reactos/dll/3rdparty/dxtn/fxt1.c
Cameron Gutman c2d0d784c7 [USB-BRINGUP-TRUNK]
- Create a branch to do a proper merge of USB work from a trunk base instead of from cmake-bringup
- In the future, DO NOT under any circumstances branch another branch. This leads to merge problems!

svn path=/branches/usb-bringup-trunk/; revision=55018
2012-01-20 20:58:46 +00:00

1369 lines
33 KiB
C

/*
* FXT1 codec
* Version: 1.1
*
* Copyright (C) 2004 Daniel Borca 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
* DANIEL BORCA 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 <stdlib.h>
#include <string.h>
#include "types.h"
#include "internal.h"
#include "fxt1.h"
/***************************************************************************\
* FXT1 encoder
*
* The encoder was built by reversing the decoder,
* and is vaguely based on Texus2 by 3dfx. Note that this code
* is merely a proof of concept, since it is highly UNoptimized;
* moreover, it is sub-optimal due to initial conditions passed
* to Lloyd's algorithm (the interpolation modes are even worse).
\***************************************************************************/
#define MAX_COMP 4 /* ever needed maximum number of components in texel */
#define MAX_VECT 4 /* ever needed maximum number of base vectors to find */
#define N_TEXELS 32 /* number of texels in a block (always 32) */
#define LL_N_REP 50 /* number of iterations in lloyd's vq */
#define LL_RMS_D 10 /* fault tolerance (maximum delta) */
#define LL_RMS_E 255 /* fault tolerance (maximum error) */
#define ALPHA_TS 2 /* alpha threshold: (255 - ALPHA_TS) deemed opaque */
#define ISTBLACK(v) (*((dword *)(v)) == 0)
#define COPY_4UBV(DST, SRC) *((dword *)(DST)) = *((dword *)(SRC))
static int
fxt1_bestcol (float vec[][MAX_COMP], int nv,
byte input[MAX_COMP], int nc)
{
int i, j, best = -1;
float err = 1e9; /* big enough */
for (j = 0; j < nv; j++) {
float e = 0.0F;
for (i = 0; i < nc; i++) {
e += (vec[j][i] - input[i]) * (vec[j][i] - input[i]);
}
if (e < err) {
err = e;
best = j;
}
}
return best;
}
static int
fxt1_worst (float vec[MAX_COMP],
byte input[N_TEXELS][MAX_COMP], int nc, int n)
{
int i, k, worst = -1;
float err = -1.0F; /* small enough */
for (k = 0; k < n; k++) {
float e = 0.0F;
for (i = 0; i < nc; i++) {
e += (vec[i] - input[k][i]) * (vec[i] - input[k][i]);
}
if (e > err) {
err = e;
worst = k;
}
}
return worst;
}
static int
fxt1_variance (double variance[MAX_COMP],
byte input[N_TEXELS][MAX_COMP], int nc, int n)
{
int i, k, best = 0;
dword sx, sx2;
double var, maxvar = -1; /* small enough */
double teenth = 1.0 / n;
for (i = 0; i < nc; i++) {
sx = sx2 = 0;
for (k = 0; k < n; k++) {
int t = input[k][i];
sx += t;
sx2 += t * t;
}
var = sx2 * teenth - sx * sx * teenth * teenth;
if (maxvar < var) {
maxvar = var;
best = i;
}
if (variance) {
variance[i] = var;
}
}
return best;
}
static int
fxt1_choose (float vec[][MAX_COMP], int nv,
byte input[N_TEXELS][MAX_COMP], int nc, int n)
{
#if 0
/* Choose colors from a grid.
*/
int i, j;
for (j = 0; j < nv; j++) {
int m = j * (n - 1) / (nv - 1);
for (i = 0; i < nc; i++) {
vec[j][i] = input[m][i];
}
}
#else
/* Our solution here is to find the darkest and brightest colors in
* the 8x4 tile and use those as the two representative colors.
* There are probably better algorithms to use (histogram-based).
*/
int i, j, k;
int minSum = 2000; /* big enough */
int maxSum = -1; /* small enough */
int minCol = 0; /* phoudoin: silent compiler! */
int maxCol = 0; /* phoudoin: silent compiler! */
struct {
int flag;
dword key;
int freq;
int idx;
} hist[N_TEXELS];
int lenh = 0;
memset(hist, 0, sizeof(hist));
for (k = 0; k < n; k++) {
int l;
dword key = 0;
int sum = 0;
for (i = 0; i < nc; i++) {
key <<= 8;
key |= input[k][i];
sum += input[k][i];
}
for (l = 0; l < n; l++) {
if (!hist[l].flag) {
/* alloc new slot */
hist[l].flag = !0;
hist[l].key = key;
hist[l].freq = 1;
hist[l].idx = k;
lenh = l + 1;
break;
} else if (hist[l].key == key) {
hist[l].freq++;
break;
}
}
if (minSum > sum) {
minSum = sum;
minCol = k;
}
if (maxSum < sum) {
maxSum = sum;
maxCol = k;
}
}
if (lenh <= nv) {
for (j = 0; j < lenh; j++) {
for (i = 0; i < nc; i++) {
vec[j][i] = (float)input[hist[j].idx][i];
}
}
for (; j < nv; j++) {
for (i = 0; i < nc; i++) {
vec[j][i] = vec[0][i];
}
}
return 0;
}
for (j = 0; j < nv; j++) {
for (i = 0; i < nc; i++) {
vec[j][i] = ((nv - 1 - j) * input[minCol][i] + j * input[maxCol][i] + (nv - 1) / 2) / (float)(nv - 1);
}
}
#endif
return !0;
}
static int
fxt1_lloyd (float vec[][MAX_COMP], int nv,
byte input[N_TEXELS][MAX_COMP], int nc, int n)
{
/* Use the generalized lloyd's algorithm for VQ:
* find 4 color vectors.
