Synchronised line endinge with release branch

1 files changed, 526 insertions, 526 deletions

diff --git a/mesalib/src/mesa/main/texcompress.c b/mesalib/src/mesa/main/texcompress.c
index b821dd0c0..4e5c14cbb 100644
--- a/mesalib/src/mesa/main/texcompress.c
+++ b/mesalib/src/mesa/main/texcompress.c
@@ -1,526 +1,526 @@
-/*

- * Mesa 3-D graphics library

- * Version:  6.5.1

- *

- * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.

- * Copyright (c) 2008 VMware, 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 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

- * BRIAN PAUL 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.

- */

-

-

-/**

- * \file texcompress.c

- * Helper functions for texture compression.

- */

-

-

-#include "glheader.h"

-#include "imports.h"

-#include "colormac.h"

-#include "formats.h"

-#include "mfeatures.h"

-#include "mtypes.h"

-#include "texcompress.h"

-#include "texcompress_fxt1.h"

-#include "texcompress_rgtc.h"

-#include "texcompress_s3tc.h"

-

-

-/**

- * Get the GL base format of a specified GL compressed texture format

- *

- * From page 232 of the OpenGL 3.3 (Compatiblity Profile) spec:

- *

- *     "Compressed Internal Format      Base Internal Format    Type

- *     ---------------------------     --------------------    ---------

- *     COMPRESSED_ALPHA                ALPHA                   Generic

- *     COMPRESSED_LUMINANCE            LUMINANCE               Generic

- *     COMPRESSED_LUMINANCE_ALPHA      LUMINANCE_ALPHA         Generic

- *     COMPRESSED_INTENSITY            INTENSITY               Generic

- *     COMPRESSED_RED                  RED                     Generic

- *     COMPRESSED_RG                   RG                      Generic

- *     COMPRESSED_RGB                  RGB                     Generic

- *     COMPRESSED_RGBA                 RGBA                    Generic

- *     COMPRESSED_SRGB                 RGB                     Generic

- *     COMPRESSED_SRGB_ALPHA           RGBA                    Generic

- *     COMPRESSED_SLUMINANCE           LUMINANCE               Generic

- *     COMPRESSED_SLUMINANCE_ALPHA     LUMINANCE_ALPHA         Generic

- *     COMPRESSED_RED_RGTC1            RED                     Specific

- *     COMPRESSED_SIGNED_RED_RGTC1     RED                     Specific

- *     COMPRESSED_RG_RGTC2             RG                      Specific

- *     COMPRESSED_SIGNED_RG_RGTC2      RG                      Specific"

- *

- * \return

- * The base format of \c format if \c format is a compressed format (either

- * generic or specific.  Otherwise 0 is returned.

- */

-GLenum

-_mesa_gl_compressed_format_base_format(GLenum format)

-{

-   switch (format) {

-   case GL_COMPRESSED_RED:

-   case GL_COMPRESSED_RED_RGTC1:

-   case GL_COMPRESSED_SIGNED_RED_RGTC1:

-      return GL_RED;

-

-   case GL_COMPRESSED_RG:

-   case GL_COMPRESSED_RG_RGTC2:

-   case GL_COMPRESSED_SIGNED_RG_RGTC2:

-      return GL_RG;

-

-   case GL_COMPRESSED_RGB:

-   case GL_COMPRESSED_SRGB:

-   case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:

-   case GL_COMPRESSED_RGB_FXT1_3DFX:

-   case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:

-      return GL_RGB;

-

-   case GL_COMPRESSED_RGBA:

-   case GL_COMPRESSED_SRGB_ALPHA:

-   case GL_COMPRESSED_RGBA_BPTC_UNORM_ARB:

-   case GL_COMPRESSED_SRGB_ALPHA_BPTC_UNORM_ARB:

-   case GL_COMPRESSED_RGB_BPTC_SIGNED_FLOAT_ARB:

-   case GL_COMPRESSED_RGB_BPTC_UNSIGNED_FLOAT_ARB:

-   case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:

-   case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:

-   case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:

-   case GL_COMPRESSED_RGBA_FXT1_3DFX:

-   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:

-   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:

-   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:

-      return GL_RGBA;

-

-   case GL_COMPRESSED_ALPHA:

-      return GL_ALPHA;

-

-   case GL_COMPRESSED_LUMINANCE:

-   case GL_COMPRESSED_SLUMINANCE:

-   case GL_COMPRESSED_LUMINANCE_LATC1_EXT:

-   case GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT:

-      return GL_LUMINANCE;

-

-   case GL_COMPRESSED_LUMINANCE_ALPHA:

-   case GL_COMPRESSED_SLUMINANCE_ALPHA:

-   case GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT:

-   case GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT:

-   case GL_COMPRESSED_LUMINANCE_ALPHA_3DC_ATI:

-      return GL_LUMINANCE_ALPHA;

-

-   case GL_COMPRESSED_INTENSITY:

-      return GL_INTENSITY;

-

-   default:

-      return 0;

-   }

-}

-

-/**

- * Return list of (and count of) all specific texture compression

- * formats that are supported.

- *

- * Some formats are \b not returned by this function.  The

- * \c GL_COMPRESSED_TEXTURE_FORMATS query only returns formats that are

- * "suitable for general-purpose usage."  All texture compression extensions

- * have taken this to mean either linear RGB or linear RGBA.

