WebSVN – Kolibri OS – Blame – /contrib/sdk/sources/Mesa/src/mesa/main/texcompress.c

Rev	Author	Line No.	Line
4358	Serge	1	/*
		2	* Mesa 3-D graphics library
		3	*
		4	* Copyright (C) 1999-2006 Brian Paul All Rights Reserved.
		5	* Copyright (c) 2008 VMware, Inc.
		6	*
		7	* Permission is hereby granted, free of charge, to any person obtaining a
		8	* copy of this software and associated documentation files (the "Software"),
		9	* to deal in the Software without restriction, including without limitation
		10	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
		11	* and/or sell copies of the Software, and to permit persons to whom the
		12	* Software is furnished to do so, subject to the following conditions:
		13	*
		14	* The above copyright notice and this permission notice shall be included
		15	* in all copies or substantial portions of the Software.
		16	*
		17	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
		18	* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
		19	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
		20	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
		21	* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
		22	* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
		23	* OTHER DEALINGS IN THE SOFTWARE.
		24	*/
		25
		26
		27	/**
		28	* \file texcompress.c
		29	* Helper functions for texture compression.
		30	*/
		31
		32
		33	#include "glheader.h"
		34	#include "imports.h"
		35	#include "colormac.h"
		36	#include "context.h"
		37	#include "formats.h"
		38	#include "mtypes.h"
		39	#include "context.h"
		40	#include "texcompress.h"
		41	#include "texcompress_fxt1.h"
		42	#include "texcompress_rgtc.h"
		43	#include "texcompress_s3tc.h"
		44	#include "texcompress_etc.h"
		45
		46
		47	/**
		48	* Get the GL base format of a specified GL compressed texture format
		49	*
		50	* From page 232 of the OpenGL 3.3 (Compatiblity Profile) spec:
		51	*
		52	* "Compressed Internal Format Base Internal Format Type
		53	* --------------------------- -------------------- ---------
		54	* COMPRESSED_ALPHA ALPHA Generic
		55	* COMPRESSED_LUMINANCE LUMINANCE Generic
		56	* COMPRESSED_LUMINANCE_ALPHA LUMINANCE_ALPHA Generic
		57	* COMPRESSED_INTENSITY INTENSITY Generic
		58	* COMPRESSED_RED RED Generic
		59	* COMPRESSED_RG RG Generic
		60	* COMPRESSED_RGB RGB Generic
		61	* COMPRESSED_RGBA RGBA Generic
		62	* COMPRESSED_SRGB RGB Generic
		63	* COMPRESSED_SRGB_ALPHA RGBA Generic
		64	* COMPRESSED_SLUMINANCE LUMINANCE Generic
		65	* COMPRESSED_SLUMINANCE_ALPHA LUMINANCE_ALPHA Generic
		66	* COMPRESSED_RED_RGTC1 RED Specific
		67	* COMPRESSED_SIGNED_RED_RGTC1 RED Specific
		68	* COMPRESSED_RG_RGTC2 RG Specific
		69	* COMPRESSED_SIGNED_RG_RGTC2 RG Specific"
		70	*
		71	* \return
		72	* The base format of \c format if \c format is a compressed format (either
		73	* generic or specific. Otherwise 0 is returned.
