src/mesa/main/texcompress.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  6.5.1
   4  *
   5  * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
   6  * Copyright (c) 2008 VMware, Inc.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included
  16  * in all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  21  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  22  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  23  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  24  */
  25
  26
  27 /**
  28  * \file texcompress.c
  29  * Helper functions for texture compression.
  30  */
  31
  32
  33 #include "glheader.h"
  34 #include "imports.h"
  35 #include "colormac.h"
  36 #include "context.h"
  37 #include "formats.h"
  38 #include "image.h"
  39 #include "mipmap.h"
  40 #include "texcompress.h"
  41 #include "texstore.h"
  42
  43
  44 /**
  45  * Return list of (and count of) all specific texture compression
  46  * formats that are supported.
  47  *
  48  * \param ctx  the GL context
  49  * \param formats  the resulting format list (may be NULL).
  50  * \param all  if true return all formats, even those with  some kind
  51  *             of restrictions/limitations (See GL_ARB_texture_compression
  52  *             spec for more info).
  53  *
  54  * \return number of formats.
  55  */
  56 GLuint
  57 _mesa_get_compressed_formats(GLcontext *ctx, GLint *formats, GLboolean all)
  58 {
  59    GLuint n = 0;
  60    if (ctx->Extensions.TDFX_texture_compression_FXT1) {
  61       if (formats) {
  62          formats[n++] = GL_COMPRESSED_RGB_FXT1_3DFX;
  63          formats[n++] = GL_COMPRESSED_RGBA_FXT1_3DFX;
  64       }
  65       else {
  66          n += 2;
  67       }
  68    }
  69    if (ctx->Extensions.EXT_texture_compression_s3tc) {
  70       if (formats) {
  71          formats[n++] = GL_COMPRESSED_RGB_S3TC_DXT1_EXT;
  72          /* This format has some restrictions/limitations and so should
  73           * not be returned via the GL_COMPRESSED_TEXTURE_FORMATS query.
  74           * Specifically, all transparent pixels become black.  NVIDIA
  75           * omits this format too.
  76           */
  77          if (all)
  78              formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT1_EXT;
  79          formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT3_EXT;
  80          formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT5_EXT;
  81       }
  82       else {
  83          n += 3;
  84          if (all)
  85              n += 1;
  86       }
  87    }
  88    if (ctx->Extensions.S3_s3tc) {
  89       if (formats) {
  90          formats[n++] = GL_RGB_S3TC;
  91          formats[n++] = GL_RGB4_S3TC;
  92          formats[n++] = GL_RGBA_S3TC;
  93          formats[n++] = GL_RGBA4_S3TC;
  94       }
  95       else {
  96          n += 4;
  97       }
  98    }
  99 #if FEATURE_EXT_texture_sRGB
 100    if (ctx->Extensions.EXT_texture_sRGB) {
 101       if (formats) {
 102          formats[n++] = GL_COMPRESSED_SRGB_S3TC_DXT1_EXT;
 103          formats[n++] = GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT;
 104          formats[n++] = GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT;
 105          formats[n++] = GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT;
 106       }
 107       else {
 108          n += 4;
 109       }
 110    }
 111 #endif /* FEATURE_EXT_texture_sRGB */
 112    return n;
 113 }
 114
 115
 116
 117 /**
 118  * Return number of bytes needed to store a texture of the given size
 119  * using the specified (compressed?) format.
 120  * This is called via the ctx->Driver.CompressedTextureSize function,
 121  * unless a device driver overrides it.  A driver might override this
 122  * if it needs to use an unusual or padded texture memory layout.
 123  *
 124  * \param width texture width in texels.
 125  * \param height texture height in texels.
 126  * \param depth texture depth in texels.
 127  * \param mesaFormat  one of the MESA_FORMAT_* compressed formats
 128  *
 129  * \return size in bytes, or zero if bad format
 130  */
 131 GLuint
 132 _mesa_compressed_texture_size( GLcontext *ctx,
 133                                GLsizei width, GLsizei height, GLsizei depth,
 134                                gl_format mesaFormat )
 135 {
 136    return _mesa_format_image_size(mesaFormat, width, height, depth);
 137 }
 138
 139
 140 /**
 141  * As above, but format is specified by a GLenum (GL_COMPRESSED_*) token.
 142  *
 143  * Note: This function CAN NOT return a padded hardware texture size.
 144  * That's why we don't call the ctx->Driver.CompressedTextureSize() function.
 145  *
 146  * We use this function to validate the <imageSize> parameter
 147  * of glCompressedTex[Sub]Image1/2/3D(), which must be an exact match.