- *

- * The GL_ARB_texture_compress_rgtc spec says:

- *

- *    "19) Should the GL_NUM_COMPRESSED_TEXTURE_FORMATS and

- *        GL_COMPRESSED_TEXTURE_FORMATS queries return the RGTC formats?

- *

- *        RESOLVED:  No.

- *

- *        The OpenGL 2.1 specification says "The only values returned

- *        by this query [GL_COMPRESSED_TEXTURE_FORMATS"] are those

- *        corresponding to formats suitable for general-purpose usage.

- *        The renderer will not enumerate formats with restrictions that

- *        need to be specifically understood prior to use."

- *

- *        Compressed textures with just red or red-green components are

- *        not general-purpose so should not be returned by these queries

- *        because they have restrictions.

- *

- *        Applications that seek to use the RGTC formats should do so

- *        by looking for this extension's name in the string returned by

- *        glGetString(GL_EXTENSIONS) rather than

- *        what GL_NUM_COMPRESSED_TEXTURE_FORMATS and

- *        GL_COMPRESSED_TEXTURE_FORMATS return."

- *

- * There is nearly identical wording in the GL_EXT_texture_compression_rgtc

- * spec.

- *

- * The GL_EXT_texture_rRGB spec says:

- *

- *    "22) Should the new COMPRESSED_SRGB_* formats be listed in an

- *        implementation's GL_COMPRESSED_TEXTURE_FORMATS list?

- *

- *        RESOLVED:  No.  Section 3.8.1 says formats listed by

- *        GL_COMPRESSED_TEXTURE_FORMATS are "suitable for general-purpose

- *        usage."  The non-linear distribution of red, green, and

- *        blue for these sRGB compressed formats makes them not really

- *        general-purpose."

- *

- * The GL_EXT_texture_compression_latc spec says:

- *

- *    "16) Should the GL_NUM_COMPRESSED_TEXTURE_FORMATS and

- *        GL_COMPRESSED_TEXTURE_FORMATS queries return the LATC formats?

- *

- *        RESOLVED:  No.

- *

- *        The OpenGL 2.1 specification says "The only values returned

- *        by this query [GL_COMPRESSED_TEXTURE_FORMATS"] are those

- *        corresponding to formats suitable for general-purpose usage.

- *        The renderer will not enumerate formats with restrictions that

- *        need to be specifically understood prior to use."

- *

- *        Historically, OpenGL implementation have advertised the RGB and

- *        RGBA versions of the S3TC extensions compressed format tokens

- *        through this mechanism.

- *

- *        The specification is not sufficiently clear about what "suitable

- *        for general-purpose usage" means.  Historically that seems to mean

- *        unsigned RGB or unsigned RGBA.  The DXT1 format supporting alpha

- *        (GL_COMPRESSED_RGBA_S3TC_DXT1_EXT) is not exposed in the list (at

- *        least for NVIDIA drivers) because the alpha is always 1.0 expect

- *        when it is 0.0 when RGB is required to be black.  NVIDIA's even

- *        limits itself to true linear RGB or RGBA formats, specifically

- *        not including EXT_texture_sRGB's sRGB S3TC compressed formats.

- *

- *        Adding luminance and luminance-alpha texture formats (and

- *        certainly signed versions of luminance and luminance-alpha

- *        formats!) invites potential comptaibility problems with old

- *        applications using this mechanism since old applications are

- *        unlikely to expect non-RGB or non-RGBA formats to be advertised

- *        through this mechanism.  However no specific misinteractions

- *        with old applications is known.

- *

- *        Applications that seek to use the LATC formats should do so

- *        by looking for this extension's name in the string returned by

- *        glGetString(GL_EXTENSIONS) rather than

- *        what GL_NUM_COMPRESSED_TEXTURE_FORMATS and

- *        GL_COMPRESSED_TEXTURE_FORMATS return."

- *

- * There is no formal spec for GL_ATI_texture_compression_3dc.  Since the

- * formats added by this extension are luminance-alpha formats, it is

- * reasonable to expect them to follow the same rules as

- * GL_EXT_texture_compression_latc.  At the very least, Catalyst 11.6 does not

- * expose the 3dc formats through this mechanism.

- *

- * \param ctx  the GL context

- * \param formats  the resulting format list (may be NULL).

- *

- * \return number of formats.

- */

-GLuint

-_mesa_get_compressed_formats(struct gl_context *ctx, GLint *formats)

-{

-   GLuint n = 0;

-   if (ctx->Extensions.TDFX_texture_compression_FXT1) {

-      if (formats) {

-         formats[n++] = GL_COMPRESSED_RGB_FXT1_3DFX;

-         formats[n++] = GL_COMPRESSED_RGBA_FXT1_3DFX;

-      }

-      else {

-         n += 2;

-      }

-   }

-

-   if (ctx->Extensions.EXT_texture_compression_s3tc) {

-      if (formats) {

-         formats[n++] = GL_COMPRESSED_RGB_S3TC_DXT1_EXT;

-         formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT3_EXT;

-         formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT5_EXT;

-      }

-      else {

-         n += 3;

-      }

-   }

-   if (ctx->Extensions.S3_s3tc) {

-      if (formats) {

-         formats[n++] = GL_RGB_S3TC;

-         formats[n++] = GL_RGB4_S3TC;

-         formats[n++] = GL_RGBA_S3TC;

-         formats[n++] = GL_RGBA4_S3TC;

-      }

-      else {

-         n += 4;

