diff options
Diffstat (limited to 'mesalib/src/mesa/main/texcompress_etc_tmp.h')
| -rw-r--r-- | mesalib/src/mesa/main/texcompress_etc_tmp.h | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/mesalib/src/mesa/main/texcompress_etc_tmp.h b/mesalib/src/mesa/main/texcompress_etc_tmp.h new file mode 100644 index 000000000..5c8c6decf --- /dev/null +++ b/mesalib/src/mesa/main/texcompress_etc_tmp.h @@ -0,0 +1,136 @@ +/* + * Copyright (C) 2011 LunarG, Inc. + * + * 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. + */ + +/* + * Included by texcompress_etc1 and gallium to define ETC1 decoding routines. + */ + +struct TAG(etc1_block) { + uint32_t pixel_indices; + int flipped; + const int *modifier_tables[2]; + UINT8_TYPE base_colors[2][3]; +}; + +static UINT8_TYPE +TAG(etc1_base_color_diff_hi)(UINT8_TYPE in) +{ + return (in & 0xf8) | (in >> 5); +} + +static UINT8_TYPE +TAG(etc1_base_color_diff_lo)(UINT8_TYPE in) +{ + static const int lookup[8] = { 0, 1, 2, 3, -4, -3, -2, -1 }; + + in = (in >> 3) + lookup[in & 0x7]; + + return (in << 3) | (in >> 2); +} + +static UINT8_TYPE +TAG(etc1_base_color_ind_hi)(UINT8_TYPE in) +{ + return (in & 0xf0) | ((in & 0xf0) >> 4); +} + +static UINT8_TYPE +TAG(etc1_base_color_ind_lo)(UINT8_TYPE in) +{ + return ((in & 0xf) << 4) | (in & 0xf); +} + +static UINT8_TYPE +TAG(etc1_clamp)(UINT8_TYPE base, int modifier) +{ + int tmp = (int) base + modifier; + + /* CLAMP(tmp, 0, 255) */ + return (UINT8_TYPE) ((tmp < 0) ? 0 : ((tmp > 255) ? 255 : tmp)); +} + +static const int TAG(etc1_modifier_tables)[8][4] = { + { 2, 8, -2, -8}, + { 5, 17, -5, -17}, + { 9, 29, -9, -29}, + { 13, 42, -13, -42}, + { 18, 60, -18, -60}, + { 24, 80, -24, -80}, + { 33, 106, -33, -106}, + { 47, 183, -47, -183} +}; + +static void +TAG(etc1_parse_block)(struct TAG(etc1_block) *block, const UINT8_TYPE *src) +{ + if (src[3] & 0x2) { + /* differential mode */ + block->base_colors[0][0] = (int) TAG(etc1_base_color_diff_hi)(src[0]); + block->base_colors[1][0] = (int) TAG(etc1_base_color_diff_lo)(src[0]); + block->base_colors[0][1] = (int) TAG(etc1_base_color_diff_hi)(src[1]); + block->base_colors[1][1] = (int) TAG(etc1_base_color_diff_lo)(src[1]); + block->base_colors[0][2] = (int) TAG(etc1_base_color_diff_hi)(src[2]); + block->base_colors[1][2] = (int) TAG(etc1_base_color_diff_lo)(src[2]); + } + else { + /* individual mode */ + block->base_colors[0][0] = (int) TAG(etc1_base_color_ind_hi)(src[0]); + block->base_colors[1][0] = (int) TAG(etc1_base_color_ind_lo)(src[0]); + block->base_colors[0][1] = (int) TAG(etc1_base_color_ind_hi)(src[1]); + block->base_colors[1][1] = (int) TAG(etc1_base_color_ind_lo)(src[1]); + block->base_colors[0][2] = (int) TAG(etc1_base_color_ind_hi)(src[2]); + block->base_colors[1][2] = (int) TAG(etc1_base_color_ind_lo)(src[2]); + } + + /* pick modifier tables */ + block->modifier_tables[0] = TAG(etc1_modifier_tables)[(src[3] >> 5) & 0x7]; + block->modifier_tables[1] = TAG(etc1_modifier_tables)[(src[3] >> 2) & 0x7]; + + block->flipped = (src[3] & 0x1); + + block->pixel_indices = + (src[4] << 24) | (src[5] << 16) | (src[6] << 8) | src[7]; +} + +static void +TAG(etc1_fetch_texel)(const struct TAG(etc1_block) *block, + int x, int y, UINT8_TYPE *dst) +{ + const UINT8_TYPE *base_color; + int modifier, bit, idx, blk; + + /* get pixel index */ + bit = y + x * 4; + idx = ((block->pixel_indices >> (15 + bit)) & 0x2) | + ((block->pixel_indices >> (bit)) & 0x1); + + /* get subblock */ + blk = (block->flipped) ? (y >= 2) : (x >= 2); + + base_color = block->base_colors[blk]; + modifier = block->modifier_tables[blk][idx]; + + dst[0] = TAG(etc1_clamp)(base_color[0], modifier); + dst[1] = TAG(etc1_clamp)(base_color[1], modifier); + dst[2] = TAG(etc1_clamp)(base_color[2], modifier); +} |