*
* for each sample color
* sort to nearest vector.
*
* replace each vector with the centroid of it's matching colors.
*
* repeat until RMS doesn't improve.
*
* if a color vector has no samples, or becomes the same as another
* vector, replace it with the color which is farthest from a sample.
*
* vec[][MAX_COMP] initial vectors and resulting colors
* nv number of resulting colors required
* input[N_TEXELS][MAX_COMP] input texels
* nc number of components in input / vec
* n number of input samples
*/
int sum[MAX_VECT][MAX_COMP]; /* used to accumulate closest texels */
int cnt[MAX_VECT]; /* how many times a certain vector was chosen */
float error, lasterror = 1e9;
int i, j, k, rep;
/* the quantizer */
for (rep = 0; rep < LL_N_REP; rep++) {
/* reset sums & counters */
for (j = 0; j < nv; j++) {
for (i = 0; i < nc; i++) {
sum[j][i] = 0;
}
cnt[j] = 0;
}
error = 0;
/* scan whole block */
for (k = 0; k < n; k++) {
#if 1
int best = -1;
float err = 1e9; /* big enough */
/* determine best vector */
for (j = 0; j < nv; j++) {
float e = (vec[j][0] - input[k][0]) * (vec[j][0] - input[k][0]) +
(vec[j][1] - input[k][1]) * (vec[j][1] - input[k][1]) +
(vec[j][2] - input[k][2]) * (vec[j][2] - input[k][2]);
if (nc == 4) {
e += (vec[j][3] - input[k][3]) * (vec[j][3] - input[k][3]);
}
if (e < err) {
err = e;
best = j;
}
}
#else
int best = fxt1_bestcol(vec, nv, input[k], nc, &err);
#endif
/* add in closest color */
for (i = 0; i < nc; i++) {
sum[best][i] += input[k][i];
}
/* mark this vector as used */
cnt[best]++;
/* accumulate error */
error += err;
}
/* check RMS */
if ((error < LL_RMS_E) ||
((error < lasterror) && ((lasterror - error) < LL_RMS_D))) {
return !0; /* good match */
}
lasterror = error;
/* move each vector to the barycenter of its closest colors */
for (j = 0; j < nv; j++) {
if (cnt[j]) {
float div = 1.0F / cnt[j];
for (i = 0; i < nc; i++) {
vec[j][i] = div * sum[j][i];
}
} else {
/* this vec has no samples or is identical with a previous vec */
int worst = fxt1_worst(vec[j], input, nc, n);
for (i = 0; i < nc; i++) {
vec[j][i] = input[worst][i];
}
}
}
}
return 0; /* could not converge fast enough */
}
static void
fxt1_quantize_CHROMA (dword *cc,
byte input[N_TEXELS][MAX_COMP])
{
const int n_vect = 4; /* 4 base vectors to find */
const int n_comp = 3; /* 3 components: R, G, B */
float vec[MAX_VECT][MAX_COMP];
int i, j, k;
qword hi; /* high quadword */
dword lohi, lolo; /* low quadword: hi dword, lo dword */
if (fxt1_choose(vec, n_vect, input, n_comp, N_TEXELS) != 0) {
fxt1_lloyd(vec, n_vect, input, n_comp, N_TEXELS);
}
Q_MOV32(hi, 4); /* cc-chroma = "010" + unused bit */
for (j = n_vect - 1; j >= 0; j--) {
for (i = 0; i < n_comp; i++) {
/* add in colors */
Q_SHL(hi, 5);
Q_OR32(hi, (dword)(vec[j][i] / 8.0F));
}
}
((qword *)cc)[1] = hi;
lohi = lolo = 0;
/* right microtile */
for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) {
lohi <<= 2;
lohi |= fxt1_bestcol(vec, n_vect, input[k], n_comp);
}
/* left microtile */
for (; k >= 0; k--) {
lolo <<= 2;
lolo |= fxt1_bestcol(vec, n_vect, input[k], n_comp);
}
cc[1] = lohi;
cc[0] = lolo;
}
static void
fxt1_quantize_ALPHA0 (dword *cc,
byte input[N_TEXELS][MAX_COMP],
byte reord[N_TEXELS][MAX_COMP], int n)
{
const int n_vect = 3; /* 3 base vectors to find */
const int n_comp = 4; /* 4 components: R, G, B, A */
float vec[MAX_VECT][MAX_COMP];
int i, j, k;
qword hi; /* high quadword */
dword lohi, lolo; /* low quadword: hi dword, lo dword */
/* the last vector indicates zero */
for (i = 0; i < n_comp; i++) {
vec[n_vect][i] = 0;
}
/* the first n texels in reord are guaranteed to be non-zero */
if (fxt1_choose(vec, n_vect, reord, n_comp, n) != 0) {
fxt1_lloyd(vec, n_vect, reord, n_comp, n);
}
Q_MOV32(hi, 6); /* alpha = "011" + lerp = 0 */
for (j = n_vect - 1; j >= 0; j--) {
/* add in alphas */
Q_SHL(hi, 5);
Q_OR32(hi, (dword)(vec[j][ACOMP] / 8.0F));
}
for (j = n_vect - 1; j >= 0; j--) {
for (i = 0; i < n_comp - 1; i++) {
/* add in colors */
Q_SHL(hi, 5);
Q_OR32(hi, (dword)(vec[j][i] / 8.0F));
}
}
((qword *)cc)[1] = hi;
