* 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"),
#include "glheader.h"
#include "imports.h"
#include "colormac.h"
-#include "context.h"
-#include "image.h"
-#include "mipmap.h"
+#include "formats.h"
+#include "mfeatures.h"
+#include "mtypes.h"
#include "texcompress.h"
-#include "texformat.h"
-#include "texstore.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).
- * \param all if true return all formats, even those with some kind
- * of restrictions/limitations (See GL_ARB_texture_compression
- * spec for more info).
*
* \return number of formats.
*/
GLuint
-_mesa_get_compressed_formats(GLcontext *ctx, GLint *formats, GLboolean all)
+_mesa_get_compressed_formats(struct gl_context *ctx, GLint *formats)
{
GLuint n = 0;
- if (ctx->Extensions.ARB_texture_compression) {
- 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.TDFX_texture_compression_FXT1) {
+ if (formats) {
+ formats[n++] = GL_COMPRESSED_RGB_FXT1_3DFX;
+ formats[n++] = GL_COMPRESSED_RGBA_FXT1_3DFX;
}
- if (ctx->Extensions.EXT_texture_compression_s3tc) {
- if (formats) {
- formats[n++] = GL_COMPRESSED_RGB_S3TC_DXT1_EXT;
- /* This format has some restrictions/limitations and so should
- * not be returned via the GL_COMPRESSED_TEXTURE_FORMATS query.
- * Specifically, all transparent pixels become black. NVIDIA
- * omits this format too.
- */
- if (all)
- formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT1_EXT;
- formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT3_EXT;
- formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT5_EXT;
- }
- else {
- n += 3;
- if (all)
- n += 1;
- }
+ else {
+ n += 2;
}
- 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 (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;
}
-#if FEATURE_EXT_texture_sRGB
- if (ctx->Extensions.EXT_texture_sRGB) {
- if (formats) {
- formats[n++] = GL_COMPRESSED_SRGB_S3TC_DXT1_EXT;
- formats[n++] = GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT;
- formats[n++] = GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT;
- formats[n++] = GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT;
- }
- else {
- n += 4;
- }
+ 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;
}
-#endif /* FEATURE_EXT_texture_sRGB */
}
return n;
-}
-
-
-
-/**
- * Return number of bytes needed to store a texture of the given size
- * using the specified compressed format.
- * This is called via the ctx->Driver.CompressedTextureSize function,
- * unless a device driver overrides it.
- *
- * \param width texture width in texels.
- * \param height texture height in texels.
- * \param depth texture depth in texels.
- * \param mesaFormat one of the MESA_FORMAT_* compressed formats
- *
- * \return size in bytes, or zero if bad format
- */
-GLuint
-_mesa_compressed_texture_size( GLcontext *ctx,
- GLsizei width, GLsizei height, GLsizei depth,
- GLuint mesaFormat )
-{
- GLuint size;
- ASSERT(depth == 1);
- (void) depth;
- (void) size;
-
- switch (mesaFormat) {
-#if FEATURE_texture_fxt1
- case MESA_FORMAT_RGB_FXT1:
- case MESA_FORMAT_RGBA_FXT1:
- /* round up width to next multiple of 8, height to next multiple of 4 */
- width = (width + 7) & ~7;
- height = (height + 3) & ~3;
- /* 16 bytes per 8x4 tile of RGB[A] texels */
- size = width * height / 2;
- /* Textures smaller than 8x4 will effectively be made into 8x4 and
- * take 16 bytes.
- */
- return size;
-#endif
-#if FEATURE_texture_s3tc
- case MESA_FORMAT_RGB_DXT1:
- case MESA_FORMAT_RGBA_DXT1:
- /* round up width, height to next multiple of 4 */
- width = (width + 3) & ~3;
- height = (height + 3) & ~3;
- /* 8 bytes per 4x4 tile of RGB[A] texels */
- size = width * height / 2;
- /* Textures smaller than 4x4 will effectively be made into 4x4 and
- * take 8 bytes.
- */
- return size;
- case MESA_FORMAT_RGBA_DXT3:
- case MESA_FORMAT_RGBA_DXT5:
- /* round up width, height to next multiple of 4 */
- width = (width + 3) & ~3;
- height = (height + 3) & ~3;
- /* 16 bytes per 4x4 tile of RGBA texels */
- size = width * height; /* simple! */
- /* Textures smaller than 4x4 will effectively be made into 4x4 and
- * take 16 bytes.
- */
- return size;
-#endif
- default:
- _mesa_problem(ctx, "bad mesaFormat in _mesa_compressed_texture_size");
- return 0;
+#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
}
/**
- * As above, but format is specified by a GLenum (GL_COMPRESSED_*) token.
- *
- * Note: This function CAN NOT return a padded hardware texture size.