-      }

-   }

-

-#if FEATURE_ES1 || FEATURE_ES2

-   if (formats) {

-      formats[n++] = GL_PALETTE4_RGB8_OES;

-      formats[n++] = GL_PALETTE4_RGBA8_OES;

-      formats[n++] = GL_PALETTE4_R5_G6_B5_OES;

-      formats[n++] = GL_PALETTE4_RGBA4_OES;

-      formats[n++] = GL_PALETTE4_RGB5_A1_OES;

-      formats[n++] = GL_PALETTE8_RGB8_OES;

-      formats[n++] = GL_PALETTE8_RGBA8_OES;

-      formats[n++] = GL_PALETTE8_R5_G6_B5_OES;

-      formats[n++] = GL_PALETTE8_RGBA4_OES;

-      formats[n++] = GL_PALETTE8_RGB5_A1_OES;

-   }

-   else {

-      n += 10;

-   }

-#endif

-

-   return n;

-}

-

-

-/**

- * Convert a compressed MESA_FORMAT_x to a GLenum.

- */

-gl_format

-_mesa_glenum_to_compressed_format(GLenum format)

-{

-   switch (format) {

-   case GL_COMPRESSED_RGB_FXT1_3DFX:

-      return MESA_FORMAT_RGB_FXT1;

-   case GL_COMPRESSED_RGBA_FXT1_3DFX:

-      return MESA_FORMAT_RGBA_FXT1;

-

-   case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:

-   case GL_RGB_S3TC:

-      return MESA_FORMAT_RGB_DXT1;

-   case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:

-   case GL_RGB4_S3TC:

-      return MESA_FORMAT_RGBA_DXT1;

-   case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:

-   case GL_RGBA_S3TC:

-      return MESA_FORMAT_RGBA_DXT3;

-   case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:

-   case GL_RGBA4_S3TC:

-      return MESA_FORMAT_RGBA_DXT5;

-

-   case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:

-      return MESA_FORMAT_SRGB_DXT1;

-   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:

-      return MESA_FORMAT_SRGBA_DXT1;

-   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:

-      return MESA_FORMAT_SRGBA_DXT3;

-   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:

-      return MESA_FORMAT_SRGBA_DXT5;

-

-   case GL_COMPRESSED_RED_RGTC1:

-      return MESA_FORMAT_RED_RGTC1;

-   case GL_COMPRESSED_SIGNED_RED_RGTC1:

-      return MESA_FORMAT_SIGNED_RED_RGTC1;

-   case GL_COMPRESSED_RG_RGTC2:

-      return MESA_FORMAT_RG_RGTC2;

-   case GL_COMPRESSED_SIGNED_RG_RGTC2:

-      return MESA_FORMAT_SIGNED_RG_RGTC2;

-

-   case GL_COMPRESSED_LUMINANCE_LATC1_EXT:

-      return MESA_FORMAT_L_LATC1;

-   case GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT:

-      return MESA_FORMAT_SIGNED_L_LATC1;

-   case GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT:

-   case GL_COMPRESSED_LUMINANCE_ALPHA_3DC_ATI:

-      return MESA_FORMAT_LA_LATC2;

-   case GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT:

-      return MESA_FORMAT_SIGNED_LA_LATC2;

-

-   default:

-      return MESA_FORMAT_NONE;

-   }

-}

-

-

-/**

- * Given a compressed MESA_FORMAT_x value, return the corresponding

- * GLenum for that format.

- * This is needed for glGetTexLevelParameter(GL_TEXTURE_INTERNAL_FORMAT)

- * which must return the specific texture format used when the user might

- * have originally specified a generic compressed format in their

- * glTexImage2D() call.

- * For non-compressed textures, we always return the user-specified

- * internal format unchanged.

- */

-GLenum

-_mesa_compressed_format_to_glenum(struct gl_context *ctx, GLuint mesaFormat)

-{

-   switch (mesaFormat) {

-#if FEATURE_texture_fxt1

-   case MESA_FORMAT_RGB_FXT1:

-      return GL_COMPRESSED_RGB_FXT1_3DFX;

-   case MESA_FORMAT_RGBA_FXT1:

-      return GL_COMPRESSED_RGBA_FXT1_3DFX;

-#endif

-#if FEATURE_texture_s3tc

-   case MESA_FORMAT_RGB_DXT1:

-      return GL_COMPRESSED_RGB_S3TC_DXT1_EXT;

-   case MESA_FORMAT_RGBA_DXT1:

-      return GL_COMPRESSED_RGBA_S3TC_DXT1_EXT;

-   case MESA_FORMAT_RGBA_DXT3:

-      return GL_COMPRESSED_RGBA_S3TC_DXT3_EXT;

-   case MESA_FORMAT_RGBA_DXT5:

-      return GL_COMPRESSED_RGBA_S3TC_DXT5_EXT;

-#if FEATURE_EXT_texture_sRGB

-   case MESA_FORMAT_SRGB_DXT1:

-      return GL_COMPRESSED_SRGB_S3TC_DXT1_EXT;

-   case MESA_FORMAT_SRGBA_DXT1:

-      return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT;

-   case MESA_FORMAT_SRGBA_DXT3:

-      return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT;

-   case MESA_FORMAT_SRGBA_DXT5:

-      return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT;

-#endif

-#endif

-

-   case MESA_FORMAT_RED_RGTC1:

-      return GL_COMPRESSED_RED_RGTC1;