lohi = lolo = 0;
/* right microtile */
for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) {
lohi <<= 2;
lohi |= fxt1_bestcol(vec, n_vect + 1, input[k], n_comp);
}
/* left microtile */
for (; k >= 0; k--) {
lolo <<= 2;
lolo |= fxt1_bestcol(vec, n_vect + 1, input[k], n_comp);
}
cc[1] = lohi;
cc[0] = lolo;
}
static void
fxt1_quantize_ALPHA1 (dword *cc,
byte input[N_TEXELS][MAX_COMP])
{
const int n_vect = 3; /* highest vector number in each microtile */
const int n_comp = 4; /* 4 components: R, G, B, A */
float vec[1 + 1 + 1][MAX_COMP]; /* 1.5 extrema for each sub-block */
float b, iv[MAX_COMP]; /* interpolation vector */
int i, j, k;
qword hi; /* high quadword */
dword lohi, lolo; /* low quadword: hi dword, lo dword */
int minSum;
int maxSum;
int minColL = 0, maxColL = 0;
int minColR = 0, maxColR = 0;
int sumL = 0, sumR = 0;
/* Our solution here is to find the darkest and brightest colors in
* the 4x4 tile and use those as the two representative colors.
* There are probably better algorithms to use (histogram-based).
*/
minSum = 2000; /* big enough */
maxSum = -1; /* small enough */
for (k = 0; k < N_TEXELS / 2; k++) {
int sum = 0;
for (i = 0; i < n_comp; i++) {
sum += input[k][i];
}
if (minSum > sum) {
minSum = sum;
minColL = k;
}
if (maxSum < sum) {
maxSum = sum;
maxColL = k;
}
sumL += sum;
}
minSum = 2000; /* big enough */
maxSum = -1; /* small enough */
for (; k < N_TEXELS; k++) {
int sum = 0;
for (i = 0; i < n_comp; i++) {
sum += input[k][i];
}
if (minSum > sum) {
minSum = sum;
minColR = k;
}
if (maxSum < sum) {
maxSum = sum;
maxColR = k;
}
sumR += sum;
}
/* choose the common vector (yuck!) */
{
int j1, j2;
int v1 = 0, v2 = 0;
float err = 1e9; /* big enough */
float tv[2 * 2][MAX_COMP]; /* 2 extrema for each sub-block */
for (i = 0; i < n_comp; i++) {
tv[0][i] = input[minColL][i];
tv[1][i] = input[maxColL][i];
tv[2][i] = input[minColR][i];
tv[3][i] = input[maxColR][i];
}
for (j1 = 0; j1 < 2; j1++) {
for (j2 = 2; j2 < 4; j2++) {
float e = 0.0F;
for (i = 0; i < n_comp; i++) {
e += (tv[j1][i] - tv[j2][i]) * (tv[j1][i] - tv[j2][i]);
}
if (e < err) {
err = e;
v1 = j1;
v2 = j2;
}
}
}
for (i = 0; i < n_comp; i++) {
vec[0][i] = tv[1 - v1][i];
vec[1][i] = (tv[v1][i] * sumL + tv[v2][i] * sumR) / (sumL + sumR);
vec[2][i] = tv[5 - v2][i];
}
}
/* left microtile */
cc[0] = 0;
if (minColL != maxColL) {
/* compute interpolation vector */
MAKEIVEC(n_vect, n_comp, iv, b, vec[0], vec[1]);
/* add in texels */
lolo = 0;
for (k = N_TEXELS / 2 - 1; k >= 0; k--) {
int texel;
/* interpolate color */
CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
/* add in texel */
lolo <<= 2;
lolo |= texel;
}
cc[0] = lolo;
}
/* right microtile */
cc[1] = 0;
if (minColR != maxColR) {
/* compute interpolation vector */
MAKEIVEC(n_vect, n_comp, iv, b, vec[2], vec[1]);
/* add in texels */
lohi = 0;
for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) {
int texel;
/* interpolate color */
CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
/* add in texel */
lohi <<= 2;
lohi |= texel;
}
cc[1] = lohi;
}
Q_MOV32(hi, 7); /* alpha = "011" + lerp = 1 */
for (j = n_vect - 1; j >= 0; j--) {
/* add in alphas */
Q_SHL(hi, 5);
Q_OR32(hi, (dword)(vec[j][ACOMP] / 8.0F));
}
for (j = n_vect - 1; j >= 0; j--) {
for (i = 0; i < n_comp - 1; i++) {
/* add in colors */
Q_SHL(hi, 5);
Q_OR32(hi, (dword)(vec[j][i] / 8.0F));
}
}
((qword *)cc)[1] = hi;
}
static void
fxt1_quantize_HI (dword *cc,
byte input[N_TEXELS][MAX_COMP],
byte reord[N_TEXELS][MAX_COMP], int n)
{
const int n_vect = 6; /* highest vector number */
const int n_comp = 3; /* 3 components: R, G, B */
float b = 0.0F; /* phoudoin: silent compiler! */
float iv[MAX_COMP]; /* interpolation vector */
int i, k;
dword hihi; /* high quadword: hi dword */
int minSum = 2000; /* big enough */
int maxSum = -1; /* small enough */
int minCol = 0; /* phoudoin: silent compiler! */
int maxCol = 0; /* phoudoin: silent compiler! */
/* Our solution here is to find the darkest and brightest colors in
* the 8x4 tile and use those as the two representative colors.
