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-rw-r--r--src/util/Makefile.sources3
-rw-r--r--src/util/rgtc.c61
-rw-r--r--src/util/rgtc.h39
-rw-r--r--src/util/texcompress_rgtc_tmp.h418
4 files changed, 520 insertions, 1 deletions
diff --git a/src/util/Makefile.sources b/src/util/Makefile.sources
index b99aa25e86e..c34475a8493 100644
--- a/src/util/Makefile.sources
+++ b/src/util/Makefile.sources
@@ -1,6 +1,7 @@
MESA_UTIL_FILES := \
hash_table.c \
- ralloc.c
+ ralloc.c \
+ rgtc.c
MESA_UTIL_GENERATED_FILES = \
format_srgb.c
diff --git a/src/util/rgtc.c b/src/util/rgtc.c
new file mode 100644
index 00000000000..6886ac07112
--- /dev/null
+++ b/src/util/rgtc.c
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2011 Red Hat Inc.
+ *
+ * block compression parts are:
+ * Copyright (C) 2004 Roland Scheidegger 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 (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 NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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.
+ *
+ * Author:
+ * Dave Airlie
+ */
+
+#include <inttypes.h>
+#include "macros.h"
+
+#include "rgtc.h"
+
+#define RGTC_DEBUG 0
+
+#define TAG(x) util_format_unsigned_##x
+
+#define TYPE unsigned char
+#define T_MIN 0
+#define T_MAX 0xff
+
+#include "texcompress_rgtc_tmp.h"
+
+#undef TAG
+#undef TYPE
+#undef T_MIN
+#undef T_MAX
+
+#define TAG(x) util_format_signed_##x
+#define TYPE signed char
+#define T_MIN (signed char)-128
+#define T_MAX (signed char)127
+
+#include "texcompress_rgtc_tmp.h"
+
+#undef TAG
+#undef TYPE
+#undef T_MIN
+#undef T_MAX
+
diff --git a/src/util/rgtc.h b/src/util/rgtc.h
new file mode 100644
index 00000000000..6bba9f2ec77
--- /dev/null
+++ b/src/util/rgtc.h
@@ -0,0 +1,39 @@
+/*
+ * Copyright © 2014 Red Hat
+ *
+ * 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 (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 NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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.
+ *
+ */
+
+#ifndef _RGTC_H
+#define _RGTC_H
+
+void util_format_unsigned_fetch_texel_rgtc(unsigned srcRowStride, const unsigned char *pixdata,
+ unsigned i, unsigned j, unsigned char *value, unsigned comps);
+
+void util_format_signed_fetch_texel_rgtc(unsigned srcRowStride, const signed char *pixdata,
+ unsigned i, unsigned j, signed char *value, unsigned comps);
+
+void util_format_unsigned_encode_rgtc_ubyte(unsigned char *blkaddr, unsigned char srccolors[4][4],
+ int numxpixels, int numypixels);
+
+void util_format_signed_encode_rgtc_ubyte(signed char *blkaddr, signed char srccolors[4][4],
+ int numxpixels, int numypixels);
+#endif /* _RGTC_H */
diff --git a/src/util/texcompress_rgtc_tmp.h b/src/util/texcompress_rgtc_tmp.h
new file mode 100644
index 00000000000..6bbae5eadfe
--- /dev/null
+++ b/src/util/texcompress_rgtc_tmp.h
@@ -0,0 +1,418 @@
+/*
+ * Copyright (C) 2011 Red Hat Inc.
+ *
+ * block compression parts are:
+ * Copyright (C) 2004 Roland Scheidegger 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 (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 NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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.
