diff options
Diffstat (limited to 'mesalib/src/mesa/main/texcompress.c')
| -rw-r--r-- | mesalib/src/mesa/main/texcompress.c | 878 |
1 files changed, 439 insertions, 439 deletions
diff --git a/mesalib/src/mesa/main/texcompress.c b/mesalib/src/mesa/main/texcompress.c index 42bd1eee5..532f79fd5 100644 --- a/mesalib/src/mesa/main/texcompress.c +++ b/mesalib/src/mesa/main/texcompress.c @@ -1,439 +1,439 @@ -/* - * 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" - - -/** - * 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; - } - } - return n; - -#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 -} - - -/** - * 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; -} +/*
+ * 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"
+
+
+/**
+ * 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;
+ }
+ }
+ return n;
+
+#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
+}
+
+
+/**
+ * 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;
+}
|