		74	*/
		75	GLenum
		76	_mesa_gl_compressed_format_base_format(GLenum format)
		77	{
		78	switch (format) {
		79	case GL_COMPRESSED_RED:
		80	case GL_COMPRESSED_R11_EAC:
		81	case GL_COMPRESSED_RED_RGTC1:
		82	case GL_COMPRESSED_SIGNED_R11_EAC:
		83	case GL_COMPRESSED_SIGNED_RED_RGTC1:
		84	return GL_RED;
		85
		86	case GL_COMPRESSED_RG:
		87	case GL_COMPRESSED_RG11_EAC:
		88	case GL_COMPRESSED_RG_RGTC2:
		89	case GL_COMPRESSED_SIGNED_RG11_EAC:
		90	case GL_COMPRESSED_SIGNED_RG_RGTC2:
		91	return GL_RG;
		92
		93	case GL_COMPRESSED_RGB:
		94	case GL_COMPRESSED_SRGB:
		95	case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
		96	case GL_COMPRESSED_RGB_FXT1_3DFX:
		97	case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:
		98	case GL_ETC1_RGB8_OES:
		99	case GL_COMPRESSED_RGB8_ETC2:
		100	case GL_COMPRESSED_SRGB8_ETC2:
		101	return GL_RGB;
		102
		103	case GL_COMPRESSED_RGBA:
		104	case GL_COMPRESSED_SRGB_ALPHA:
		105	case GL_COMPRESSED_RGBA_BPTC_UNORM_ARB:
		106	case GL_COMPRESSED_SRGB_ALPHA_BPTC_UNORM_ARB:
		107	case GL_COMPRESSED_RGB_BPTC_SIGNED_FLOAT_ARB:
		108	case GL_COMPRESSED_RGB_BPTC_UNSIGNED_FLOAT_ARB:
		109	case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
		110	case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
		111	case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
		112	case GL_COMPRESSED_RGBA_FXT1_3DFX:
		113	case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:
		114	case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:
		115	case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:
		116	case GL_COMPRESSED_RGBA8_ETC2_EAC:
		117	case GL_COMPRESSED_SRGB8_ALPHA8_ETC2_EAC:
		118	case GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2:
		119	case GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2:
		120	return GL_RGBA;
		121
		122	case GL_COMPRESSED_ALPHA:
		123	return GL_ALPHA;
		124
		125	case GL_COMPRESSED_LUMINANCE:
		126	case GL_COMPRESSED_SLUMINANCE:
		127	case GL_COMPRESSED_LUMINANCE_LATC1_EXT:
		128	case GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT:
		129	return GL_LUMINANCE;
		130
		131	case GL_COMPRESSED_LUMINANCE_ALPHA:
		132	case GL_COMPRESSED_SLUMINANCE_ALPHA:
		133	case GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT:
		134	case GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT:
		135	case GL_COMPRESSED_LUMINANCE_ALPHA_3DC_ATI:
		136	return GL_LUMINANCE_ALPHA;
		137
		138	case GL_COMPRESSED_INTENSITY:
		139	return GL_INTENSITY;
		140
		141	default:
		142	return 0;
		143	}
		144	}
		145
		146	/**
		147	* Return list of (and count of) all specific texture compression
		148	* formats that are supported.
		149	*
		150	* Some formats are \b not returned by this function. The
		151	* \c GL_COMPRESSED_TEXTURE_FORMATS query only returns formats that are
		152	* "suitable for general-purpose usage." All texture compression extensions
		153	* have taken this to mean either linear RGB or linear RGBA.
		154	*
		155	* The GL_ARB_texture_compress_rgtc spec says:
		156	*
		157	* "19) Should the GL_NUM_COMPRESSED_TEXTURE_FORMATS and
		158	* GL_COMPRESSED_TEXTURE_FORMATS queries return the RGTC formats?
		159	*
		160	* RESOLVED: No.
		161	*
		162	* The OpenGL 2.1 specification says "The only values returned
		163	* by this query [GL_COMPRESSED_TEXTURE_FORMATS"] are those
		164	* corresponding to formats suitable for general-purpose usage.
		165	* The renderer will not enumerate formats with restrictions that
		166	* need to be specifically understood prior to use."
		167	*
		168	* Compressed textures with just red or red-green components are
		169	* not general-purpose so should not be returned by these queries
		170	* because they have restrictions.
		171	*
		172	* Applications that seek to use the RGTC formats should do so
		173	* by looking for this extension's name in the string returned by
		174	* glGetString(GL_EXTENSIONS) rather than
		175	* what GL_NUM_COMPRESSED_TEXTURE_FORMATS and
		176	* GL_COMPRESSED_TEXTURE_FORMATS return."
