diff options
Diffstat (limited to 'mesalib/src/mesa/main/texcompress_rgtc.c')
| -rw-r--r-- | mesalib/src/mesa/main/texcompress_rgtc.c | 1122 |
1 files changed, 1122 insertions, 0 deletions
diff --git a/mesalib/src/mesa/main/texcompress_rgtc.c b/mesalib/src/mesa/main/texcompress_rgtc.c new file mode 100644 index 000000000..b7725f4a9 --- /dev/null +++ b/mesalib/src/mesa/main/texcompress_rgtc.c @@ -0,0 +1,1122 @@ +/* + * 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 + */ + +/** + * \file texcompress_rgtc.c + * GL_EXT_texture_compression_rgtc support. + */ + + +#include "glheader.h" +#include "imports.h" +#include "colormac.h" +#include "image.h" +#include "macros.h" +#include "mfeatures.h" +#include "mipmap.h" +#include "texcompress.h" +#include "texcompress_rgtc.h" +#include "texstore.h" + +#define RGTC_DEBUG 0 + +static void encode_rgtc_chan_u(GLubyte *blkaddr, GLubyte srccolors[4][4], + GLint numxpixels, GLint numypixels); +static void encode_rgtc_chan_s(GLbyte *blkaddr, GLbyte srccolors[4][4], + GLint numxpixels, GLint numypixels); + +static void extractsrc_u( GLubyte srcpixels[4][4], const GLchan *srcaddr, + GLint srcRowStride, GLint numxpixels, GLint numypixels, GLint comps) +{ + GLubyte i, j; + const GLchan *curaddr; + for (j = 0; j < numypixels; j++) { + curaddr = srcaddr + j * srcRowStride * comps; + for (i = 0; i < numxpixels; i++) { + srcpixels[j][i] = *curaddr / (CHAN_MAX / 255); + curaddr += comps; + } + } +} + +static void extractsrc_s( GLbyte srcpixels[4][4], const GLfloat *srcaddr, + GLint srcRowStride, GLint numxpixels, GLint numypixels, GLint comps) +{ + GLubyte i, j; + const GLfloat *curaddr; + for (j = 0; j < numypixels; j++) { + curaddr = srcaddr + j * srcRowStride * comps; + for (i = 0; i < numxpixels; i++) { + srcpixels[j][i] = FLOAT_TO_BYTE_TEX(*curaddr); + curaddr += comps; + } + } +} + + +GLboolean +_mesa_texstore_red_rgtc1(TEXSTORE_PARAMS) +{ + GLubyte *dst; + const GLint texWidth = dstRowStride * 4 / 8; /* a bit of a hack */ + const GLchan *tempImage = NULL; + int i, j; + int numxpixels, numypixels; + const void *srcaddr; + GLubyte srcpixels[4][4]; + GLubyte *blkaddr; + GLint dstRowDiff; + ASSERT(dstFormat == MESA_FORMAT_RED_RGTC1); + ASSERT(dstXoffset % 4 == 0); + ASSERT(dstYoffset % 4 == 0); + ASSERT(dstZoffset % 4 == 0); + (void) dstZoffset; + (void) dstImageOffsets; + + + tempImage = _mesa_make_temp_chan_image(ctx, dims, + baseInternalFormat, + _mesa_get_format_base_format(dstFormat), + srcWidth, srcHeight, srcDepth, + srcFormat, srcType, srcAddr, + srcPacking); + if (!tempImage) + return GL_FALSE; /* out of memory */ + + dst = _mesa_compressed_image_address(dstXoffset, dstYoffset, 0, + dstFormat, + texWidth, (GLubyte *) dstAddr); + + blkaddr = dst; + dstRowDiff = dstRowStride >= (srcWidth * 4) ? dstRowStride - (((srcWidth + 3) & ~3) * 4) : 0; + for (j = 0; j < srcHeight; j+=4) { + if (srcHeight > j + 3) numypixels = 4; + else numypixels = srcHeight - j; + srcaddr = tempImage + j * srcWidth; + for (i = 0; i < srcWidth; i += 4) { + if (srcWidth > i + 3) numxpixels = 4; + else numxpixels = srcWidth - i; + extractsrc_u(srcpixels, srcaddr, srcWidth, numxpixels, numypixels, 1); + encode_rgtc_chan_u(blkaddr, srcpixels, numxpixels, numypixels); + srcaddr += numxpixels; + blkaddr += 8; + } + blkaddr += dstRowDiff; + } + if (tempImage) + free((void *) tempImage); + + return GL_TRUE; +} + +GLboolean +_mesa_texstore_signed_red_rgtc1(TEXSTORE_PARAMS) +{ + GLbyte *dst; + const GLint texWidth = dstRowStride * 4 / 8; /* a bit of a hack */ + const GLfloat *tempImage = NULL; + int i, j; + int numxpixels, numypixels; + const GLfloat *srcaddr; + GLbyte srcpixels[4][4]; + GLbyte *blkaddr; + GLint dstRowDiff; + ASSERT(dstFormat == MESA_FORMAT_SIGNED_RED_RGTC1); + ASSERT(dstXoffset % 4 == 0); + ASSERT(dstYoffset % 4 == 0); + ASSERT(dstZoffset % 4 == 0); + (void) dstZoffset; + (void) dstImageOffsets; + + tempImage = _mesa_make_temp_float_image(ctx, dims, + baseInternalFormat, + _mesa_get_format_base_format(dstFormat), + srcWidth, srcHeight, srcDepth, + srcFormat, srcType, srcAddr, + srcPacking, 0x0); + if (!tempImage) + return GL_FALSE; /* out of memory */ + + dst = (GLbyte *)_mesa_compressed_image_address(dstXoffset, dstYoffset, 0, + dstFormat, + texWidth, (GLubyte *) dstAddr); + + blkaddr = dst; + dstRowDiff = dstRowStride >= (srcWidth * 4) ? dstRowStride - (((srcWidth + 3) & ~3) * 4) : 0; + for (j = 0; j < srcHeight; j+=4) { + if (srcHeight > j + 3) numypixels = 4; + else numypixels = srcHeight - j; + srcaddr = tempImage + j * srcWidth; + for (i = 0; i < srcWidth; i += 4) { + if (srcWidth > i + 3) numxpixels = 4; + else numxpixels = srcWidth - i; + extractsrc_s(srcpixels, srcaddr, srcWidth, numxpixels, numypixels, 1); + encode_rgtc_chan_s(blkaddr, srcpixels, numxpixels, numypixels); + srcaddr += numxpixels; + blkaddr += 8; + } + blkaddr += dstRowDiff; + } + if (tempImage) + free((void *) tempImage); + + return GL_TRUE; +} + +GLboolean +_mesa_texstore_rg_rgtc2(TEXSTORE_PARAMS) +{ + GLubyte *dst; + const GLint texWidth = dstRowStride * 4 / 16; /* a bit of a hack */ + const GLchan *tempImage = NULL; + int i, j; + int numxpixels, numypixels; + const void *srcaddr; + GLubyte srcpixels[4][4]; + GLubyte *blkaddr; + GLint dstRowDiff; + + ASSERT(dstFormat == MESA_FORMAT_RG_RGTC2); + ASSERT(dstXoffset % 4 == 0); + ASSERT(dstYoffset % 4 == 0); + ASSERT(dstZoffset % 4 == 0); + (void) dstZoffset; + (void) dstImageOffsets; + + tempImage = _mesa_make_temp_chan_image(ctx, dims, + baseInternalFormat, + _mesa_get_format_base_format(dstFormat), + srcWidth, srcHeight, srcDepth, + srcFormat, srcType, srcAddr, + srcPacking); + if (!tempImage) + return GL_FALSE; /* out of memory */ + + dst = _mesa_compressed_image_address(dstXoffset, dstYoffset, 0, + dstFormat, + texWidth, (GLubyte *) dstAddr); + + blkaddr = dst; + dstRowDiff = dstRowStride >= (srcWidth * 8) ? dstRowStride - (((srcWidth + 7) & ~7) * 8) : 0; + for (j = 0; j < srcHeight; j+=4) { + if (srcHeight > j + 3) numypixels = 4; + else numypixels = srcHeight - j; + srcaddr = tempImage + j * srcWidth * 2; + for (i = 0; i < srcWidth; i += 4) { + if (srcWidth > i + 3) numxpixels = 4; + else numxpixels = srcWidth - i; + extractsrc_u(srcpixels, srcaddr, srcWidth, numxpixels, numypixels, 2); + encode_rgtc_chan_u(blkaddr, srcpixels, numxpixels, numypixels); + + blkaddr += 8; + extractsrc_u(srcpixels, (GLchan *)srcaddr + 1, srcWidth, numxpixels, numypixels, 2); + encode_rgtc_chan_u(blkaddr, srcpixels, numxpixels, numypixels); + + blkaddr += 8; + + srcaddr += numxpixels * 2; + } + blkaddr += dstRowDiff; + } + if (tempImage) + free((void *) tempImage); + + return GL_TRUE; +} + +GLboolean +_mesa_texstore_signed_rg_rgtc2(TEXSTORE_PARAMS) +{ + GLbyte *dst; + const GLint texWidth = dstRowStride * 4 / 16; /* a bit of a hack */ + const GLfloat *tempImage = NULL; + int i, j; + int numxpixels, numypixels; + const GLfloat *srcaddr; + GLbyte