* There are probably better algorithms to use (histogram-based).
*/
for (k = 0; k < n; k++) {
int sum = 0;
for (i = 0; i < n_comp; i++) {
sum += reord[k][i];
}
if (minSum > sum) {
minSum = sum;
minCol = k;
}
if (maxSum < sum) {
maxSum = sum;
maxCol = k;
}
}
hihi = 0; /* cc-hi = "00" */
for (i = 0; i < n_comp; i++) {
/* add in colors */
hihi <<= 5;
hihi |= reord[maxCol][i] >> 3;
}
for (i = 0; i < n_comp; i++) {
/* add in colors */
hihi <<= 5;
hihi |= reord[minCol][i] >> 3;
}
cc[3] = hihi;
cc[0] = cc[1] = cc[2] = 0;
/* compute interpolation vector */
if (minCol != maxCol) {
MAKEIVEC(n_vect, n_comp, iv, b, reord[minCol], reord[maxCol]);
}
/* add in texels */
for (k = N_TEXELS - 1; k >= 0; k--) {
int t = k * 3;
dword *kk = (dword *)((byte *)cc + t / 8);
int texel = n_vect + 1; /* transparent black */
if (!ISTBLACK(input[k])) {
if (minCol != maxCol) {
/* interpolate color */
CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
/* add in texel */
kk[0] |= texel << (t & 7);
}
} else {
/* add in texel */
kk[0] |= texel << (t & 7);
}
}
}
static void
fxt1_quantize_MIXED1 (dword *cc,
byte input[N_TEXELS][MAX_COMP])
{
const int n_vect = 2; /* highest vector number in each microtile */
const int n_comp = 3; /* 3 components: R, G, B */
byte vec[2 * 2][MAX_COMP]; /* 2 extrema for each sub-block */
float b, iv[MAX_COMP]; /* interpolation vector */
int i, j, k;
qword hi; /* high quadword */
dword lohi, lolo; /* low quadword: hi dword, lo dword */
int minSum;
int maxSum;
int minColL = 0, maxColL = -1;
int minColR = 0, maxColR = -1;
/* Our solution here is to find the darkest and brightest colors in
* the 4x4 tile and use those as the two representative colors.
* There are probably better algorithms to use (histogram-based).
*/
minSum = 2000; /* big enough */
maxSum = -1; /* small enough */
for (k = 0; k < N_TEXELS / 2; k++) {
if (!ISTBLACK(input[k])) {
int sum = 0;
for (i = 0; i < n_comp; i++) {
sum += input[k][i];
}
if (minSum > sum) {
minSum = sum;
minColL = k;
}
if (maxSum < sum) {
maxSum = sum;
maxColL = k;
}
}
}
minSum = 2000; /* big enough */
maxSum = -1; /* small enough */
for (; k < N_TEXELS; k++) {
if (!ISTBLACK(input[k])) {
int sum = 0;
for (i = 0; i < n_comp; i++) {
sum += input[k][i];
}
if (minSum > sum) {
minSum = sum;
minColR = k;
}
if (maxSum < sum) {
maxSum = sum;
maxColR = k;
}
}
}
/* left microtile */
if (maxColL == -1) {
/* all transparent black */
cc[0] = ~0UL;
for (i = 0; i < n_comp; i++) {
vec[0][i] = 0;
vec[1][i] = 0;
}
} else {
cc[0] = 0;
for (i = 0; i < n_comp; i++) {
vec[0][i] = input[minColL][i];
vec[1][i] = input[maxColL][i];
}
if (minColL != maxColL) {
/* compute interpolation vector */
MAKEIVEC(n_vect, n_comp, iv, b, vec[0], vec[1]);
/* add in texels */
lolo = 0;
for (k = N_TEXELS / 2 - 1; k >= 0; k--) {
int texel = n_vect + 1; /* transparent black */
if (!ISTBLACK(input[k])) {
/* interpolate color */
CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
}
/* add in texel */
lolo <<= 2;
lolo |= texel;
}
cc[0] = lolo;
}
}
/* right microtile */
if (maxColR == -1) {
/* all transparent black */
cc[1] = ~0UL;
for (i = 0; i < n_comp; i++) {
vec[2][i] = 0;
vec[3][i] = 0;
}
} else {
cc[1] = 0;
for (i = 0; i < n_comp; i++) {
vec[2][i] = input[minColR][i];
vec[3][i] = input[maxColR][i];
}
if (minColR != maxColR) {
/* compute interpolation vector */
MAKEIVEC(n_vect, n_comp, iv, b, vec[2], vec[3]);
/* add in texels */
lohi = 0;
for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) {
int texel = n_vect + 1; /* transparent black */
if (!ISTBLACK(input[k])) {