		177	*
		178	* There is nearly identical wording in the GL_EXT_texture_compression_rgtc
		179	* spec.
		180	*
		181	* The GL_EXT_texture_rRGB spec says:
		182	*
		183	* "22) Should the new COMPRESSED_SRGB_* formats be listed in an
		184	* implementation's GL_COMPRESSED_TEXTURE_FORMATS list?
		185	*
		186	* RESOLVED: No. Section 3.8.1 says formats listed by
		187	* GL_COMPRESSED_TEXTURE_FORMATS are "suitable for general-purpose
		188	* usage." The non-linear distribution of red, green, and
		189	* blue for these sRGB compressed formats makes them not really
		190	* general-purpose."
		191	*
		192	* The GL_EXT_texture_compression_latc spec says:
		193	*
		194	* "16) Should the GL_NUM_COMPRESSED_TEXTURE_FORMATS and
		195	* GL_COMPRESSED_TEXTURE_FORMATS queries return the LATC formats?
		196	*
		197	* RESOLVED: No.
		198	*
		199	* The OpenGL 2.1 specification says "The only values returned
		200	* by this query [GL_COMPRESSED_TEXTURE_FORMATS"] are those
		201	* corresponding to formats suitable for general-purpose usage.
		202	* The renderer will not enumerate formats with restrictions that
		203	* need to be specifically understood prior to use."
		204	*
		205	* Historically, OpenGL implementation have advertised the RGB and
		206	* RGBA versions of the S3TC extensions compressed format tokens
		207	* through this mechanism.
		208	*
		209	* The specification is not sufficiently clear about what "suitable
		210	* for general-purpose usage" means. Historically that seems to mean
		211	* unsigned RGB or unsigned RGBA. The DXT1 format supporting alpha
		212	* (GL_COMPRESSED_RGBA_S3TC_DXT1_EXT) is not exposed in the list (at
		213	* least for NVIDIA drivers) because the alpha is always 1.0 expect
		214	* when it is 0.0 when RGB is required to be black. NVIDIA's even
		215	* limits itself to true linear RGB or RGBA formats, specifically
		216	* not including EXT_texture_sRGB's sRGB S3TC compressed formats.
		217	*
		218	* Adding luminance and luminance-alpha texture formats (and
		219	* certainly signed versions of luminance and luminance-alpha
		220	* formats!) invites potential comptaibility problems with old
		221	* applications using this mechanism since old applications are
		222	* unlikely to expect non-RGB or non-RGBA formats to be advertised
		223	* through this mechanism. However no specific misinteractions
		224	* with old applications is known.
		225	*
		226	* Applications that seek to use the LATC formats should do so
		227	* by looking for this extension's name in the string returned by
		228	* glGetString(GL_EXTENSIONS) rather than
		229	* what GL_NUM_COMPRESSED_TEXTURE_FORMATS and
		230	* GL_COMPRESSED_TEXTURE_FORMATS return."
		231	*
		232	* There is no formal spec for GL_ATI_texture_compression_3dc. Since the
		233	* formats added by this extension are luminance-alpha formats, it is
		234	* reasonable to expect them to follow the same rules as
		235	* GL_EXT_texture_compression_latc. At the very least, Catalyst 11.6 does not
		236	* expose the 3dc formats through this mechanism.
		237	*
		238	* \param ctx the GL context
		239	* \param formats the resulting format list (may be NULL).
		240	*
		241	* \return number of formats.
		242	*/
		243	GLuint
		244	_mesa_get_compressed_formats(struct gl_context ctx, GLint formats)
		245	{
		246	GLuint n = 0;
		247	if (ctx->Extensions.TDFX_texture_compression_FXT1) {
		248	if (formats) {
		249	formats[n++] = GL_COMPRESSED_RGB_FXT1_3DFX;
		250	formats[n++] = GL_COMPRESSED_RGBA_FXT1_3DFX;
		251	}
		252	else {
		253	n += 2;
		254	}
		255	}
		256
		257	if (ctx->Extensions.EXT_texture_compression_s3tc) {
		258	if (formats) {
		259	formats[n++] = GL_COMPRESSED_RGB_S3TC_DXT1_EXT;
		260	formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT3_EXT;
		261	formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT5_EXT;
		262	}
		263	else {
		264	n += 3;
		265	}
		266	}
		267
		268	/* The GL_OES_compressed_ETC1_RGB8_texture spec says:
		269	*
		270	* "New State
		271	*
		272	* The queries for NUM_COMPRESSED_TEXTURE_FORMATS and
		273	* COMPRESSED_TEXTURE_FORMATS include ETC1_RGB8_OES."