srcpixels[4][4]; + GLbyte *blkaddr; + GLint dstRowDiff; + + ASSERT(dstFormat == MESA_FORMAT_SIGNED_RG_RGTC2); + ASSERT(dstXoffset % 4 == 0); + ASSERT(dstYoffset % 4 == 0); + ASSERT(dstZoffset % 4 == 0); + (void) dstZoffset; + (void) dstImageOffsets; + + tempImage = _mesa_make_temp_float_image(ctx, dims, + baseInternalFormat, + _mesa_get_format_base_format(dstFormat), + srcWidth, srcHeight, srcDepth, + srcFormat, srcType, srcAddr, + srcPacking, 0x0); + if (!tempImage) + return GL_FALSE; /* out of memory */ + + dst = (GLbyte *)_mesa_compressed_image_address(dstXoffset, dstYoffset, 0, + dstFormat, + texWidth, (GLubyte *) dstAddr); + + blkaddr = dst; + dstRowDiff = dstRowStride >= (srcWidth * 8) ? dstRowStride - (((srcWidth + 7) & ~7) * 8) : 0; + for (j = 0; j < srcHeight; j += 4) { + if (srcHeight > j + 3) numypixels = 4; + else numypixels = srcHeight - j; + srcaddr = tempImage + j * srcWidth * 2; + for (i = 0; i < srcWidth; i += 4) { + if (srcWidth > i + 3) numxpixels = 4; + else numxpixels = srcWidth - i; + + extractsrc_s(srcpixels, srcaddr, srcWidth, numxpixels, numypixels, 2); + encode_rgtc_chan_s(blkaddr, srcpixels, numxpixels, numypixels); + blkaddr += 8; + + extractsrc_s(srcpixels, srcaddr + 1, srcWidth, numxpixels, numypixels, 2); + encode_rgtc_chan_s(blkaddr, srcpixels, numxpixels, numypixels); + blkaddr += 8; + + srcaddr += numxpixels * 2; + + } + blkaddr += dstRowDiff; + } + if (tempImage) + free((void *) tempImage); + + return GL_TRUE; +} + +static void _fetch_texel_rgtc_u(GLint srcRowStride, const GLubyte *pixdata, + GLint i, GLint j, GLchan *value, int comps) +{ + GLchan decode; + const GLubyte *blksrc = (pixdata + ((srcRowStride + 3) / 4 * (j / 4) + (i / 4)) * 8 * comps); + const GLubyte alpha0 = blksrc[0]; + const GLubyte alpha1 = blksrc[1]; + const GLubyte bit_pos = ((j&3) * 4 + (i&3)) * 3; + const GLubyte acodelow = blksrc[2 + bit_pos / 8]; + const GLubyte acodehigh = blksrc[3 + bit_pos / 8]; + const GLubyte code = (acodelow >> (bit_pos & 0x7) | + (acodehigh << (8 - (bit_pos & 0x7)))) & 0x7; + + if (code == 0) + decode = UBYTE_TO_CHAN( alpha0 ); + else if (code == 1) + decode = UBYTE_TO_CHAN( alpha1 ); + else if (alpha0 > alpha1) + decode = UBYTE_TO_CHAN( ((alpha0 * (8 - code) + (alpha1 * (code - 1))) / 7) ); + else if (code < 6) + decode = UBYTE_TO_CHAN( ((alpha0 * (6 - code) + (alpha1 * (code - 1))) / 5) ); + else if (code == 6) + decode = 0; + else + decode = CHAN_MAX; + + *value = decode; +} + + +static void _fetch_texel_rgtc_s(GLint srcRowStride, const GLbyte *pixdata, + GLint i, GLint j, GLbyte *value, int comps) +{ + GLbyte decode; + const GLbyte *blksrc = (pixdata + ((srcRowStride + 3) / 4 * (j / 4) + (i / 4)) * 8 * comps); + const GLbyte alpha0 = blksrc[0]; + const GLbyte alpha1 = blksrc[1]; + const GLbyte bit_pos = ((j&3) * 4 + (i&3)) * 3; + const GLbyte acodelow = blksrc[2 + bit_pos / 8]; + const GLbyte acodehigh = blksrc[3 + bit_pos / 8]; + const GLbyte 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 = -128; + else + decode = 127; + + *value = decode; +} + +void +_mesa_fetch_texel_2d_f_red_rgtc1(const struct gl_texture_image *texImage, + GLint i, GLint j, GLint k, GLfloat *texel) +{ + GLchan red; + _fetch_texel_rgtc_u(texImage->RowStride, (GLubyte *)(texImage->Data), + i, j, &red, 1); + texel[RCOMP] = CHAN_TO_FLOAT(red); + texel[GCOMP] = 0.0; + texel[BCOMP] = 0.0; + texel[ACOMP] = 1.0; +} + +void +_mesa_fetch_texel_2d_f_signed_red_rgtc1(const struct