texcoord(sampler->state->wrap_s, s[j], width, &x0, &x1, &xw);
linear_texcoord(sampler->state->wrap_t, t[j], height, &y0, &y1, &yw);
linear_texcoord(sampler->state->wrap_r, p[j], depth, &z0, &z1, &zw);
get_texel(sampler, face, level0, x0, y0, z0, texel0, 0);
get_texel(sampler, face, level0, x1, y0, z0, texel0, 1);
get_texel(sampler, face, level0, x0, y1, z0, texel0, 2);
get_texel(sampler, face, level0, x1, y1, z0, texel0, 3);
get_texel(sampler, face, level0, x0, y0, z1, texel1, 0);
get_texel(sampler, face, level0, x1, y0, z1, texel1, 1);
get_texel(sampler, face, level0, x0, y1, z1, texel1, 2);
get_texel(sampler, face, level0, x1, y1, z1, texel1, 3);
/* 3D lerp */
for (c = 0; c < 4; c++) {
float ctemp0[4][4], ctemp1[4][4];
ctemp0[c][j] = lerp_2d(xw, yw,
texel0[c][0], texel0[c][1],
texel0[c][2], texel0[c][3]);
ctemp1[c][j] = lerp_2d(xw, yw,
texel1[c][0], texel1[c][1],
texel1[c][2], texel1[c][3]);
rgba[c][j] = LERP(zw, ctemp0[c][j], ctemp1[c][j]);
}
if (level0 != level1) {
/* get texels from second mipmap level and blend */
float rgba2[4][4];
x0 /= 2;
y0 /= 2;
z0 /= 2;
x1 /= 2;
y1 /= 2;
z1 /= 2;
get_texel(sampler, face, level1, x0, y0, z0, texel0, 0);
get_texel(sampler, face, level1, x1, y0, z0, texel0, 1);
get_texel(sampler, face, level1, x0, y1, z0, texel0, 2);
get_texel(sampler, face, level1, x1, y1, z0, texel0, 3);
get_texel(sampler, face, level1, x0, y0, z1, texel1, 0);
get_texel(sampler, face, level1, x1, y0, z1, texel1, 1);
get_texel(sampler, face, level1, x0, y1, z1, texel1, 2);
get_texel(sampler, face, level1, x1, y1, z1, texel1, 3);
/* 3D lerp */
for (c = 0; c < 4; c++) {
float ctemp0[4][4], ctemp1[4][4];
ctemp0[c][j] = lerp_2d(xw, yw,
texel0[c][0], texel0[c][1],
texel0[c][2], texel0[c][3]);
ctemp1[c][j] = lerp_2d(xw, yw,
texel1[c][0], texel1[c][1],
texel1[c][2], texel1[c][3]);
rgba2[c][j] = LERP(zw, ctemp0[c][j], ctemp1[c][j]);
}
/* blend mipmap levels */
for (c = 0; c < NUM_CHANNELS; c++) {
rgba[c][j] = LERP(levelBlend, rgba[c][j], rgba2[c][j]);
}
}
}
break;
default:
assert(0);
}
}
static void
sp_get_samples_cube(struct tgsi_sampler *sampler,
const float s[QUAD_SIZE],
const float t[QUAD_SIZE],
const float p[QUAD_SIZE],
float lodbias,
float rgba[NUM_CHANNELS][QUAD_SIZE])
{
unsigned faces[QUAD_SIZE], j;
float ssss[4], tttt[4];
for (j = 0; j < QUAD_SIZE; j++) {
faces[j] = choose_cube_face(s[j], t[j], p[j], ssss + j, tttt + j);
}
sp_get_samples_2d_common(sampler, ssss, tttt, NULL, lodbias, rgba, faces);
}
static void
sp_get_samples_rect(struct tgsi_sampler *sampler,
const float s[QUAD_SIZE],
const float t[QUAD_SIZE],
const float p[QUAD_SIZE],
float lodbias,
float rgba[NUM_CHANNELS][QUAD_SIZE])
{
//sp_get_samples_2d_common(sampler, s, t, p, lodbias, rgba, faces);
static const uint face = 0;
const uint compare_func = sampler->state->compare_func;
unsigned level0, level1, j, imgFilter;
int width, height;
float levelBlend;
choose_mipmap_levels(sampler, s, t, p, lodbias,