		274	*/
		275	if (_mesa_is_gles(ctx)
		276	&& ctx->Extensions.OES_compressed_ETC1_RGB8_texture) {
		277	if (formats) {
		278	formats[n++] = GL_ETC1_RGB8_OES;
		279	}
		280	else {
		281	n += 1;
		282	}
		283	}
		284
		285	if (ctx->API == API_OPENGLES) {
		286	if (formats) {
		287	formats[n++] = GL_PALETTE4_RGB8_OES;
		288	formats[n++] = GL_PALETTE4_RGBA8_OES;
		289	formats[n++] = GL_PALETTE4_R5_G6_B5_OES;
		290	formats[n++] = GL_PALETTE4_RGBA4_OES;
		291	formats[n++] = GL_PALETTE4_RGB5_A1_OES;
		292	formats[n++] = GL_PALETTE8_RGB8_OES;
		293	formats[n++] = GL_PALETTE8_RGBA8_OES;
		294	formats[n++] = GL_PALETTE8_R5_G6_B5_OES;
		295	formats[n++] = GL_PALETTE8_RGBA4_OES;
		296	formats[n++] = GL_PALETTE8_RGB5_A1_OES;
		297	}
		298	else {
		299	n += 10;
		300	}
		301	}
		302
		303	if (_mesa_is_gles3(ctx)) {
		304	if (formats) {
		305	formats[n++] = GL_COMPRESSED_RGB8_ETC2;
		306	formats[n++] = GL_COMPRESSED_SRGB8_ETC2;
		307	formats[n++] = GL_COMPRESSED_RGBA8_ETC2_EAC;
		308	formats[n++] = GL_COMPRESSED_SRGB8_ALPHA8_ETC2_EAC;
		309	formats[n++] = GL_COMPRESSED_R11_EAC;
		310	formats[n++] = GL_COMPRESSED_RG11_EAC;
		311	formats[n++] = GL_COMPRESSED_SIGNED_R11_EAC;
		312	formats[n++] = GL_COMPRESSED_SIGNED_RG11_EAC;
		313	formats[n++] = GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2;
		314	formats[n++] = GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2;
		315	}
		316	else {
		317	n += 10;
		318	}
		319	}
		320	return n;
		321	}
		322
		323
		324	/**
		325	* Convert a compressed MESA_FORMAT_x to a GLenum.