/* interpolate color */
CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
}
/* add in texel */
lohi <<= 2;
lohi |= texel;
}
cc[1] = lohi;
}
}
Q_MOV32(hi, 9 | (vec[3][GCOMP] & 4) | ((vec[1][GCOMP] >> 1) & 2)); /* chroma = "1" */
for (j = 2 * 2 - 1; j >= 0; j--) {
for (i = 0; i < n_comp; i++) {
/* add in colors */
Q_SHL(hi, 5);
Q_OR32(hi, vec[j][i] >> 3);
}
}
((qword *)cc)[1] = hi;
}
static void
fxt1_quantize_MIXED0 (dword *cc,
byte input[N_TEXELS][MAX_COMP])
{
const int n_vect = 3; /* highest vector number in each microtile */
const int n_comp = 3; /* 3 components: R, G, B */
byte vec[2 * 2][MAX_COMP]; /* 2 extrema for each sub-block */
float b, iv[MAX_COMP]; /* interpolation vector */
int i, j, k;
qword hi; /* high quadword */
dword lohi, lolo; /* low quadword: hi dword, lo dword */
int minColL = 0, maxColL = 0;
int minColR = 0, maxColR = 0;
#if 0
int minSum;
int maxSum;
/* Our solution here is to find the darkest and brightest colors in
* the 4x4 tile and use those as the two representative colors.
* There are probably better algorithms to use (histogram-based).
*/
minSum = 2000; /* big enough */
maxSum = -1; /* small enough */
for (k = 0; k < N_TEXELS / 2; k++) {
int sum = 0;
for (i = 0; i < n_comp; i++) {
sum += input[k][i];
}
if (minSum > sum) {
minSum = sum;
minColL = k;
}
if (maxSum < sum) {
maxSum = sum;
maxColL = k;
}
}
minSum = 2000; /* big enough */
maxSum = -1; /* small enough */
for (; k < N_TEXELS; k++) {
int sum = 0;
for (i = 0; i < n_comp; i++) {
sum += input[k][i];
}
if (minSum > sum) {
minSum = sum;
minColR = k;
}
if (maxSum < sum) {
maxSum = sum;
maxColR = k;
}
}
#else
int minVal;
int maxVal;
int maxVarL = fxt1_variance(NULL, input, n_comp, N_TEXELS / 2);
int maxVarR = fxt1_variance(NULL, &input[N_TEXELS / 2], n_comp, N_TEXELS / 2);
/* Scan the channel with max variance for lo & hi
* and use those as the two representative colors.
*/
minVal = 2000; /* big enough */
maxVal = -1; /* small enough */
for (k = 0; k < N_TEXELS / 2; k++) {
int t = input[k][maxVarL];
if (minVal > t) {
minVal = t;
minColL = k;
}
if (maxVal < t) {
maxVal = t;
maxColL = k;
}
}
minVal = 2000; /* big enough */
maxVal = -1; /* small enough */
for (; k < N_TEXELS; k++) {
int t = input[k][maxVarR];
if (minVal > t) {
minVal = t;
minColR = k;
}
if (maxVal < t) {
maxVal = t;
maxColR = k;
}
}
#endif
/* left microtile */
cc[0] = 0;
for (i = 0; i < n_comp; i++) {
vec[0][i] = input[minColL][i];
vec[1][i] = input[maxColL][i];
}
if (minColL != maxColL) {
/* compute interpolation vector */
MAKEIVEC(n_vect, n_comp, iv, b, vec[0], vec[1]);
/* add in texels */
lolo = 0;
for (k = N_TEXELS / 2 - 1; k >= 0; k--) {
int texel;
/* interpolate color */
CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
/* add in texel */
lolo <<= 2;
lolo |= texel;
}
/* funky encoding for LSB of green */
if ((int)((lolo >> 1) & 1) != (((vec[1][GCOMP] ^ vec[0][GCOMP]) >> 2) & 1)) {
for (i = 0; i < n_comp; i++) {
vec[1][i] = input[minColL][i];
vec[0][i] = input[maxColL][i];
}
lolo = ~lolo;
}
cc[0] = lolo;
}
/* right microtile */
cc[1] = 0;
for (i = 0; i < n_comp; i++) {
vec[2][i] = input[minColR][i];
vec[3][i] = input[maxColR][i];
}
if (minColR != maxColR) {
/* compute interpolation vector */
MAKEIVEC(n_vect, n_comp, iv, b, vec[2], vec[3]);
/* add in texels */
lohi = 0;
for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) {
int texel;
/* interpolate color */
CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
/* add in texel */
lohi <<= 2;
lohi |= texel;
}
/* funky encoding for LSB of green */