-   case MESA_FORMAT_SIGNED_RED_RGTC1:

-      return GL_COMPRESSED_SIGNED_RED_RGTC1;

-   case MESA_FORMAT_RG_RGTC2:

-      return GL_COMPRESSED_RG_RGTC2;

-   case MESA_FORMAT_SIGNED_RG_RGTC2:

-      return GL_COMPRESSED_SIGNED_RG_RGTC2;

-

-   case MESA_FORMAT_L_LATC1:

-      return GL_COMPRESSED_LUMINANCE_LATC1_EXT;

-   case MESA_FORMAT_SIGNED_L_LATC1:

-      return GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT;

-   case MESA_FORMAT_LA_LATC2:

-      return GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT;

-   case MESA_FORMAT_SIGNED_LA_LATC2:

-      return GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT;

-

-   default:

-      _mesa_problem(ctx, "Unexpected mesa texture format in"

-                    " _mesa_compressed_format_to_glenum()");

-      return 0;

-   }

-}

-

-

-/*

- * Return the address of the pixel at (col, row, img) in a

- * compressed texture image.

- * \param col, row, img - image position (3D), should be a multiple of the

- *                        format's block size.

- * \param format - compressed image format

- * \param width - image width (stride) in pixels

- * \param image - the image address

- * \return address of pixel at (row, col, img)

- */

-GLubyte *

-_mesa_compressed_image_address(GLint col, GLint row, GLint img,

-                               gl_format mesaFormat,

-                               GLsizei width, const GLubyte *image)

-{

-   /* XXX only 2D images implemented, not 3D */

-   const GLuint blockSize = _mesa_get_format_bytes(mesaFormat);

-   GLuint bw, bh;

-   GLint offset;

-

-   _mesa_get_format_block_size(mesaFormat, &bw, &bh);

-

-   ASSERT(col % bw == 0);

-   ASSERT(row % bh == 0);

-

-   offset = ((width + bw - 1) / bw) * (row / bh) + col / bw;

-   offset *= blockSize;

-

-   return (GLubyte *) image + offset;

-}

-

-

-/**

- * Decompress a compressed texture image, returning a GL_RGBA/GL_FLOAT image.

- */

-void

-_mesa_decompress_image(gl_format format, GLuint width, GLuint height,

-                       const GLubyte *src, GLint srcRowStride,

-                       GLfloat *dest)

-{

-   void (*fetch)(const struct gl_texture_image *texImage,

-                 GLint i, GLint j, GLint k, GLfloat *texel);

-   struct gl_texture_image texImage;  /* dummy teximage */

-   GLuint i, j;

-

-   /* setup dummy texture image info */

-   memset(&texImage, 0, sizeof(texImage));

-   texImage.Data = (void *) src;

-   texImage.RowStride = srcRowStride;

-

-   switch (format) {

-   /* DXT formats */

-   case MESA_FORMAT_RGB_DXT1:

-      fetch = _mesa_fetch_texel_2d_f_rgb_dxt1;

-      break;

-   case MESA_FORMAT_RGBA_DXT1:

-      fetch = _mesa_fetch_texel_2d_f_rgba_dxt1;

-      break;

-   case MESA_FORMAT_RGBA_DXT3:

-      fetch = _mesa_fetch_texel_2d_f_rgba_dxt3;

-      break;

-   case MESA_FORMAT_RGBA_DXT5:

-      fetch = _mesa_fetch_texel_2d_f_rgba_dxt5;

-      break;

-

-   /* FXT1 formats */

-   case MESA_FORMAT_RGB_FXT1:

-      fetch = _mesa_fetch_texel_2d_f_rgb_fxt1;

-      break;

-   case MESA_FORMAT_RGBA_FXT1:

-      fetch = _mesa_fetch_texel_2d_f_rgba_fxt1;

-      break;

-

-   /* Red/RG formats */

-   case MESA_FORMAT_RED_RGTC1:

-      fetch = _mesa_fetch_texel_2d_f_red_rgtc1;

-      break;

-   case MESA_FORMAT_SIGNED_RED_RGTC1:

-      fetch = _mesa_fetch_texel_2d_f_signed_red_rgtc1;

-      break;

-   case MESA_FORMAT_RG_RGTC2:

-      fetch = _mesa_fetch_texel_2d_f_rg_rgtc2;

-      break;

-   case MESA_FORMAT_SIGNED_RG_RGTC2:

-      fetch = _mesa_fetch_texel_2d_f_signed_rg_rgtc2;

-      break;

-

-   /* L/LA formats */

-   case MESA_FORMAT_L_LATC1:

-      fetch = _mesa_fetch_texel_2d_f_l_latc1;

-      break;

-   case MESA_FORMAT_SIGNED_L_LATC1:

-      fetch = _mesa_fetch_texel_2d_f_signed_l_latc1;

-      break;

-   case MESA_FORMAT_LA_LATC2:

-      fetch = _mesa_fetch_texel_2d_f_la_latc2;

-      break;

-   case MESA_FORMAT_SIGNED_LA_LATC2:

-      fetch = _mesa_fetch_texel_2d_f_signed_la_latc2;

-      break;

-

-   default:

-      _mesa_problem(NULL, "Unexpected format in _mesa_decompress_image()");

-      return;

-   }

-

-   for (j = 0; j < height; j++) {

-      for (i = 0; i < width; i++) {

-         fetch(&texImage, i, j, 0, dest);

-         dest += 4;