&level0, &level1, &levelBlend, &imgFilter);
/* texture RECTS cannot be mipmapped */
assert(level0 == level1);
width = sampler->texture->width[level0];
height = sampler->texture->height[level0];
assert(width > 0);
switch (imgFilter) {
case PIPE_TEX_FILTER_NEAREST:
for (j = 0; j < QUAD_SIZE; j++) {
int x = nearest_texcoord_unnorm(sampler->state->wrap_s, s[j], width);
int y = nearest_texcoord_unnorm(sampler->state->wrap_t, t[j], height);
get_texel(sampler, face, level0, x, y, 0, rgba, j);
if (sampler->state->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE) {
shadow_compare(compare_func, rgba, p, j);
}
}
break;
case PIPE_TEX_FILTER_LINEAR:
case PIPE_TEX_FILTER_ANISO:
for (j = 0; j < QUAD_SIZE; j++) {
float tx[4][4], a, b;
int x0, y0, x1, y1, c;
linear_texcoord_unnorm(sampler->state->wrap_s, s[j], width, &x0, &x1, &a);
linear_texcoord_unnorm(sampler->state->wrap_t, t[j], height, &y0, &y1, &b);
get_texel(sampler, face, level0, x0, y0, 0, tx, 0);
get_texel(sampler, face, level0, x1, y0, 0, tx, 1);
get_texel(sampler, face, level0, x0, y1, 0, tx, 2);
get_texel(sampler, face, level0, x1, y1, 0, tx, 3);
if (sampler->state->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE) {
shadow_compare(compare_func, tx, p, 0);
shadow_compare(compare_func, tx, p, 1);
shadow_compare(compare_func, tx, p, 2);
shadow_compare(compare_func, tx, p, 3);
}
for (c = 0; c < 4; c++) {
rgba[c][j] = lerp_2d(a, b, tx[c][0], tx[c][1], tx[c][2], tx[c][3]);
}
}
break;
default:
assert(0);
}
}
/**
* Called via tgsi_sampler::get_samples()
* Use the sampler's state setting to get a filtered RGBA value
* from the sampler's texture.
*
* XXX we can implement many versions of this function, each
* tightly coded for a specific combination of sampler state
* (nearest + repeat), (bilinear mipmap + clamp), etc.
*
* The update_samplers() function in st_atom_sampler.c could create
* a new tgsi_sampler object for each state combo it finds....
*/
void
sp_get_samples(struct tgsi_sampler *sampler,
const float s[QUAD_SIZE],
const float t[QUAD_SIZE],
const float p[QUAD_SIZE],
float lodbias,
float rgba[NUM_CHANNELS][QUAD_SIZE])
{
if (!sampler->texture)
return;
switch (sampler->texture->target) {
case PIPE_TEXTURE_1D:
assert(sampler->state->normalized_coords);
sp_get_samples_1d(sampler, s, t, p, lodbias, rgba);
break;
case PIPE_TEXTURE_2D:
if (sampler->state->normalized_coords)
sp_get_samples_2d(sampler, s, t, p, lodbias, rgba);
else
sp_get_samples_rect(sampler, s, t, p, lodbias, rgba);
break;
case PIPE_TEXTURE_3D:
assert(sampler->state->normalized_coords);
sp_get_samples_3d(sampler, s, t, p, lodbias, rgba);
break;
case PIPE_TEXTURE_CUBE:
assert(sampler->state->normalized_coords);
sp_get_samples_cube(sampler, s, t, p, lodbias, rgba);
break;
default:
assert(0);
}
#if 0 /* DEBUG */
{
int i;
printf("Sampled at %f, %f, %f:\n", s[0], t[0], p[0]);
for (i = 0; i < 4; i++) {
printf("Frag %d: %f %f %f %f\n", i,
rgba[0][i],
rgba[1][i],
rgba[2][i],
rgba[3][i]);
}
}
#endif
}