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 "formats.h"
  37 #include "mfeatures.h"
  38 #include "mtypes.h"
  39 #include "texcompress.h"
  40
  41
  42 /**
  43  * Return list of (and count of) all specific texture compression
  44  * formats that are supported.
  45  *
  46  * \param ctx  the GL context
  47  * \param formats  the resulting format list (may be NULL).
  48  * \param all  if true return all formats, even those with  some kind
  49  *             of restrictions/limitations (See GL_ARB_texture_compression
  50  *             spec for more info).
  51  *
  52  * \return number of formats.
  53  */
  54 GLuint
  55 _mesa_get_compressed_formats(struct gl_context *ctx, GLint *formats, GLboolean all)
  56 {
  57    GLuint n = 0;
  58    if (ctx->Extensions.TDFX_texture_compression_FXT1) {
  59       if (formats) {
  60          formats[n++] = GL_COMPRESSED_RGB_FXT1_3DFX;
  61          formats[n++] = GL_COMPRESSED_RGBA_FXT1_3DFX;
  62       }
  63       else {
  64          n += 2;
  65       }
  66    }
  67    if (ctx->Extensions.EXT_texture_compression_s3tc) {
  68       if (formats) {
  69          formats[n++] = GL_COMPRESSED_RGB_S3TC_DXT1_EXT;
  70          /* This format has some restrictions/limitations and so should
  71           * not be returned via the GL_COMPRESSED_TEXTURE_FORMATS query.
  72           * Specifically, all transparent pixels become black.  NVIDIA
  73           * omits this format too.
  74           */
  75          if (all)
  76              formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT1_EXT;
  77          formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT3_EXT;
  78          formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT5_EXT;
  79       }
  80       else {
  81          n += 3;
  82          if (all)
  83              n += 1;
  84       }
  85    }
  86    if (ctx->Extensions.S3_s3tc) {
  87       if (formats) {
  88          formats[n++] = GL_RGB_S3TC;
  89          formats[n++] = GL_RGB4_S3TC;
  90          formats[n++] = GL_RGBA_S3TC;
  91          formats[n++] = GL_RGBA4_S3TC;
  92       }
  93       else {
  94          n += 4;
  95       }
  96    }
  97 #if FEATURE_EXT_texture_sRGB
  98    if (ctx->Extensions.EXT_texture_sRGB) {
  99       if (formats) {
 100          formats[n++] = GL_COMPRESSED_SRGB_S3TC_DXT1_EXT;
 101          formats[n++] = GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT;
 102          formats[n++] = GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT;
 103          formats[n++] = GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT;
 104       }
 105       else {
 106          n += 4;
 107       }
 108    }
 109 #endif /* FEATURE_EXT_texture_sRGB */
 110    return n;
 111
 112 #if FEATURE_ES1 || FEATURE_ES2
 113    if (formats) {
 114       formats[n++] = GL_PALETTE4_RGB8_OES;
 115       formats[n++] = GL_PALETTE4_RGBA8_OES;
 116       formats[n++] = GL_PALETTE4_R5_G6_B5_OES;
 117       formats[n++] = GL_PALETTE4_RGBA4_OES;
 118       formats[n++] = GL_PALETTE4_RGB5_A1_OES;
 119       formats[n++] = GL_PALETTE8_RGB8_OES;
 120       formats[n++] = GL_PALETTE8_RGBA8_OES;
 121       formats[n++] = GL_PALETTE8_R5_G6_B5_OES;
 122       formats[n++] = GL_PALETTE8_RGBA4_OES;
 123       formats[n++] = GL_PALETTE8_RGB5_A1_OES;
 124    }
 125    else {
 126       n += 10;
 127    }
 128 #endif
 129 }
 130
 131
 132 /**
 133  * Convert a compressed MESA_FORMAT_x to a GLenum.