-      }

-   }

-}

+/*
+ * Mesa 3-D graphics library
+ * Version:  6.5.1
+ *
+ * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
+ * Copyright (c) 2008 VMware, 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 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
+ * BRIAN PAUL 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.
+ */
+
+
+/**
+ * \file texcompress.c
+ * Helper functions for texture compression.
+ */
+
+
+#include "glheader.h"
+#include "imports.h"
+#include "colormac.h"
+#include "formats.h"
+#include "mfeatures.h"
+#include "mtypes.h"
+#include "texcompress.h"
+#include "texcompress_fxt1.h"
+#include "texcompress_rgtc.h"
+#include "texcompress_s3tc.h"
+
+
+/**
+ * Get the GL base format of a specified GL compressed texture format
+ *
+ * From page 232 of the OpenGL 3.3 (Compatiblity Profile) spec:
+ *
+ *     "Compressed Internal Format      Base Internal Format    Type
+ *     ---------------------------     --------------------    ---------
+ *     COMPRESSED_ALPHA                ALPHA                   Generic
+ *     COMPRESSED_LUMINANCE            LUMINANCE               Generic
+ *     COMPRESSED_LUMINANCE_ALPHA      LUMINANCE_ALPHA         Generic
+ *     COMPRESSED_INTENSITY            INTENSITY               Generic
+ *     COMPRESSED_RED                  RED                     Generic
+ *     COMPRESSED_RG                   RG                      Generic
+ *     COMPRESSED_RGB                  RGB                     Generic
+ *     COMPRESSED_RGBA                 RGBA                    Generic
+ *     COMPRESSED_SRGB                 RGB                     Generic
+ *     COMPRESSED_SRGB_ALPHA           RGBA                    Generic
+ *     COMPRESSED_SLUMINANCE           LUMINANCE               Generic
+ *     COMPRESSED_SLUMINANCE_ALPHA     LUMINANCE_ALPHA         Generic
+ *     COMPRESSED_RED_RGTC1            RED                     Specific
+ *     COMPRESSED_SIGNED_RED_RGTC1     RED                     Specific
+ *     COMPRESSED_RG_RGTC2             RG                      Specific
+ *     COMPRESSED_SIGNED_RG_RGTC2      RG                      Specific"
+ *
+ * \return
+ * The base format of \c format if \c format is a compressed format (either
+ * generic or specific.  Otherwise 0 is returned.
+ */
+GLenum
+_mesa_gl_compressed_format_base_format(GLenum format)
+{
+   switch (format) {
+   case GL_COMPRESSED_RED:
+   case GL_COMPRESSED_RED_RGTC1:
+   case GL_COMPRESSED_SIGNED_RED_RGTC1:
+      return GL_RED;
+
+   case GL_COMPRESSED_RG:
+   case GL_COMPRESSED_RG_RGTC2:
+   case GL_COMPRESSED_SIGNED_RG_RGTC2:
+      return GL_RG;
+
+   case GL_COMPRESSED_RGB:
+   case GL_COMPRESSED_SRGB:
+   case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
+   case GL_COMPRESSED_RGB_FXT1_3DFX:
+   case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:
+      return GL_RGB;
+
+   case GL_COMPRESSED_RGBA:
+   case GL_COMPRESSED_SRGB_ALPHA:
+   case GL_COMPRESSED_RGBA_BPTC_UNORM_ARB:
+   case GL_COMPRESSED_SRGB_ALPHA_BPTC_UNORM_ARB:
+   case GL_COMPRESSED_RGB_BPTC_SIGNED_FLOAT_ARB:
+   case GL_COMPRESSED_RGB_BPTC_UNSIGNED_FLOAT_ARB:
+   case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
+   case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
+   case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
+   case GL_COMPRESSED_RGBA_FXT1_3DFX:
+   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:
+   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:
+   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:
+      return GL_RGBA;
+
+   case GL_COMPRESSED_ALPHA:
+      return GL_ALPHA;
+
+   case GL_COMPRESSED_LUMINANCE:
+   case GL_COMPRESSED_SLUMINANCE:
+   case GL_COMPRESSED_LUMINANCE_LATC1_EXT:
+   case GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT:
+      return GL_LUMINANCE;
+
+   case GL_COMPRESSED_LUMINANCE_ALPHA:
+   case GL_COMPRESSED_SLUMINANCE_ALPHA:
+   case GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT:
+   case GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT:
+   case GL_COMPRESSED_LUMINANCE_ALPHA_3DC_ATI:
+      return GL_LUMINANCE_ALPHA;
+
+   case GL_COMPRESSED_INTENSITY:
+      return GL_INTENSITY;
+
+   default:
+      return 0;
+   }
+}
+
+/**
+ * Return list of (and count of) all specific texture compression
+ * formats that are supported.
+ *
+ * Some formats are \b not returned by this function.  The
+ * \c GL_COMPRESSED_TEXTURE_FORMATS query only returns formats that are
+ * "suitable for general-purpose usage."  All texture compression extensions