		326	*/
		327	gl_format
		328	_mesa_glenum_to_compressed_format(GLenum format)
		329	{
		330	switch (format) {
		331	case GL_COMPRESSED_RGB_FXT1_3DFX:
		332	return MESA_FORMAT_RGB_FXT1;
		333	case GL_COMPRESSED_RGBA_FXT1_3DFX:
		334	return MESA_FORMAT_RGBA_FXT1;
		335
		336	case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
		337	case GL_RGB_S3TC:
		338	return MESA_FORMAT_RGB_DXT1;
		339	case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
		340	case GL_RGB4_S3TC:
		341	return MESA_FORMAT_RGBA_DXT1;
		342	case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
		343	case GL_RGBA_S3TC:
		344	return MESA_FORMAT_RGBA_DXT3;
		345	case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
		346	case GL_RGBA4_S3TC:
		347	return MESA_FORMAT_RGBA_DXT5;
		348
		349	case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:
		350	return MESA_FORMAT_SRGB_DXT1;
		351	case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:
		352	return MESA_FORMAT_SRGBA_DXT1;
		353	case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:
		354	return MESA_FORMAT_SRGBA_DXT3;
		355	case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:
		356	return MESA_FORMAT_SRGBA_DXT5;
		357
		358	case GL_COMPRESSED_RED_RGTC1:
		359	return MESA_FORMAT_RED_RGTC1;
		360	case GL_COMPRESSED_SIGNED_RED_RGTC1:
		361	return MESA_FORMAT_SIGNED_RED_RGTC1;
		362	case GL_COMPRESSED_RG_RGTC2:
		363	return MESA_FORMAT_RG_RGTC2;
		364	case GL_COMPRESSED_SIGNED_RG_RGTC2:
		365	return MESA_FORMAT_SIGNED_RG_RGTC2;
		366
		367	case GL_COMPRESSED_LUMINANCE_LATC1_EXT:
		368	return MESA_FORMAT_L_LATC1;
		369	case GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT:
		370	return MESA_FORMAT_SIGNED_L_LATC1;
		371	case GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT:
		372	case GL_COMPRESSED_LUMINANCE_ALPHA_3DC_ATI:
		373	return MESA_FORMAT_LA_LATC2;
		374	case GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT:
		375	return MESA_FORMAT_SIGNED_LA_LATC2;
		376
		377	case GL_ETC1_RGB8_OES:
		378	return MESA_FORMAT_ETC1_RGB8;
		379	case GL_COMPRESSED_RGB8_ETC2:
		380	return MESA_FORMAT_ETC2_RGB8;
		381	case GL_COMPRESSED_SRGB8_ETC2:
		382	return MESA_FORMAT_ETC2_SRGB8;
		383	case GL_COMPRESSED_RGBA8_ETC2_EAC:
		384	return MESA_FORMAT_ETC2_RGBA8_EAC;
		385	case GL_COMPRESSED_SRGB8_ALPHA8_ETC2_EAC:
		386	return MESA_FORMAT_ETC2_SRGB8_ALPHA8_EAC;
		387	case GL_COMPRESSED_R11_EAC:
		388	return MESA_FORMAT_ETC2_R11_EAC;
		389	case GL_COMPRESSED_RG11_EAC:
		390	return MESA_FORMAT_ETC2_RG11_EAC;
		391	case GL_COMPRESSED_SIGNED_R11_EAC:
		392	return MESA_FORMAT_ETC2_SIGNED_R11_EAC;
		393	case GL_COMPRESSED_SIGNED_RG11_EAC:
		394	return MESA_FORMAT_ETC2_SIGNED_RG11_EAC;
		395	case GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2:
		396	return MESA_FORMAT_ETC2_RGB8_PUNCHTHROUGH_ALPHA1;
		397	case GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2:
		398	return MESA_FORMAT_ETC2_SRGB8_PUNCHTHROUGH_ALPHA1;
		399
		400	default:
		401	return MESA_FORMAT_NONE;
		402	}
		403	}
		404
		405
		406	/**
		407	* Given a compressed MESA_FORMAT_x value, return the corresponding
		408	* GLenum for that format.
		409	* This is needed for glGetTexLevelParameter(GL_TEXTURE_INTERNAL_FORMAT)
		410	* which must return the specific texture format used when the user might
		411	* have originally specified a generic compressed format in their
		412	* glTexImage2D() call.
		413	* For non-compressed textures, we always return the user-specified
		414	* internal format unchanged.
