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authormarha <marha@users.sourceforge.net>2011-09-12 11:27:51 +0200
committermarha <marha@users.sourceforge.net>2011-09-12 11:27:51 +0200
commitdafebc5bb70303f0b5baf0b087cf4d9a64b5c7f0 (patch)
treebdf833cc6a4fc9035411779e10dd9e8478201885 /mesalib/src/mesa/main/texcompress.c
parent0b40f5f4b54453a77f4b09c431f8efc6875da61f (diff)
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Synchronised line endinge with release branch
Diffstat (limited to 'mesalib/src/mesa/main/texcompress.c')
-rw-r--r--mesalib/src/mesa/main/texcompress.c1052
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;
+ }
+ }
+}