 134  */
 135 gl_format
 136 _mesa_glenum_to_compressed_format(GLenum format)
 137 {
 138    switch (format) {
 139    case GL_COMPRESSED_RGB_FXT1_3DFX:
 140       return MESA_FORMAT_RGB_FXT1;
 141    case GL_COMPRESSED_RGBA_FXT1_3DFX:
 142       return MESA_FORMAT_RGBA_FXT1;
 143
 144    case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
 145    case GL_RGB_S3TC:
 146       return MESA_FORMAT_RGB_DXT1;
 147    case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
 148    case GL_RGB4_S3TC:
 149       return MESA_FORMAT_RGBA_DXT1;
 150    case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
 151    case GL_RGBA_S3TC:
 152       return MESA_FORMAT_RGBA_DXT3;
 153    case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
 154    case GL_RGBA4_S3TC:
 155       return MESA_FORMAT_RGBA_DXT5;
 156
 157    case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:
 158       return MESA_FORMAT_SRGB_DXT1;
 159    case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:
 160       return MESA_FORMAT_SRGBA_DXT1;
 161    case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:
 162       return MESA_FORMAT_SRGBA_DXT3;
 163    case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:
 164       return MESA_FORMAT_SRGBA_DXT5;
 165
 166    default:
 167       return MESA_FORMAT_NONE;
 168    }
 169 }
 170
 171
 172 /**
 173  * Given a compressed MESA_FORMAT_x value, return the corresponding
 174  * GLenum for that format.
 175  * This is needed for glGetTexLevelParameter(GL_TEXTURE_INTERNAL_FORMAT)
 176  * which must return the specific texture format used when the user might
 177  * have originally specified a generic compressed format in their
 178  * glTexImage2D() call.
 179  * For non-compressed textures, we always return the user-specified
 180  * internal format unchanged.
 181  */
 182 GLenum
 183 _mesa_compressed_format_to_glenum(struct gl_context *ctx, GLuint mesaFormat)
 184 {
 185    switch (mesaFormat) {
 186 #if FEATURE_texture_fxt1
 187    case MESA_FORMAT_RGB_FXT1:
 188       return GL_COMPRESSED_RGB_FXT1_3DFX;
 189    case MESA_FORMAT_RGBA_FXT1:
 190       return GL_COMPRESSED_RGBA_FXT1_3DFX;
 191 #endif
 192 #if FEATURE_texture_s3tc
 193    case MESA_FORMAT_RGB_DXT1:
 194       return GL_COMPRESSED_RGB_S3TC_DXT1_EXT;
 195    case MESA_FORMAT_RGBA_DXT1:
 196       return GL_COMPRESSED_RGBA_S3TC_DXT1_EXT;
 197    case MESA_FORMAT_RGBA_DXT3:
 198       return GL_COMPRESSED_RGBA_S3TC_DXT3_EXT;
 199    case MESA_FORMAT_RGBA_DXT5:
 200       return GL_COMPRESSED_RGBA_S3TC_DXT5_EXT;
 201 #if FEATURE_EXT_texture_sRGB
 202    case MESA_FORMAT_SRGB_DXT1:
 203       return GL_COMPRESSED_SRGB_S3TC_DXT1_EXT;
 204    case MESA_FORMAT_SRGBA_DXT1:
 205       return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT;
 206    case MESA_FORMAT_SRGBA_DXT3:
 207       return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT;
 208    case MESA_FORMAT_SRGBA_DXT5:
 209       return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT;
 210 #endif
 211 #endif
 212    default:
 213       _mesa_problem(ctx, "Unexpected mesa texture format in"
 214                     " _mesa_compressed_format_to_glenum()");
 215       return 0;
 216    }
 217 }
 218
 219
 220 /*
 221  * Return the address of the pixel at (col, row, img) in a
 222  * compressed texture image.
 223  * \param col, row, img - image position (3D), should be a multiple of the
 224  *                        format's block size.
 225  * \param format - compressed image format
 226  * \param width - image width (stride) in pixels
 227  * \param image - the image address
 228  * \return address of pixel at (row, col, img)
 229  */
 230 GLubyte *
 231 _mesa_compressed_image_address(GLint col, GLint row, GLint img,
 232                                gl_format mesaFormat,
 233                                GLsizei width, const GLubyte *image)
 234 {
 235    /* XXX only 2D images implemented, not 3D */
 236    const GLuint blockSize = _mesa_get_format_bytes(mesaFormat);
 237    GLuint bw, bh;
 238    GLint offset;
 239
 240    _mesa_get_format_block_size(mesaFormat, &bw, &bh);
 241
 242    ASSERT(col % bw == 0);
 243    ASSERT(row % bh == 0);
 244
 245    offset = ((width + bw - 1) / bw) * (row / bh) + col / bw;
 246    offset *= blockSize;
 247
 248    return (GLubyte *) image + offset;
 249 }