		415	*/
		416	GLenum
		417	_mesa_compressed_format_to_glenum(struct gl_context *ctx, gl_format mesaFormat)
		418	{
		419	switch (mesaFormat) {
		420	case MESA_FORMAT_RGB_FXT1:
		421	return GL_COMPRESSED_RGB_FXT1_3DFX;
		422	case MESA_FORMAT_RGBA_FXT1:
		423	return GL_COMPRESSED_RGBA_FXT1_3DFX;
		424	case MESA_FORMAT_RGB_DXT1:
		425	return GL_COMPRESSED_RGB_S3TC_DXT1_EXT;
		426	case MESA_FORMAT_RGBA_DXT1:
		427	return GL_COMPRESSED_RGBA_S3TC_DXT1_EXT;
		428	case MESA_FORMAT_RGBA_DXT3:
		429	return GL_COMPRESSED_RGBA_S3TC_DXT3_EXT;
		430	case MESA_FORMAT_RGBA_DXT5:
		431	return GL_COMPRESSED_RGBA_S3TC_DXT5_EXT;
		432	case MESA_FORMAT_SRGB_DXT1:
		433	return GL_COMPRESSED_SRGB_S3TC_DXT1_EXT;
		434	case MESA_FORMAT_SRGBA_DXT1:
		435	return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT;
		436	case MESA_FORMAT_SRGBA_DXT3:
		437	return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT;
		438	case MESA_FORMAT_SRGBA_DXT5:
		439	return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT;
		440	case MESA_FORMAT_RED_RGTC1:
		441	return GL_COMPRESSED_RED_RGTC1;
		442	case MESA_FORMAT_SIGNED_RED_RGTC1:
		443	return GL_COMPRESSED_SIGNED_RED_RGTC1;
		444	case MESA_FORMAT_RG_RGTC2:
		445	return GL_COMPRESSED_RG_RGTC2;
		446	case MESA_FORMAT_SIGNED_RG_RGTC2:
		447	return GL_COMPRESSED_SIGNED_RG_RGTC2;
		448
		449	case MESA_FORMAT_L_LATC1:
		450	return GL_COMPRESSED_LUMINANCE_LATC1_EXT;
		451	case MESA_FORMAT_SIGNED_L_LATC1:
		452	return GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT;
		453	case MESA_FORMAT_LA_LATC2:
		454	return GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT;
		455	case MESA_FORMAT_SIGNED_LA_LATC2:
		456	return GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT;
		457
		458	case MESA_FORMAT_ETC1_RGB8:
		459	return GL_ETC1_RGB8_OES;
		460	case MESA_FORMAT_ETC2_RGB8:
		461	return GL_COMPRESSED_RGB8_ETC2;
		462	case MESA_FORMAT_ETC2_SRGB8:
		463	return GL_COMPRESSED_SRGB8_ETC2;
		464	case MESA_FORMAT_ETC2_RGBA8_EAC:
		465	return GL_COMPRESSED_RGBA8_ETC2_EAC;
		466	case MESA_FORMAT_ETC2_SRGB8_ALPHA8_EAC:
		467	return GL_COMPRESSED_SRGB8_ALPHA8_ETC2_EAC;
		468	case MESA_FORMAT_ETC2_R11_EAC:
		469	return GL_COMPRESSED_R11_EAC;
		470	case MESA_FORMAT_ETC2_RG11_EAC:
		471	return GL_COMPRESSED_RG11_EAC;
		472	case MESA_FORMAT_ETC2_SIGNED_R11_EAC:
		473	return GL_COMPRESSED_SIGNED_R11_EAC;
		474	case MESA_FORMAT_ETC2_SIGNED_RG11_EAC:
		475	return GL_COMPRESSED_SIGNED_RG11_EAC;
		476	case MESA_FORMAT_ETC2_RGB8_PUNCHTHROUGH_ALPHA1:
		477	return GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2;
		478	case MESA_FORMAT_ETC2_SRGB8_PUNCHTHROUGH_ALPHA1:
		479	return GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2;
		480
		481	default:
		482	_mesa_problem(ctx, "Unexpected mesa texture format in"
		483	" _mesa_compressed_format_to_glenum()");
		484	return 0;
		485	}
		486	}
		487
		488
		489	/*
		490	* Return the address of the pixel at (col, row, img) in a
		491	* compressed texture image.
		492	* \param col, row, img - image position (3D), should be a multiple of the
		493	* format's block size.