+ *
+ * Author:
+ * Dave Airlie
+ */
+
+/* included by texcompress_rgtc to define byte/ubyte compressors */
+
+void TAG(fetch_texel_rgtc)(unsigned srcRowStride, const TYPE *pixdata,
+ unsigned i, unsigned j, TYPE *value, unsigned comps)
+{
+ TYPE decode;
+ const TYPE *blksrc = (pixdata + ((srcRowStride + 3) / 4 * (j / 4) + (i / 4)) * 8 * comps);
+ const TYPE alpha0 = blksrc[0];
+ const TYPE alpha1 = blksrc[1];
+ const char bit_pos = ((j&3) * 4 + (i&3)) * 3;
+ const unsigned char acodelow = blksrc[2 + bit_pos / 8];
+ const unsigned char acodehigh = (3 + bit_pos / 8) < 8 ? blksrc[3 + bit_pos / 8] : 0;
+ const unsigned char code = (acodelow >> (bit_pos & 0x7) |
+ (acodehigh << (8 - (bit_pos & 0x7)))) & 0x7;
+
+ if (code == 0)
+ decode = alpha0;
+ else if (code == 1)
+ decode = alpha1;
+ else if (alpha0 > alpha1)
+ decode = ((alpha0 * (8 - code) + (alpha1 * (code - 1))) / 7);
+ else if (code < 6)
+ decode = ((alpha0 * (6 - code) + (alpha1 * (code - 1))) / 5);
+ else if (code == 6)
+ decode = T_MIN;
+ else
+ decode = T_MAX;
+
+ *value = decode;
+}
+
+static void TAG(write_rgtc_encoded_channel)(TYPE *blkaddr,
+ TYPE alphabase1,
+ TYPE alphabase2,
+ TYPE alphaenc[16])
+{
+ *blkaddr++ = alphabase1;
+ *blkaddr++ = alphabase2;
+ *blkaddr++ = alphaenc[0] | (alphaenc[1] << 3) | ((alphaenc[2] & 3) << 6);
+ *blkaddr++ = (alphaenc[2] >> 2) | (alphaenc[3] << 1) | (alphaenc[4] << 4) | ((alphaenc[5] & 1) << 7);
+ *blkaddr++ = (alphaenc[5] >> 1) | (alphaenc[6] << 2) | (alphaenc[7] << 5);
+ *blkaddr++ = alphaenc[8] | (alphaenc[9] << 3) | ((alphaenc[10] & 3) << 6);
+ *blkaddr++ = (alphaenc[10] >> 2) | (alphaenc[11] << 1) | (alphaenc[12] << 4) | ((alphaenc[13] & 1) << 7);
+ *blkaddr++ = (alphaenc[13] >> 1) | (alphaenc[14] << 2) | (alphaenc[15] << 5);
+}
+
+void TAG(encode_rgtc_ubyte)(TYPE *blkaddr, TYPE srccolors[4][4],
+ int numxpixels, int numypixels)
+{
+ TYPE alphabase[2], alphause[2];
+ short alphatest[2] = { 0 };
+ unsigned int alphablockerror1, alphablockerror2, alphablockerror3;
+ TYPE i, j, aindex, acutValues[7];
+ TYPE alphaenc1[16], alphaenc2[16], alphaenc3[16];
+ int alphaabsmin = 0, alphaabsmax = 0;
+ short alphadist;
+
+ /* find lowest and highest alpha value in block, alphabase[0] lowest, alphabase[1] highest */
+ alphabase[0] = T_MAX; alphabase[1] = T_MIN;
+ for (j = 0; j < numypixels; j++) {
+ for (i = 0; i < numxpixels; i++) {
+ if (srccolors[j][i] == T_MIN)
+ alphaabsmin = 1;
+ else if (srccolors[j][i] == T_MAX)
+ alphaabsmax = 1;
+ else {
+ if (srccolors[j][i] > alphabase[1])
+ alphabase[1] = srccolors[j][i];
+ if (srccolors[j][i] < alphabase[0])
+ alphabase[0] = srccolors[j][i];
+ }
+ }
+ }
+
+
+ if (((alphabase[0] > alphabase[1]) && !(alphaabsmin && alphaabsmax))
+ || (alphabase[0] == alphabase[1] && !alphaabsmin && !alphaabsmax)) { /* one color, either max or min */
+ /* shortcut here since it is a very common case (and also avoids later problems) */