if ((int)((lohi >> 1) & 1) != (((vec[3][GCOMP] ^ vec[2][GCOMP]) >> 2) & 1)) {
for (i = 0; i < n_comp; i++) {
vec[3][i] = input[minColR][i];
vec[2][i] = input[maxColR][i];
}
lohi = ~lohi;
}
cc[1] = lohi;
}
Q_MOV32(hi, 8 | (vec[3][GCOMP] & 4) | ((vec[1][GCOMP] >> 1) & 2)); /* chroma = "1" */
for (j = 2 * 2 - 1; j >= 0; j--) {
for (i = 0; i < n_comp; i++) {
/* add in colors */
Q_SHL(hi, 5);
Q_OR32(hi, vec[j][i] >> 3);
}
}
((qword *)cc)[1] = hi;
}
static void
fxt1_quantize (dword *cc, const byte *lines[], int comps)
{
int trualpha;
byte reord[N_TEXELS][MAX_COMP];
byte input[N_TEXELS][MAX_COMP];
int i, k, l;
if (comps == 3) {
/* make the whole block opaque */
memset(input, -1, sizeof(input));
}
/* 8 texels each line */
for (l = 0; l < 4; l++) {
for (k = 0; k < 4; k++) {
for (i = 0; i < comps; i++) {
input[k + l * 4][i] = *lines[l]++;
}
}
for (; k < 8; k++) {
for (i = 0; i < comps; i++) {
input[k + l * 4 + 12][i] = *lines[l]++;
}
}
}
/* block layout:
* 00, 01, 02, 03, 08, 09, 0a, 0b
* 10, 11, 12, 13, 18, 19, 1a, 1b
* 04, 05, 06, 07, 0c, 0d, 0e, 0f
* 14, 15, 16, 17, 1c, 1d, 1e, 1f
*/
/* [dBorca]
* stupidity flows forth from this
*/
l = N_TEXELS;
trualpha = 0;
if (comps == 4) {
/* skip all transparent black texels */
l = 0;
for (k = 0; k < N_TEXELS; k++) {
/* test all components against 0 */
if (!ISTBLACK(input[k])) {
/* texel is not transparent black */
COPY_4UBV(reord[l], input[k]);
if (reord[l][ACOMP] < (255 - ALPHA_TS)) {
/* non-opaque texel */
trualpha = !0;
}
l++;
}
}
}
#if 0
if (trualpha) {
fxt1_quantize_ALPHA0(cc, input, reord, l);
} else if (l == 0) {
cc[0] = cc[1] = cc[2] = -1;
cc[3] = 0;
} else if (l < N_TEXELS) {
fxt1_quantize_HI(cc, input, reord, l);
} else {
fxt1_quantize_CHROMA(cc, input);
}
(void)fxt1_quantize_ALPHA1;
(void)fxt1_quantize_MIXED1;
(void)fxt1_quantize_MIXED0;
#else
if (trualpha) {
fxt1_quantize_ALPHA1(cc, input);
} else if (l == 0) {
cc[0] = cc[1] = cc[2] = ~0UL;
cc[3] = 0;
} else if (l < N_TEXELS) {
fxt1_quantize_MIXED1(cc, input);
} else {
fxt1_quantize_MIXED0(cc, input);
}
(void)fxt1_quantize_ALPHA0;
(void)fxt1_quantize_HI;
(void)fxt1_quantize_CHROMA;
#endif
}
TAPI int TAPIENTRY
fxt1_encode (int width, int height, int comps,
const void *source, int srcRowStride,
void *dest, int destRowStride)
{
int x, y;
const byte *data;
dword *encoded = (dword *)dest;
void *newSource = NULL;
/* Replicate image if width is not M8 or height is not M4 */
if ((width & 7) | (height & 3)) {
int newWidth = (width + 7) & ~7;
int newHeight = (height + 3) & ~3;
newSource = malloc(comps * newWidth * newHeight * sizeof(byte *));
_mesa_upscale_teximage2d(width, height, newWidth, newHeight,
comps, (const byte *)source,
srcRowStride, (byte *)newSource);
source = newSource;
width = newWidth;
height = newHeight;
srcRowStride = comps * newWidth;
}
data = (const byte *)source;
destRowStride = (destRowStride - width * 2) / 4;
for (y = 0; y < height; y += 4) {
unsigned int offs = 0 + (y + 0) * srcRowStride;
for (x = 0; x < width; x += 8) {
const byte *lines[4];
lines[0] = &data[offs];
lines[1] = lines[0] + srcRowStride;
lines[2] = lines[1] + srcRowStride;
lines[3] = lines[2] + srcRowStride;
offs += 8 * comps;
fxt1_quantize(encoded, lines, comps);
/* 128 bits per 8x4 block */
encoded += 4;
}
encoded += destRowStride;
}
if (newSource != NULL) {
free(newSource);
}
return 0;
}
/***************************************************************************\
* FXT1 decoder
*
* The decoder is based on GL_3DFX_texture_compression_FXT1
* specification and serves as a concept for the encoder.