+ * have taken this to mean either linear RGB or linear RGBA.
+ *
+ * The GL_ARB_texture_compress_rgtc spec says:
+ *
+ *    "19) Should the GL_NUM_COMPRESSED_TEXTURE_FORMATS and
+ *        GL_COMPRESSED_TEXTURE_FORMATS queries return the RGTC formats?
+ *
+ *        RESOLVED:  No.
+ *
+ *        The OpenGL 2.1 specification says "The only values returned
+ *        by this query [GL_COMPRESSED_TEXTURE_FORMATS"] are those
+ *        corresponding to formats suitable for general-purpose usage.
+ *        The renderer will not enumerate formats with restrictions that
+ *        need to be specifically understood prior to use."
+ *
+ *        Compressed textures with just red or red-green components are
+ *        not general-purpose so should not be returned by these queries
+ *        because they have restrictions.
+ *
+ *        Applications that seek to use the RGTC formats should do so
+ *        by looking for this extension's name in the string returned by
+ *        glGetString(GL_EXTENSIONS) rather than
+ *        what GL_NUM_COMPRESSED_TEXTURE_FORMATS and
+ *        GL_COMPRESSED_TEXTURE_FORMATS return."
+ *
+ * There is nearly identical wording in the GL_EXT_texture_compression_rgtc
+ * spec.
+ *
+ * The GL_EXT_texture_rRGB spec says:
+ *
+ *    "22) Should the new COMPRESSED_SRGB_* formats be listed in an
+ *        implementation's GL_COMPRESSED_TEXTURE_FORMATS list?
+ *
+ *        RESOLVED:  No.  Section 3.8.1 says formats listed by
+ *        GL_COMPRESSED_TEXTURE_FORMATS are "suitable for general-purpose
+ *        usage."  The non-linear distribution of red, green, and
+ *        blue for these sRGB compressed formats makes them not really
+ *        general-purpose."
+ *
+ * The GL_EXT_texture_compression_latc spec says:
+ *
+ *    "16) Should the GL_NUM_COMPRESSED_TEXTURE_FORMATS and
+ *        GL_COMPRESSED_TEXTURE_FORMATS queries return the LATC formats?
+ *
+ *        RESOLVED:  No.
+ *
+ *        The OpenGL 2.1 specification says "The only values returned
+ *        by this query [GL_COMPRESSED_TEXTURE_FORMATS"] are those
+ *        corresponding to formats suitable for general-purpose usage.
+ *        The renderer will not enumerate formats with restrictions that
+ *        need to be specifically understood prior to use."
+ *
+ *        Historically, OpenGL implementation have advertised the RGB and
+ *        RGBA versions of the S3TC extensions compressed format tokens
+ *        through this mechanism.
+ *
+ *        The specification is not sufficiently clear about what "suitable
+ *        for general-purpose usage" means.  Historically that seems to mean
+ *        unsigned RGB or unsigned RGBA.  The DXT1 format supporting alpha
+ *        (GL_COMPRESSED_RGBA_S3TC_DXT1_EXT) is not exposed in the list (at
+ *        least for NVIDIA drivers) because the alpha is always 1.0 expect
+ *        when it is 0.0 when RGB is required to be black.  NVIDIA's even
+ *        limits itself to true linear RGB or RGBA formats, specifically
+ *        not including EXT_texture_sRGB's sRGB S3TC compressed formats.
+ *
+ *        Adding luminance and luminance-alpha texture formats (and
+ *        certainly signed versions of luminance and luminance-alpha
+ *        formats!) invites potential comptaibility problems with old
+ *        applications using this mechanism since old applications are
+ *        unlikely to expect non-RGB or non-RGBA formats to be advertised
+ *        through this mechanism.  However no specific misinteractions
+ *        with old applications is known.
+ *
+ *        Applications that seek to use the LATC formats should do so
+ *        by looking for this extension's name in the string returned by
+ *        glGetString(GL_EXTENSIONS) rather than
+ *        what GL_NUM_COMPRESSED_TEXTURE_FORMATS and
+ *        GL_COMPRESSED_TEXTURE_FORMATS return."
+ *
+ * There is no formal spec for GL_ATI_texture_compression_3dc.  Since the
+ * formats added by this extension are luminance-alpha formats, it is
+ * reasonable to expect them to follow the same rules as
+ * GL_EXT_texture_compression_latc.  At the very least, Catalyst 11.6 does not
+ * expose the 3dc formats through this mechanism.
+ *
+ * \param ctx  the GL context
+ * \param formats  the resulting format list (may be NULL).
+ *
+ * \return number of formats.
+ */
+GLuint
+_mesa_get_compressed_formats(struct gl_context *ctx, GLint *formats)
+{
+   GLuint n = 0;
+   if (ctx->Extensions.TDFX_texture_compression_FXT1) {
+      if (formats) {
+         formats[n++] = GL_COMPRESSED_RGB_FXT1_3DFX;