gl_texture_image *texImage, + GLint i, GLint j, GLint k, GLfloat *texel) +{ + GLbyte red; + _fetch_texel_rgtc_s(texImage->RowStride, (GLbyte *)(texImage->Data), + i, j, &red, 1); + texel[RCOMP] = BYTE_TO_FLOAT_TEX(red); + texel[GCOMP] = 0.0; + texel[BCOMP] = 0.0; + texel[ACOMP] = 1.0; +} + +void +_mesa_fetch_texel_2d_f_rg_rgtc2(const struct gl_texture_image *texImage, + GLint i, GLint j, GLint k, GLfloat *texel) +{ + GLchan red, green; + _fetch_texel_rgtc_u(texImage->RowStride, (GLubyte *)(texImage->Data), + i, j, &red, 2); + _fetch_texel_rgtc_u(texImage->RowStride, (GLubyte *)(texImage->Data) + 8, + i, j, &green, 2); + texel[RCOMP] = CHAN_TO_FLOAT(red); + texel[GCOMP] = CHAN_TO_FLOAT(green); + texel[BCOMP] = 0.0; + texel[ACOMP] = 1.0; +} + +void +_mesa_fetch_texel_2d_f_signed_rg_rgtc2(const struct gl_texture_image *texImage, + GLint i, GLint j, GLint k, GLfloat *texel) +{ + GLbyte red, green; + _fetch_texel_rgtc_s(texImage->RowStride, (GLbyte *)(texImage->Data), + i, j, &red, 2); + _fetch_texel_rgtc_s(texImage->RowStride, (GLbyte *)(texImage->Data) + 8, + i, j, &green, 2); + texel[RCOMP] = BYTE_TO_FLOAT_TEX(red); + texel[GCOMP] = BYTE_TO_FLOAT_TEX(green); + texel[BCOMP] = 0.0; + texel[ACOMP] = 1.0; +} + +static void write_rgtc_encoded_channel(GLubyte *blkaddr, + GLubyte alphabase1, + GLubyte alphabase2, + GLubyte 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); +} + +static void encode_rgtc_chan_u(GLubyte *blkaddr, GLubyte srccolors[4][4], + GLint numxpixels, GLint numypixels) +{ + GLubyte alphabase[2], alphause[2]; + GLshort alphatest[2] = { 0 }; + GLuint alphablockerror1, alphablockerror2, alphablockerror3; + GLubyte i, j, aindex, acutValues[7]; + GLubyte alphaenc1[16], alphaenc2[16], alphaenc3[16]; + GLboolean alphaabsmin = GL_FALSE; + GLboolean alphaabsmax = GL_FALSE; + GLshort alphadist; + + /* find lowest and highest alpha value in block, alphabase[0] lowest, alphabase[1] highest */ + alphabase[0] = 0xff; alphabase[1] = 0x0; + for (j = 0; j < numypixels; j++) { + for (i = 0; i < numxpixels; i++) { + if (srccolors[j][i] == 0) + alphaabsmin = GL_TRUE; + else if (srccolors[j][i] == 255) + alphaabsmax = GL_TRUE; + 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)) { /* one color, either max or min */ + /* shortcut here since it is a very common case (and also avoids later problems) */ + /* || (alphabase[0] == alphabase[1] && !alphaabsmin && !alphaabsmax) */ + /* 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] = 0; + else alphause[0] = alphabase[0]; + if (alphaabsmax) alphause[1] = 255; + 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 < 8; 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] == 0) { + alphaenc2[4*j + i] = 6; + alphadist = 0; + } + else if (srccolors[j][i] == 255) { + 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)) { + GLshort blockerrlin1 = 0; + GLshort blockerrlin2 = 0; + GLubyte nralphainrangelow = 0; + GLubyte nralphainrangehigh = 0; + alphatest[0] = 0xff; + alphatest[1] = 0x0; + /* 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] < (255 -(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] = 1; + alphatest[1] = 254; + } + 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] > ((255 + 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] < 0) { + alphatest[0] = 0; + } + alphatest[1] = alphatest[1] + (blockerrlin2 / nralphainrangehigh); + if (alphatest[1] > 255) { + alphatest[1] = 255; + } + + 