1 /* 2 * Copyright (C) 2011 LunarG, Inc. 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 21 * DEALINGS IN THE SOFTWARE. 22 */ 23 24 /** 25 * \file texcompress_etc.c 26 * GL_OES_compressed_ETC1_RGB8_texture support. 27 */ 28 29 30 #include "mfeatures.h" 31 #include "texcompress.h" 32 #include "texcompress_etc.h" 33 #include "texstore.h" 34 #include "macros.h" 35 #include "swrast/s_context.h" 36 37 GLboolean 38 _mesa_texstore_etc1_rgb8(TEXSTORE_PARAMS) 39 { 40 /* GL_ETC1_RGB8_OES is only valid in glCompressedTexImage2D */ 41 ASSERT(0); 42 43 return GL_FALSE; 44 } 45 46 /* define etc1_parse_block and etc. */ 47 #define UINT8_TYPE GLubyte 48 #define TAG(x) x 49 #include "texcompress_etc_tmp.h" 50 #undef TAG 51 #undef UINT8_TYPE 52 53 void 54 _mesa_fetch_texel_2d_f_etc1_rgb8(const struct swrast_texture_image *texImage, 55 GLint i, GLint j, GLint k, GLfloat *texel) 56 { 57 struct etc1_block block; 58 GLubyte dst[3]; 59 const GLubyte *src; 60 61 src = (const GLubyte *) texImage->Map + 62 (((texImage->RowStride + 3) / 4) * (j / 4) + (i / 4)) * 8; 63 64 etc1_parse_block(&block, src); 65 etc1_fetch_texel(&block, i % 4, j % 4, dst); 66 67 texel[RCOMP] = UBYTE_TO_FLOAT(dst[0]); 68 texel[GCOMP] = UBYTE_TO_FLOAT(dst[1]); 69 texel[BCOMP] = UBYTE_TO_FLOAT(dst[2]); 70 texel[ACOMP] = 1.0f; 71 } 72 73 /** 74 * Decode texture data in format `MESA_FORMAT_ETC1_RGB8` to 75 * `MESA_FORMAT_ABGR8888`. 76 * 77 * The size of the source data must be a multiple of the ETC1 block size, 78 * which is 8, even if the texture image's dimensions are not aligned to 4. 79 * From the GL_OES_compressed_ETC1_RGB8_texture spec: 80 * The texture is described as a number of 4x4 pixel blocks. If the 81 * texture (or a particular mip-level) is smaller than 4 pixels in 82 * any dimension (such as a 2x2 or a 8x1 texture), the texture is 83 * found in the upper left part of the block(s), and the rest of the 84 * pixels are not used. For instance, a texture of size 4x2 will be 85 * placed in the upper half of a 4x4 block, and the lower half of the 86 * pixels in the block will not be accessed. 87 * 88 * \param src_width in pixels 89 * \param src_height in pixels 90 * \param dst_stride in bytes 91 */ 92 void 93 _mesa_etc1_unpack_rgba8888(uint8_t *dst_row, 94 unsigned dst_stride, 95 const uint8_t *src_row, 96 unsigned src_stride, 97 unsigned src_width, 98 unsigned src_height) 99 { 100 etc1_unpack_rgba8888(dst_row, dst_stride, 101 src_row, src_stride, 102 src_width, src_height); 103 } 104