+         formats[n++] = GL_COMPRESSED_RGBA_FXT1_3DFX;
+      }
+      else {
+         n += 2;
+      }
+   }
+
+   if (ctx->Extensions.EXT_texture_compression_s3tc) {
+      if (formats) {
+         formats[n++] = GL_COMPRESSED_RGB_S3TC_DXT1_EXT;
+         formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT3_EXT;
+         formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT5_EXT;
+      }
+      else {
+         n += 3;
+      }
+   }
+   if (ctx->Extensions.S3_s3tc) {
+      if (formats) {
+         formats[n++] = GL_RGB_S3TC;
+         formats[n++] = GL_RGB4_S3TC;
+         formats[n++] = GL_RGBA_S3TC;
+         formats[n++] = GL_RGBA4_S3TC;
+      }
+      else {
+         n += 4;
+      }
+   }
+
+#if FEATURE_ES1 || FEATURE_ES2
+   if (formats) {
+      formats[n++] = GL_PALETTE4_RGB8_OES;
+      formats[n++] = GL_PALETTE4_RGBA8_OES;
+      formats[n++] = GL_PALETTE4_R5_G6_B5_OES;
+      formats[n++] = GL_PALETTE4_RGBA4_OES;
+      formats[n++] = GL_PALETTE4_RGB5_A1_OES;
+      formats[n++] = GL_PALETTE8_RGB8_OES;
+      formats[n++] = GL_PALETTE8_RGBA8_OES;
+      formats[n++] = GL_PALETTE8_R5_G6_B5_OES;
+      formats[n++] = GL_PALETTE8_RGBA4_OES;
+      formats[n++] = GL_PALETTE8_RGB5_A1_OES;
+   }
+   else {
+      n += 10;
+   }
+#endif
+
+   return n;
+}
+
+
+/**
+ * Convert a compressed MESA_FORMAT_x to a GLenum.
+ */
+gl_format
+_mesa_glenum_to_compressed_format(GLenum format)
+{
+   switch (format) {
+   case GL_COMPRESSED_RGB_FXT1_3DFX:
+      return MESA_FORMAT_RGB_FXT1;
+   case GL_COMPRESSED_RGBA_FXT1_3DFX:
+      return MESA_FORMAT_RGBA_FXT1;
+
+   case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
+   case GL_RGB_S3TC:
+      return MESA_FORMAT_RGB_DXT1;
+   case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
+   case GL_RGB4_S3TC:
+      return MESA_FORMAT_RGBA_DXT1;
+   case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
+   case GL_RGBA_S3TC:
+      return MESA_FORMAT_RGBA_DXT3;
+   case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
+   case GL_RGBA4_S3TC:
+      return MESA_FORMAT_RGBA_DXT5;
+
+   case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:
+      return MESA_FORMAT_SRGB_DXT1;
+   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:
+      return MESA_FORMAT_SRGBA_DXT1;
+   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:
+      return MESA_FORMAT_SRGBA_DXT3;
+   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:
+      return MESA_FORMAT_SRGBA_DXT5;
+
+   case GL_COMPRESSED_RED_RGTC1:
+      return MESA_FORMAT_RED_RGTC1;
+   case GL_COMPRESSED_SIGNED_RED_RGTC1:
+      return MESA_FORMAT_SIGNED_RED_RGTC1;
+   case GL_COMPRESSED_RG_RGTC2:
+      return MESA_FORMAT_RG_RGTC2;
+   case GL_COMPRESSED_SIGNED_RG_RGTC2:
+      return MESA_FORMAT_SIGNED_RG_RGTC2;
+
+   case GL_COMPRESSED_LUMINANCE_LATC1_EXT:
+      return MESA_FORMAT_L_LATC1;
+   case GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT:
+      return MESA_FORMAT_SIGNED_L_LATC1;
+   case GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT:
+   case GL_COMPRESSED_LUMINANCE_ALPHA_3DC_ATI:
+      return MESA_FORMAT_LA_LATC2;
+   case GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT:
+      return MESA_FORMAT_SIGNED_LA_LATC2;
+
+   default:
+      return MESA_FORMAT_NONE;
+   }
+}
+
+
+/**
+ * Given a compressed MESA_FORMAT_x value, return the corresponding
+ * GLenum for that format.
+ * This is needed for glGetTexLevelParameter(GL_TEXTURE_INTERNAL_FORMAT)
+ * which must return the specific texture format used when the user might
+ * have originally specified a generic compressed format in their
+ * glTexImage2D() call.
+ * For non-compressed textures, we always return the user-specified
+ * internal format unchanged.
+ */
+GLenum
+_mesa_compressed_format_to_glenum(struct gl_context *ctx, GLuint mesaFormat)
+{
+   switch (mesaFormat) {
+#if FEATURE_texture_fxt1
+   case MESA_FORMAT_RGB_FXT1:
+      return GL_COMPRESSED_RGB_FXT1_3DFX;
+   case MESA_FORMAT_RGBA_FXT1:
+      return GL_COMPRESSED_RGBA_FXT1_3DFX;
+#endif
+#if FEATURE_texture_s3tc
+   case MESA_FORMAT_RGB_DXT1:
+      return GL_COMPRESSED_RGB_S3TC_DXT1_EXT;
+   case MESA_FORMAT_RGBA_DXT1:
+      return GL_COMPRESSED_RGBA_S3TC_DXT1_EXT;
+   case MESA_FORMAT_RGBA_DXT3:
+      return GL_COMPRESSED_RGBA_S3TC_DXT3_EXT;
+   case MESA_FORMAT_RGBA_DXT5:
+      return GL_COMPRESSED_RGBA_S3TC_DXT5_EXT;
+#if FEATURE_EXT_texture_sRGB
+   case MESA_FORMAT_SRGB_DXT1:
+      return GL_COMPRESSED_SRGB_S3TC_DXT1_EXT;
+   case MESA_FORMAT_SRGBA_DXT1:
+      return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT;
+   case MESA_FORMAT_SRGBA_DXT3:
+      return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT;
+   case MESA_FORMAT_SRGBA_DXT5:
+      return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT;
+#endif
+#endif
+
+   case MESA_FORMAT_RED_RGTC1:
+      return GL_COMPRESSED_RED_RGTC1;
+   case MESA_FORMAT_SIGNED_RED_RGTC1:
+      return GL_COMPRESSED_SIGNED_RED_RGTC1;
+   case MESA_FORMAT_RG_RGTC2:
+      return GL_COMPRESSED_RG_RGTC2;
+   case MESA_FORMAT_SIGNED_RG_RGTC2:
+      return GL_COMPRESSED_SIGNED_RG_RGTC2;
+
+   case MESA_FORMAT_L_LATC1:
+      return GL_COMPRESSED_LUMINANCE_LATC1_EXT;
+   case MESA_FORMAT_SIGNED_L_LATC1:
+      return GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT;
+   case MESA_FORMAT_LA_LATC2:
+      return GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT;
+   case MESA_FORMAT_SIGNED_LA_LATC2:
+      return GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT;
+
+   default:
+      _mesa_problem(ctx, "Unexpected mesa texture format in"
+                    " _mesa_compressed_format_to_glenum()");
+      return 0;
+   }
+}
+
+
+/*
+ * Return the address of the pixel at (col, row, img) in a
+ * compressed texture image.
+ * \param col, row, img - image position (3D), should be a multiple of the
+ *                        format's block size.
+ * \param format - compressed image format
+ * \param width - image width (stride) in pixels
+ * \param image - the image address
+ * \return address of pixel at (row, col, img)
+ */
+GLubyte *
+_mesa_compressed_image_address(GLint col, GLint row, GLint img,
+                               gl_format mesaFormat,
+                               GLsizei width, const GLubyte *image)
+{
+   /* XXX only 2D images implemented, not 3D */
+   const GLuint blockSize = _mesa_get_format_bytes(mesaFormat);
+   GLuint bw, bh;
+   GLint offset;
+
+   _mesa_get_format_block_size(mesaFormat, &bw, &bh);
+
+   ASSERT(col % bw == 0);
+   ASSERT(row % bh == 0);
+
+   offset = ((width + bw - 1) / bw) * (row / bh) + col / bw;
+   offset *= blockSize;
+
+   return (GLubyte *) image + offset;
+}
+
+
+/**
+ * Decompress a compressed texture image, returning a GL_RGBA/GL_FLOAT image.
+ */
+void
+_mesa_decompress_image(gl_format format, GLuint width, GLuint height,
+                       const GLubyte *src, GLint srcRowStride,
+                       GLfloat *dest)
+{
+   void (*fetch)(const struct gl_texture_image *texImage,
+                 GLint i, GLint j, GLint k, GLfloat *texel);
+   struct gl_texture_image texImage;  /* dummy teximage */
+   GLuint i, j;
+
+   /* setup dummy texture image info */
+   memset(&texImage, 0, sizeof(texImage));
+   texImage.Data = (void *) src;
+   texImage.RowStride = srcRowStride;
+
+   switch (format) {
+   /* DXT formats */
+   case MESA_FORMAT_RGB_DXT1:
+      fetch = _mesa_fetch_texel_2d_f_rgb_dxt1;
+      break;
+   case MESA_FORMAT_RGBA_DXT1:
+      fetch = _mesa_fetch_texel_2d_f_rgba_dxt1;
+      break;
+   case MESA_FORMAT_RGBA_DXT3:
+      fetch = _mesa_fetch_texel_2d_f_rgba_dxt3;
+      break;
+   case MESA_FORMAT_RGBA_DXT5:
+      fetch = _mesa_fetch_texel_2d_f_rgba_dxt5;
+      break;
+
+   /* FXT1 formats */
+   case MESA_FORMAT_RGB_FXT1:
+      fetch = _mesa_fetch_texel_2d_f_rgb_fxt1;
+      break;
+   case MESA_FORMAT_RGBA_FXT1:
+      fetch = _mesa_fetch_texel_2d_f_rgba_fxt1;
+      break;
+
+   /* Red/RG formats */
+   case MESA_FORMAT_RED_RGTC1:
+      fetch = _mesa_fetch_texel_2d_f_red_rgtc1;
+      break;
+   case MESA_FORMAT_SIGNED_RED_RGTC1:
+      fetch = _mesa_fetch_texel_2d_f_signed_red_rgtc1;
+      break;
+   case MESA_FORMAT_RG_RGTC2:
+      fetch = _mesa_fetch_texel_2d_f_rg_rgtc2;
+      break;
+   case MESA_FORMAT_SIGNED_RG_RGTC2:
+      fetch = _mesa_fetch_texel_2d_f_signed_rg_rgtc2;
+      break;
+
+   /* L/LA formats */
+   case MESA_FORMAT_L_LATC1:
+      fetch = _mesa_fetch_texel_2d_f_l_latc1;
+      break;
+   case MESA_FORMAT_SIGNED_L_LATC1:
+      fetch = _mesa_fetch_texel_2d_f_signed_l_latc1;
+      break;
+   case MESA_FORMAT_LA_LATC2:
+      fetch = _mesa_fetch_texel_2d_f_la_latc2;
+      break;
+   case MESA_FORMAT_SIGNED_LA_LATC2:
+      fetch = _mesa_fetch_texel_2d_f_signed_la_latc2;
+      break;
+
+   default:
+      _mesa_problem(NULL, "Unexpected format in _mesa_decompress_image()");
+      return;
+   }
+
+   for (j = 0; j < height; j++) {
+      for (i = 0; i < width; i++) {
+         fetch(&texImage, i, j, 0, dest);
+         dest += 4;
+      }
+   }
+}