		494	* \param format - compressed image format
		495	* \param width - image width (stride) in pixels
		496	* \param image - the image address
		497	* \return address of pixel at (row, col, img)
		498	*/
		499	GLubyte *
		500	_mesa_compressed_image_address(GLint col, GLint row, GLint img,
		501	gl_format mesaFormat,
		502	GLsizei width, const GLubyte *image)
		503	{
		504	/* XXX only 2D images implemented, not 3D */
		505	const GLuint blockSize = _mesa_get_format_bytes(mesaFormat);
		506	GLuint bw, bh;
		507	GLint offset;
		508
		509	_mesa_get_format_block_size(mesaFormat, &bw, &bh);
		510
		511	ASSERT(col % bw == 0);
		512	ASSERT(row % bh == 0);
		513
		514	offset = ((width + bw - 1) / bw) * (row / bh) + col / bw;
		515	offset *= blockSize;
		516
		517	return (GLubyte *) image + offset;
		518	}
		519
		520
		521	/**
		522	* Return a texel-fetch function for the given format, or NULL if
		523	* invalid format.
		524	*/
		525	compressed_fetch_func
		526	_mesa_get_compressed_fetch_func(gl_format format)
		527	{
		528	switch (format) {
		529	case MESA_FORMAT_RGB_DXT1:
		530	case MESA_FORMAT_RGBA_DXT1:
		531	case MESA_FORMAT_RGBA_DXT3:
		532	case MESA_FORMAT_RGBA_DXT5:
		533	case MESA_FORMAT_SRGB_DXT1:
		534	case MESA_FORMAT_SRGBA_DXT1:
		535	case MESA_FORMAT_SRGBA_DXT3:
		536	case MESA_FORMAT_SRGBA_DXT5:
		537	return _mesa_get_dxt_fetch_func(format);
		538	case MESA_FORMAT_RGB_FXT1:
		539	case MESA_FORMAT_RGBA_FXT1:
		540	return _mesa_get_fxt_fetch_func(format);
		541	case MESA_FORMAT_RED_RGTC1:
		542	case MESA_FORMAT_L_LATC1:
		543	case MESA_FORMAT_SIGNED_RED_RGTC1:
		544	case MESA_FORMAT_SIGNED_L_LATC1:
		545	case MESA_FORMAT_RG_RGTC2:
		546	case MESA_FORMAT_LA_LATC2:
		547	case MESA_FORMAT_SIGNED_RG_RGTC2:
		548	case MESA_FORMAT_SIGNED_LA_LATC2:
		549	return _mesa_get_compressed_rgtc_func(format);
		550	case MESA_FORMAT_ETC1_RGB8:
		551	return _mesa_get_etc_fetch_func(format);
		552	default:
		553	return NULL;
		554	}
		555	}
		556
		557
		558	/**
		559	* Decompress a compressed texture image, returning a GL_RGBA/GL_FLOAT image.
		560	* \param srcRowStride stride in bytes between rows of blocks in the
		561	* compressed source image.
		562	*/
		563	void
		564	_mesa_decompress_image(gl_format format, GLuint width, GLuint height,
		565	const GLubyte *src, GLint srcRowStride,
		566	GLfloat *dest)
		567	{
		568	compressed_fetch_func fetch;
		569	GLuint i, j;
		570	GLuint bytes, bw, bh;
		571	GLint stride;
		572
		573	bytes = _mesa_get_format_bytes(format);
		574	_mesa_get_format_block_size(format, &bw, &bh);
		575
		576	fetch = _mesa_get_compressed_fetch_func(format);
		577	if (!fetch) {
		578	_mesa_problem(NULL, "Unexpected format in _mesa_decompress_image()");
		579	return;
		580	}
		581
		582	stride = srcRowStride * bh / bytes;
		583
		584	for (j = 0; j < height; j++) {
		585	for (i = 0; i < width; i++) {
		586	fetch(src, stride, i, j, dest);
		587	dest += 4;
		588	}
		589	}
		590	}

Subversion Repositories Kolibri OS

(root)/contrib/sdk/sources/Mesa/src/mesa/main/texcompress.c – Rev 4358