+ /* could also thest for alpha0 == alpha1 (and not min/max), but probably not common, so don't bother */
+
+ *blkaddr++ = srccolors[0][0];
+ blkaddr++;
+ *blkaddr++ = 0;
+ *blkaddr++ = 0;
+ *blkaddr++ = 0;
+ *blkaddr++ = 0;
+ *blkaddr++ = 0;
+ *blkaddr++ = 0;
+#if RGTC_DEBUG
+ fprintf(stderr, "enc0 used\n");
+#endif
+ return;
+ }
+
+ /* find best encoding for alpha0 > alpha1 */
+ /* it's possible this encoding is better even if both alphaabsmin and alphaabsmax are true */
+ alphablockerror1 = 0x0;
+ alphablockerror2 = 0xffffffff;
+ alphablockerror3 = 0xffffffff;
+ if (alphaabsmin) alphause[0] = T_MIN;
+ else alphause[0] = alphabase[0];
+ if (alphaabsmax) alphause[1] = T_MAX;
+ else alphause[1] = alphabase[1];
+ /* calculate the 7 cut values, just the middle between 2 of the computed alpha values */
+ for (aindex = 0; aindex < 7; aindex++) {
+ /* don't forget here is always rounded down */
+ acutValues[aindex] = (alphause[0] * (2*aindex + 1) + alphause[1] * (14 - (2*aindex + 1))) / 14;
+ }
+
+ for (j = 0; j < numypixels; j++) {
+ for (i = 0; i < numxpixels; i++) {
+ /* maybe it's overkill to have the most complicated calculation just for the error
+ calculation which we only need to figure out if encoding1 or encoding2 is better... */
+ if (srccolors[j][i] > acutValues[0]) {
+ alphaenc1[4*j + i] = 0;
+ alphadist = srccolors[j][i] - alphause[1];
+ }
+ else if (srccolors[j][i] > acutValues[1]) {
+ alphaenc1[4*j + i] = 2;
+ alphadist = srccolors[j][i] - (alphause[1] * 6 + alphause[0] * 1) / 7;
+ }
+ else if (srccolors[j][i] > acutValues[2]) {
+ alphaenc1[4*j + i] = 3;
+ alphadist = srccolors[j][i] - (alphause[1] * 5 + alphause[0] * 2) / 7;
+ }
+ else if (srccolors[j][i] > acutValues[3]) {
+ alphaenc1[4*j + i] = 4;
+ alphadist = srccolors[j][i] - (alphause[1] * 4 + alphause[0] * 3) / 7;
+ }
+ else if (srccolors[j][i] > acutValues[4]) {
+ alphaenc1[4*j + i] = 5;
+ alphadist = srccolors[j][i] - (alphause[1] * 3 + alphause[0] * 4) / 7;
+ }
+ else if (srccolors[j][i] > acutValues[5]) {
+ alphaenc1[4*j + i] = 6;
+ alphadist = srccolors[j][i] - (alphause[1] * 2 + alphause[0] * 5) / 7;
+ }
+ else if (srccolors[j][i] > acutValues[6]) {
+ alphaenc1[4*j + i] = 7;
+ alphadist = srccolors[j][i] - (alphause[1] * 1 + alphause[0] * 6) / 7;
+ }
+ else {
+ alphaenc1[4*j + i] = 1;
+ alphadist = srccolors[j][i] - alphause[0];
+ }
+ alphablockerror1 += alphadist * alphadist;
+ }
+ }
+
+#if RGTC_DEBUG
+ for (i = 0; i < 16; i++) {
+ fprintf(stderr, "%d ", alphaenc1[i]);
+ }
+ fprintf(stderr, "cutVals ");
+ for (i = 0; i < 7; i++) {
+ fprintf(stderr, "%d ", acutValues[i]);
+ }
+ fprintf(stderr, "srcVals ");
+ for (j = 0; j < numypixels; j++) {
+ for (i = 0; i < numxpixels; i++) {
+ fprintf(stderr, "%d ", srccolors[j][i]);
+ }
+ }
+ fprintf(stderr, "\n");
+#endif
+
+ /* it's not very likely this encoding is better if both alphaabsmin and alphaabsmax
+ are false but try it anyway */
+ if (alphablockerror1 >= 32) {
+