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] > ((255 + alphatest[1]) / 2)) { + alphaenc3[4*j + i] = 7; + alphadist = 255 - 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); +#endif + 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); +#endif + write_rgtc_encoded_channel( blkaddr, alphabase[0], alphabase[1], alphaenc2 ); + } + else { +#if RGTC_DEBUG + fprintf(stderr, "enc3 used, error %d\n", alphablockerror3); +#endif + write_rgtc_encoded_channel( blkaddr, (GLubyte)alphatest[0], (GLubyte)alphatest[1], alphaenc3 ); + } +} + + +static void write_rgtc_encoded_channel_s(GLbyte *blkaddr, + GLbyte alphabase1, + GLbyte alphabase2, + GLbyte 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); +} + +static void encode_rgtc_chan_s(GLbyte *blkaddr, GLbyte srccolors[4][4], + GLint numxpixels, GLint numypixels) +{ + GLbyte alphabase[2], alphause[2]; + GLshort alphatest[2] = { 0 }; + GLuint alphablockerror1, alphablockerror2, alphablockerror3; + GLbyte i, j, aindex, acutValues[7]; + GLbyte alphaenc1[16], alphaenc2[16], alphaenc3[16]; + GLboolean alphaabsmin = GL_FALSE; + GLboolean alphaabsmax = GL_FALSE; + GLshort alphadist; + + /* find lowest and highest alpha value in block, alphabase[0] lowest, alphabase[1] highest */ + alphabase[0] = 0xff; alphabase[1] = 0x0; + for (j = 0; j < numypixels; j++) { + for (i = 0; i < numxpixels; i++) { + if (srccolors[j][i] == 0) + alphaabsmin = GL_TRUE; + else if (srccolors[j][i] == 255) + alphaabsmax = GL_TRUE; + 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)) { /* one color, either max or min */ + /* shortcut here since it is a very common case (and also avoids later problems) */ + /* || (alphabase[0] == alphabase[1] && !alphaabsmin && !alphaabsmax) */ + /* 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] = 0; + else alphause[0] = alphabase[0]; + if (alphaabsmax) alphause[1] = 255; + 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 < 8; 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] == 0) { + alphaenc2[4*j + i] = 6; + alphadist = 0; + } + else if (srccolors[j][i] == 255) { + 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)) { + GLshort blockerrlin1 = 0; + GLshort blockerrlin2 = 0; + GLubyte nralphainrangelow = 0; + GLubyte nralphainrangehigh = 0; + alphatest[0] = 0xff; + alphatest[1] = 0x0; + /* 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] < (255 -(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] = 1; + alphatest[1] = 254; + } + 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] > ((255 + 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] < 0) { + alphatest[0] = 0; + } + alphatest[1] = alphatest[1] + (blockerrlin2 / nralphainrangehigh); + if (alphatest[1] > 255) { + alphatest[1] = 255; + } + + 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] > ((255 + alphatest[1]) / 2)) { + alphaenc3[4*j + i] = 7; + alphadist = 255 - 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); +#endif + write_rgtc_encoded_channel_s( blkaddr, alphause[1], alphause[0], alphaenc1 ); + } + else if (alphablockerror2 <= alphablockerror3) { +#if RGTC_DEBUG + if (alphablockerror2 > 96) fprintf(stderr, "enc2 used, error %d\n", alphablockerror2); +#endif + write_rgtc_encoded_channel_s( blkaddr, alphabase[0], alphabase[1], alphaenc2 ); + } + else { +#if RGTC_DEBUG + fprintf(stderr, "enc3 used, error %d\n", alphablockerror3); +#endif + write_rgtc_encoded_channel_s( blkaddr, (GLubyte)alphatest[0], (GLubyte)alphatest[1], alphaenc3 ); + } +} |