\***************************************************************************/
/* lookup table for scaling 5 bit colors up to 8 bits */
static const byte _rgb_scale_5[] = {
0, 8, 16, 25, 33, 41, 49, 58,
66, 74, 82, 90, 99, 107, 115, 123,
132, 140, 148, 156, 165, 173, 181, 189,
197, 206, 214, 222, 230, 239, 247, 255
};
/* lookup table for scaling 6 bit colors up to 8 bits */
static const byte _rgb_scale_6[] = {
0, 4, 8, 12, 16, 20, 24, 28,
32, 36, 40, 45, 49, 53, 57, 61,
65, 69, 73, 77, 81, 85, 89, 93,
97, 101, 105, 109, 113, 117, 121, 125,
130, 134, 138, 142, 146, 150, 154, 158,
162, 166, 170, 174, 178, 182, 186, 190,
194, 198, 202, 206, 210, 215, 219, 223,
227, 231, 235, 239, 243, 247, 251, 255
};
#define CC_SEL(cc, which) (((dword *)(cc))[(which) / 32] >> ((which) & 31))
#define UP5(c) _rgb_scale_5[(c) & 31]
#define UP6(c, b) _rgb_scale_6[(((c) & 31) << 1) | ((b) & 1)]
#define LERP(n, t, c0, c1) (((n) - (t)) * (c0) + (t) * (c1) + (n) / 2) / (n)
#define ZERO_4UBV(v) *((dword *)(v)) = 0
static void
fxt1_decode_1HI (const byte *code, int t, byte *rgba)
{
const dword *cc;
t *= 3;
cc = (const dword *)(code + t / 8);
t = (cc[0] >> (t & 7)) & 7;
if (t == 7) {
ZERO_4UBV(rgba);
} else {
cc = (const dword *)(code + 12);
if (t == 0) {
rgba[BCOMP] = UP5(CC_SEL(cc, 0));
rgba[GCOMP] = UP5(CC_SEL(cc, 5));
rgba[RCOMP] = UP5(CC_SEL(cc, 10));
} else if (t == 6) {
rgba[BCOMP] = UP5(CC_SEL(cc, 15));
rgba[GCOMP] = UP5(CC_SEL(cc, 20));
rgba[RCOMP] = UP5(CC_SEL(cc, 25));
} else {
rgba[BCOMP] = LERP(6, t, UP5(CC_SEL(cc, 0)), UP5(CC_SEL(cc, 15)));
rgba[GCOMP] = LERP(6, t, UP5(CC_SEL(cc, 5)), UP5(CC_SEL(cc, 20)));
rgba[RCOMP] = LERP(6, t, UP5(CC_SEL(cc, 10)), UP5(CC_SEL(cc, 25)));
}
rgba[ACOMP] = 255;
}
}
static void
fxt1_decode_1CHROMA (const byte *code, int t, byte *rgba)
{
const dword *cc;
dword kk;
cc = (const dword *)code;
if (t & 16) {
cc++;
t &= 15;
}
t = (cc[0] >> (t * 2)) & 3;
t *= 15;
cc = (const dword *)(code + 8 + t / 8);
kk = cc[0] >> (t & 7);
rgba[BCOMP] = UP5(kk);
rgba[GCOMP] = UP5(kk >> 5);
rgba[RCOMP] = UP5(kk >> 10);
rgba[ACOMP] = 255;
}
static void
fxt1_decode_1MIXED (const byte *code, int t, byte *rgba)
{
const dword *cc;
int col[2][3];
int glsb, selb;
cc = (const dword *)code;
if (t & 16) {
t &= 15;
t = (cc[1] >> (t * 2)) & 3;
/* col 2 */
col[0][BCOMP] = (*(const dword *)(code + 11)) >> 6;
col[0][GCOMP] = CC_SEL(cc, 99);
col[0][RCOMP] = CC_SEL(cc, 104);
/* col 3 */
col[1][BCOMP] = CC_SEL(cc, 109);
col[1][GCOMP] = CC_SEL(cc, 114);
col[1][RCOMP] = CC_SEL(cc, 119);
glsb = CC_SEL(cc, 126);
selb = CC_SEL(cc, 33);
} else {
t = (cc[0] >> (t * 2)) & 3;
/* col 0 */
col[0][BCOMP] = CC_SEL(cc, 64);
col[0][GCOMP] = CC_SEL(cc, 69);
col[0][RCOMP] = CC_SEL(cc, 74);
/* col 1 */
col[1][BCOMP] = CC_SEL(cc, 79);
col[1][GCOMP] = CC_SEL(cc, 84);
col[1][RCOMP] = CC_SEL(cc, 89);
glsb = CC_SEL(cc, 125);
selb = CC_SEL(cc, 1);
}
if (CC_SEL(cc, 124) & 1) {
/* alpha[0] == 1 */
if (t == 3) {
ZERO_4UBV(rgba);
} else {
if (t == 0) {
rgba[BCOMP] = UP5(col[0][BCOMP]);
rgba[GCOMP] = UP5(col[0][GCOMP]);
rgba[RCOMP] = UP5(col[0][RCOMP]);
} else if (t == 2) {
rgba[BCOMP] = UP5(col[1][BCOMP]);
rgba[GCOMP] = UP6(col[1][GCOMP], glsb);
rgba[RCOMP] = UP5(col[1][RCOMP]);