+ /* don't bother if encoding is already very good, this condition should also imply
+ we have valid alphabase colors which we absolutely need (alphabase[0] <= alphabase[1]) */
+ alphablockerror2 = 0;
+ for (aindex = 0; aindex < 5; aindex++) {
+ /* don't forget here is always rounded down */
+ acutValues[aindex] = (alphabase[0] * (10 - (2*aindex + 1)) + alphabase[1] * (2*aindex + 1)) / 10;
+ }
+ for (j = 0; j < numypixels; j++) {
+ for (i = 0; i < numxpixels; i++) {
+ /* maybe it's overkill to have the most complicated calculation just for the error
+ calculation which we only need to figure out if encoding1 or encoding2 is better... */
+ if (srccolors[j][i] == T_MIN) {
+ alphaenc2[4*j + i] = 6;
+ alphadist = 0;
+ }
+ else if (srccolors[j][i] == T_MAX) {
+ alphaenc2[4*j + i] = 7;
+ alphadist = 0;
+ }
+ else if (srccolors[j][i] <= acutValues[0]) {
+ alphaenc2[4*j + i] = 0;
+ alphadist = srccolors[j][i] - alphabase[0];
+ }
+ else if (srccolors[j][i] <= acutValues[1]) {
+ alphaenc2[4*j + i] = 2;
+ alphadist = srccolors[j][i] - (alphabase[0] * 4 + alphabase[1] * 1) / 5;
+ }
+ else if (srccolors[j][i] <= acutValues[2]) {
+ alphaenc2[4*j + i] = 3;
+ alphadist = srccolors[j][i] - (alphabase[0] * 3 + alphabase[1] * 2) / 5;
+ }
+ else if (srccolors[j][i] <= acutValues[3]) {
+ alphaenc2[4*j + i] = 4;
+ alphadist = srccolors[j][i] - (alphabase[0] * 2 + alphabase[1] * 3) / 5;
+ }
+ else if (srccolors[j][i] <= acutValues[4]) {
+ alphaenc2[4*j + i] = 5;
+ alphadist = srccolors[j][i] - (alphabase[0] * 1 + alphabase[1] * 4) / 5;
+ }
+ else {
+ alphaenc2[4*j + i] = 1;
+ alphadist = srccolors[j][i] - alphabase[1];
+ }
+ alphablockerror2 += alphadist * alphadist;
+ }
+ }
+
+
+ /* skip this if the error is already very small
+ this encoding is MUCH better on average than #2 though, but expensive! */
+ if ((alphablockerror2 > 96) && (alphablockerror1 > 96)) {
+ short blockerrlin1 = 0;
+ short blockerrlin2 = 0;
+ TYPE nralphainrangelow = 0;
+ TYPE nralphainrangehigh = 0;
+ alphatest[0] = T_MAX;
+ alphatest[1] = T_MIN;
+ /* if we have large range it's likely there are values close to 0/255, try to map them to 0/255 */
+ for (j = 0; j < numypixels; j++) {
+ for (i = 0; i < numxpixels; i++) {
+ if ((srccolors[j][i] > alphatest[1]) && (srccolors[j][i] < (T_MAX -(alphabase[1] - alphabase[0]) / 28)))
+ alphatest[1] = srccolors[j][i];
+ if ((srccolors[j][i] < alphatest[0]) && (srccolors[j][i] > (alphabase[1] - alphabase[0]) / 28))
+ alphatest[0] = srccolors[j][i];
+ }
+ }
+ /* shouldn't happen too often, don't really care about those degenerated cases */
+ if (alphatest[1] <= alphatest[0]) {
+ alphatest[0] = T_MIN+1;
+ alphatest[1] = T_MAX-1;
+ }
+ for (aindex = 0; aindex < 5; aindex++) {
+ /* don't forget here is always rounded down */
+ acutValues[aindex] = (alphatest[0] * (10 - (2*aindex + 1)) + alphatest[1] * (2*aindex + 1)) / 10;
+ }
+
+ /* find the "average" difference between the alpha values and the next encoded value.