 148  */
 149 GLuint
 150 _mesa_compressed_texture_size_glenum(GLcontext *ctx,
 151                                      GLsizei width, GLsizei height,
 152                                      GLsizei depth, GLenum glformat)
 153 {
 154    gl_format mesaFormat;
 155
 156    switch (glformat) {
 157 #if FEATURE_texture_fxt1
 158    case GL_COMPRESSED_RGB_FXT1_3DFX:
 159       mesaFormat = MESA_FORMAT_RGB_FXT1;
 160       break;
 161    case GL_COMPRESSED_RGBA_FXT1_3DFX:
 162       mesaFormat = MESA_FORMAT_RGBA_FXT1;
 163       break;
 164 #endif
 165 #if FEATURE_texture_s3tc
 166    case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
 167    case GL_RGB_S3TC:
 168       mesaFormat = MESA_FORMAT_RGB_DXT1;
 169       break;
 170    case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
 171    case GL_RGB4_S3TC:
 172       mesaFormat = MESA_FORMAT_RGBA_DXT1;
 173       break;
 174    case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
 175    case GL_RGBA_S3TC:
 176       mesaFormat = MESA_FORMAT_RGBA_DXT3;
 177       break;
 178    case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
 179    case GL_RGBA4_S3TC:
 180       mesaFormat = MESA_FORMAT_RGBA_DXT5;
 181       break;
 182 #if FEATURE_EXT_texture_sRGB
 183    case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:
 184       mesaFormat = MESA_FORMAT_SRGB_DXT1;
 185       break;
 186    case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:
 187       mesaFormat = MESA_FORMAT_SRGBA_DXT1;
 188       break;
 189    case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:
 190       mesaFormat = MESA_FORMAT_SRGBA_DXT3;
 191       break;
 192    case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:
 193       mesaFormat = MESA_FORMAT_SRGBA_DXT5;
 194       break;
 195 #endif
 196 #endif
 197    default:
 198       return 0;
 199    }
 200
 201    return _mesa_format_image_size(mesaFormat, width, height, depth);
 202 }
 203
 204
 205 /*
 206  * Compute the bytes per row in a compressed texture image.
 207  * We use this for computing the destination address for sub-texture updates.
 208  * \param mesaFormat  one of the MESA_FORMAT_* compressed formats
 209  * \param width  image width in pixels
 210  * \return stride, in bytes, between rows for compressed image
 211  */
 212 GLint
 213 _mesa_compressed_row_stride(gl_format mesaFormat, GLsizei width)
 214 {
 215    GLint stride;
 216
 217    switch (mesaFormat) {
 218 #if FEATURE_texture_fxt1
 219    case MESA_FORMAT_RGB_FXT1:
 220    case MESA_FORMAT_RGBA_FXT1:
 221       stride = ((width + 7) / 8) * 16; /* 16 bytes per 8x4 tile */
 222       break;
 223 #endif
 224 #if FEATURE_texture_s3tc
 225    case MESA_FORMAT_RGB_DXT1:
 226    case MESA_FORMAT_RGBA_DXT1:
 227 #if FEATURE_EXT_texture_sRGB
 228    case MESA_FORMAT_SRGB_DXT1:
 229    case MESA_FORMAT_SRGBA_DXT1:
 230 #endif
 231       stride = ((width + 3) / 4) * 8; /* 8 bytes per 4x4 tile */
 232       break;
 233    case MESA_FORMAT_RGBA_DXT3:
 234    case MESA_FORMAT_RGBA_DXT5:
 235 #if FEATURE_EXT_texture_sRGB
 236    case MESA_FORMAT_SRGBA_DXT3:
 237    case MESA_FORMAT_SRGBA_DXT5:
 238 #endif
 239       stride = ((width + 3) / 4) * 16; /* 16 bytes per 4x4 tile */
 240       break;
 241 #endif
 242    default:
 243       _mesa_problem(NULL, "bad mesaFormat in _mesa_compressed_row_stride");
 244       return 0;
 245    }
 246
 247    assert(stride == _mesa_format_row_stride(mesaFormat, width));
 248
 249    return stride;
 250 }
 251
 252
 253 /*
 254  * Return the address of the pixel at (col, row, img) in a
 255  * compressed texture image.
 256  * \param col, row, img - image position (3D)
 257  * \param format - compressed image format
 258  * \param width - image width
 259  * \param image - the image address
 260  * \return address of pixel at (row, col)
 261  */
 262 GLubyte *
 263 _mesa_compressed_image_address(GLint col, GLint row, GLint img,
 264                                gl_format mesaFormat,
 265                                GLsizei width, const GLubyte *image)
 266 {
 267    GLubyte *addr;
 268
 269    (void) img;
 270
 271    /* We try to spot a "complete" subtexture "above" ROW, COL;
 272     * this texture is given by appropriate rounding of WIDTH x ROW.
 273     * Then we just add the amount left (usually on the left).
 274     *
 275     * Example for X*Y microtiles (Z bytes each)
 276     * offset = Z * (((width + X - 1) / X) * (row / Y) + col / X);
 277     */
 278
 279    switch (mesaFormat) {
 280 #if FEATURE_texture_fxt1
 281    case MESA_FORMAT_RGB_FXT1:
 282    case MESA_FORMAT_RGBA_FXT1:
 283       addr = (GLubyte *) image + 16 * (((width + 7) / 8) * (row / 4) + col / 8);
 284       break;
 285 #endif
 286 #if FEATURE_texture_s3tc
 287    case MESA_FORMAT_RGB_DXT1:
 288    case MESA_FORMAT_RGBA_DXT1:
 289 #if FEATURE_EXT_texture_sRGB
 290    case MESA_FORMAT_SRGB_DXT1:
 291    case MESA_FORMAT_SRGBA_DXT1:
 292 #endif
 293       addr = (GLubyte *) image + 8 * (((width + 3) / 4) * (row / 4) + col / 4);
 294       break;
 295    case MESA_FORMAT_RGBA_DXT3:
 296    case MESA_FORMAT_RGBA_DXT5:
 297 #if FEATURE_EXT_texture_sRGB
 298    case MESA_FORMAT_SRGBA_DXT3:
 299    case MESA_FORMAT_SRGBA_DXT5:
 300 #endif
 301       addr = (GLubyte *) image + 16 * (((width + 3) / 4) * (row / 4) + col / 4);
 302       break;
 303 #endif
 304    default:
 305       _mesa_problem(NULL, "bad mesaFormat in _mesa_compressed_image_address");
 306       addr = NULL;
 307    }
 308
 309    return addr;
 310 }