} else {
rgba[BCOMP] = (UP5(col[0][BCOMP]) + UP5(col[1][BCOMP])) / 2;
rgba[GCOMP] = (UP5(col[0][GCOMP]) + UP6(col[1][GCOMP], glsb)) / 2;
rgba[RCOMP] = (UP5(col[0][RCOMP]) + UP5(col[1][RCOMP])) / 2;
}
rgba[ACOMP] = 255;
}
} else {
/* alpha[0] == 0 */
if (t == 0) {
rgba[BCOMP] = UP5(col[0][BCOMP]);
rgba[GCOMP] = UP6(col[0][GCOMP], glsb ^ selb);
rgba[RCOMP] = UP5(col[0][RCOMP]);
} else if (t == 3) {
rgba[BCOMP] = UP5(col[1][BCOMP]);
rgba[GCOMP] = UP6(col[1][GCOMP], glsb);
rgba[RCOMP] = UP5(col[1][RCOMP]);
} else {
rgba[BCOMP] = LERP(3, t, UP5(col[0][BCOMP]), UP5(col[1][BCOMP]));
rgba[GCOMP] = LERP(3, t, UP6(col[0][GCOMP], glsb ^ selb),
UP6(col[1][GCOMP], glsb));
rgba[RCOMP] = LERP(3, t, UP5(col[0][RCOMP]), UP5(col[1][RCOMP]));
}
rgba[ACOMP] = 255;
}
}
static void
fxt1_decode_1ALPHA (const byte *code, int t, byte *rgba)
{
const dword *cc;
cc = (const dword *)code;
if (CC_SEL(cc, 124) & 1) {
/* lerp == 1 */
int col0[4];
if (t & 16) {
t &= 15;
t = (cc[1] >> (t * 2)) & 3;
/* col 2 */
col0[BCOMP] = (*(const dword *)(code + 11)) >> 6;
col0[GCOMP] = CC_SEL(cc, 99);
col0[RCOMP] = CC_SEL(cc, 104);
col0[ACOMP] = CC_SEL(cc, 119);
} else {
t = (cc[0] >> (t * 2)) & 3;
/* col 0 */
col0[BCOMP] = CC_SEL(cc, 64);
col0[GCOMP] = CC_SEL(cc, 69);
col0[RCOMP] = CC_SEL(cc, 74);
col0[ACOMP] = CC_SEL(cc, 109);
}
if (t == 0) {
rgba[BCOMP] = UP5(col0[BCOMP]);
rgba[GCOMP] = UP5(col0[GCOMP]);
rgba[RCOMP] = UP5(col0[RCOMP]);
rgba[ACOMP] = UP5(col0[ACOMP]);
} else if (t == 3) {
rgba[BCOMP] = UP5(CC_SEL(cc, 79));
rgba[GCOMP] = UP5(CC_SEL(cc, 84));
rgba[RCOMP] = UP5(CC_SEL(cc, 89));
rgba[ACOMP] = UP5(CC_SEL(cc, 114));
} else {
rgba[BCOMP] = LERP(3, t, UP5(col0[BCOMP]), UP5(CC_SEL(cc, 79)));
rgba[GCOMP] = LERP(3, t, UP5(col0[GCOMP]), UP5(CC_SEL(cc, 84)));
rgba[RCOMP] = LERP(3, t, UP5(col0[RCOMP]), UP5(CC_SEL(cc, 89)));
rgba[ACOMP] = LERP(3, t, UP5(col0[ACOMP]), UP5(CC_SEL(cc, 114)));
}
} else {
/* lerp == 0 */
if (t & 16) {
cc++;
t &= 15;
}
t = (cc[0] >> (t * 2)) & 3;
if (t == 3) {
ZERO_4UBV(rgba);
} else {
dword kk;
cc = (const dword *)code;
rgba[ACOMP] = UP5(cc[3] >> (t * 5 + 13));
t *= 15;
cc = (const dword *)(code + 8 + t / 8);
kk = cc[0] >> (t & 7);
rgba[BCOMP] = UP5(kk);
rgba[GCOMP] = UP5(kk >> 5);
rgba[RCOMP] = UP5(kk >> 10);
}
}
}
TAPI void TAPIENTRY
fxt1_decode_1 (const void *texture, int stride,
int i, int j, byte *rgba)
{
static void (*decode_1[]) (const byte *, int, byte *) = {
fxt1_decode_1HI, /* cc-high = "00?" */
fxt1_decode_1HI, /* cc-high = "00?" */
fxt1_decode_1CHROMA, /* cc-chroma = "010" */
fxt1_decode_1ALPHA, /* alpha = "011" */
fxt1_decode_1MIXED, /* mixed = "1??" */
fxt1_decode_1MIXED, /* mixed = "1??" */
fxt1_decode_1MIXED, /* mixed = "1??" */
fxt1_decode_1MIXED /* mixed = "1??" */
};
const byte *code = (const byte *)texture +
((j / 4) * (stride / 8) + (i / 8)) * 16;
int mode = CC_SEL(code, 125);
int t = i & 7;
if (t & 4) {
t += 12;
}
t += (j & 3) * 4;
decode_1[mode](code, t, rgba);
#if VERBOSE
{
extern int cc_chroma;
extern int cc_alpha;
extern int cc_high;
extern int cc_mixed;
static int *cctype[] = {
&cc_high,
&cc_high,
&cc_chroma,
&cc_alpha,
&cc_mixed,
&cc_mixed,
&cc_mixed,
&cc_mixed
};
(*cctype[mode])++;
}
#endif
}