+ This is then used to calculate new base values.
+ Should there be some weighting, i.e. those values closer to alphatest[x] have more weight,
+ since they will see more improvement, and also because the values in the middle are somewhat
+ likely to get no improvement at all (because the base values might move in different directions)?
+ OTOH it would mean the values in the middle are even less likely to get an improvement
+ */
+ for (j = 0; j < numypixels; j++) {
+ for (i = 0; i < numxpixels; i++) {
+ if (srccolors[j][i] <= alphatest[0] / 2) {
+ }
+ else if (srccolors[j][i] > ((T_MAX + alphatest[1]) / 2)) {
+ }
+ else if (srccolors[j][i] <= acutValues[0]) {
+ blockerrlin1 += (srccolors[j][i] - alphatest[0]);
+ nralphainrangelow += 1;
+ }
+ else if (srccolors[j][i] <= acutValues[1]) {
+ blockerrlin1 += (srccolors[j][i] - (alphatest[0] * 4 + alphatest[1] * 1) / 5);
+ blockerrlin2 += (srccolors[j][i] - (alphatest[0] * 4 + alphatest[1] * 1) / 5);
+ nralphainrangelow += 1;
+ nralphainrangehigh += 1;
+ }
+ else if (srccolors[j][i] <= acutValues[2]) {
+ blockerrlin1 += (srccolors[j][i] - (alphatest[0] * 3 + alphatest[1] * 2) / 5);
+ blockerrlin2 += (srccolors[j][i] - (alphatest[0] * 3 + alphatest[1] * 2) / 5);
+ nralphainrangelow += 1;
+ nralphainrangehigh += 1;
+ }
+ else if (srccolors[j][i] <= acutValues[3]) {
+ blockerrlin1 += (srccolors[j][i] - (alphatest[0] * 2 + alphatest[1] * 3) / 5);
+ blockerrlin2 += (srccolors[j][i] - (alphatest[0] * 2 + alphatest[1] * 3) / 5);
+ nralphainrangelow += 1;
+ nralphainrangehigh += 1;
+ }
+ else if (srccolors[j][i] <= acutValues[4]) {
+ blockerrlin1 += (srccolors[j][i] - (alphatest[0] * 1 + alphatest[1] * 4) / 5);
+ blockerrlin2 += (srccolors[j][i] - (alphatest[0] * 1 + alphatest[1] * 4) / 5);
+ nralphainrangelow += 1;
+ nralphainrangehigh += 1;
+ }
+ else {
+ blockerrlin2 += (srccolors[j][i] - alphatest[1]);
+ nralphainrangehigh += 1;
+ }
+ }
+ }
+ /* shouldn't happen often, needed to avoid div by zero */
+ if (nralphainrangelow == 0) nralphainrangelow = 1;
+ if (nralphainrangehigh == 0) nralphainrangehigh = 1;
+ alphatest[0] = alphatest[0] + (blockerrlin1 / nralphainrangelow);
+#if RGTC_DEBUG
+ fprintf(stderr, "block err lin low %d, nr %d\n", blockerrlin1, nralphainrangelow);
+ fprintf(stderr, "block err lin high %d, nr %d\n", blockerrlin2, nralphainrangehigh);
+#endif
+ /* again shouldn't really happen often... */
+ if (alphatest[0] < T_MIN) {
+ alphatest[0] = T_MIN;
+ }
+ alphatest[1] = alphatest[1] + (blockerrlin2 / nralphainrangehigh);
+ if (alphatest[1] > T_MAX) {
+ alphatest[1] = T_MAX;
+ }
+
+ alphablockerror3 = 0;
+ for (aindex = 0; aindex < 5; aindex++) {
+ /* don't forget here is always rounded down */
+ acutValues[aindex] = (alphatest[0] * (10 - (2*aindex + 1)) + alphatest[1] * (2*aindex + 1)) / 10;
+ }
+ for (j = 0; j < numypixels; j++) {
+ for (i = 0; i < numxpixels; i++) {
+ /* maybe it's overkill to have the most complicated calculation just for the error
+ calculation which we only need to figure out if encoding1 or encoding2 is better... */
+ if (srccolors[j][i] <= alphatest[0] / 2) {
+ alphaenc3[4*j + i] = 6;
+ alphadist = srccolors[j][i];
+ }
+ else if (srccolors[j][i] > ((T_MAX + alphatest[1]) / 2)) {
+ alphaenc3[4*j + i] = 7;
+ alphadist = T_MAX - srccolors[j][i];
+ }
+ else if (srccolors[j][i] <= acutValues[0]) {
+ alphaenc3[4*j + i] = 0;
+ alphadist = srccolors[j][i] - alphatest[0];
+ }
+ else if (srccolors[j][i] <= acutValues[1]) {
+ alphaenc3[4*j + i] = 2;
+ alphadist = srccolors[j][i] - (alphatest[0] * 4 + alphatest[1] * 1) / 5;
+ }
+ else if (srccolors[j][i] <= acutValues[2]) {
+ alphaenc3[4*j + i] = 3;
+ alphadist = srccolors[j][i] - (alphatest[0] * 3 + alphatest[1] * 2) / 5;
+ }
+ else if (srccolors[j][i] <= acutValues[3]) {
+ alphaenc3[4*j + i] = 4;
+ alphadist = srccolors[j][i] - (alphatest[0] * 2 + alphatest[1] * 3) / 5;
+ }
+ else if (srccolors[j][i] <= acutValues[4]) {
+ alphaenc3[4*j + i] = 5;
+ alphadist = srccolors[j][i] - (alphatest[0] * 1 + alphatest[1] * 4) / 5;
+ }
+ else {
+ alphaenc3[4*j + i] = 1;
+ alphadist = srccolors[j][i] - alphatest[1];
+ }
+ alphablockerror3 += alphadist * alphadist;
+ }
+ }
+ }
+ }
+
+ /* write the alpha values and encoding back. */
+ if ((alphablockerror1 <= alphablockerror2) && (alphablockerror1 <= alphablockerror3)) {
+#if RGTC_DEBUG
+ if (alphablockerror1 > 96) fprintf(stderr, "enc1 used, error %d\n", alphablockerror1);
+ fprintf(stderr,"w1: min %d max %d au0 %d au1 %d\n",
+ T_MIN, T_MAX,
+ alphause[1], alphause[0]);
+#endif
+
+ TAG(write_rgtc_encoded_channel)( blkaddr, alphause[1], alphause[0], alphaenc1 );
+ }
+ else if (alphablockerror2 <= alphablockerror3) {
+#if RGTC_DEBUG
+ if (alphablockerror2 > 96) fprintf(stderr, "enc2 used, error %d\n", alphablockerror2);
+ fprintf(stderr,"w2: min %d max %d au0 %d au1 %d\n",
+ T_MIN, T_MAX,
+ alphabase[0], alphabase[1]);
+#endif
+
+ TAG(write_rgtc_encoded_channel)( blkaddr, alphabase[0], alphabase[1], alphaenc2 );
+ }
+ else {
+#if RGTC_DEBUG
+ fprintf(stderr, "enc3 used, error %d\n", alphablockerror3);
+ fprintf(stderr,"w3: min %d max %d au0 %d au1 %d\n",
+ T_MIN, T_MAX,
+ alphatest[0], alphatest[1]);
+#endif
+
+ TAG(write_rgtc_encoded_channel)( blkaddr, (TYPE)alphatest[0], (TYPE)alphatest[1], alphaenc3 );
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-15 07:42:47 +0000