- * That's why we don't call the ctx->Driver.CompressedTextureSize() function.
- *
- * We use this function to validate the <imageSize> parameter
- * of glCompressedTex[Sub]Image1/2/3D(), which must be an exact match.
+ * Convert a compressed MESA_FORMAT_x to a GLenum.
*/
-GLuint
-_mesa_compressed_texture_size_glenum(GLcontext *ctx,
- GLsizei width, GLsizei height,
- GLsizei depth, GLenum glformat)
+gl_format
+_mesa_glenum_to_compressed_format(GLenum format)
{
- GLuint mesaFormat;
-
- switch (glformat) {
-#if FEATURE_texture_fxt1
+ switch (format) {
case GL_COMPRESSED_RGB_FXT1_3DFX:
- mesaFormat = MESA_FORMAT_RGB_FXT1;
- break;
+ return MESA_FORMAT_RGB_FXT1;
case GL_COMPRESSED_RGBA_FXT1_3DFX:
- mesaFormat = MESA_FORMAT_RGBA_FXT1;
- break;
-#endif
-#if FEATURE_texture_s3tc
+ return MESA_FORMAT_RGBA_FXT1;
+
case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
case GL_RGB_S3TC:
- mesaFormat = MESA_FORMAT_RGB_DXT1;
- break;
+ return MESA_FORMAT_RGB_DXT1;
case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
case GL_RGB4_S3TC:
- mesaFormat = MESA_FORMAT_RGBA_DXT1;
- break;
+ return MESA_FORMAT_RGBA_DXT1;
case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
case GL_RGBA_S3TC:
- mesaFormat = MESA_FORMAT_RGBA_DXT3;
- break;
+ return MESA_FORMAT_RGBA_DXT3;
case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
case GL_RGBA4_S3TC:
- mesaFormat = MESA_FORMAT_RGBA_DXT5;
- break;
-#endif
+ 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 0;
+ return MESA_FORMAT_NONE;
}
-
- return _mesa_compressed_texture_size(ctx, width, height, depth, mesaFormat);
}
-/*
- * Compute the bytes per row in a compressed texture image.
- * We use this for computing the destination address for sub-texture updates.
- * \param mesaFormat one of the MESA_FORMAT_* compressed formats
- * \param width image width in pixels
- * \return stride, in bytes, between rows for compressed image
+/**
+ * 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.
*/
-GLint
-_mesa_compressed_row_stride(GLuint mesaFormat, GLsizei width)
+GLenum
+_mesa_compressed_format_to_glenum(struct gl_context *ctx, GLuint mesaFormat)
{
- GLint stride;
-
switch (mesaFormat) {
#if FEATURE_texture_fxt1
case MESA_FORMAT_RGB_FXT1:
+ return GL_COMPRESSED_RGB_FXT1_3DFX;
case MESA_FORMAT_RGBA_FXT1:
- stride = ((width + 7) / 8) * 16; /* 16 bytes per 8x4 tile */
- break;
+ 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:
- stride = ((width + 3) / 4) * 8; /* 8 bytes per 4x4 tile */
- break;
+ return GL_COMPRESSED_RGBA_S3TC_DXT1_EXT;
case MESA_FORMAT_RGBA_DXT3:
+ return GL_COMPRESSED_RGBA_S3TC_DXT3_EXT;
case MESA_FORMAT_RGBA_DXT5:
- stride = ((width + 3) / 4) * 16; /* 16 bytes per 4x4 tile */
- break;
+ 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(NULL, "bad mesaFormat in _mesa_compressed_row_stride");
+ _mesa_problem(ctx, "Unexpected mesa texture format in"
+ " _mesa_compressed_format_to_glenum()");
return 0;
}
-
- return stride;
}
/*
* Return the address of the pixel at (col, row, img) in a
* compressed texture image.
- * \param col, row, img - image position (3D)
+ * \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
+ * \param width - image width (stride) in pixels
* \param image - the image address
- * \return address of pixel at (row, col)
+ * \return address of pixel at (row, col, img)
*/
GLubyte *
_mesa_compressed_image_address(GLint col, GLint row, GLint img,
- GLuint mesaFormat,
+ gl_format mesaFormat,
GLsizei width, const GLubyte *image)
{
- GLubyte *addr;
+ /* XXX only 2D images implemented, not 3D */
+ const GLuint blockSize = _mesa_get_format_bytes(mesaFormat);
+ GLuint bw, bh;
+ GLint offset;
- (void) img;
+ _mesa_get_format_block_size(mesaFormat, &bw, &bh);
- /* We try to spot a "complete" subtexture "above" ROW, COL;
- * this texture is given by appropriate rounding of WIDTH x ROW.
- * Then we just add the amount left (usually on the left).
- *
- * Example for X*Y microtiles (Z bytes each)
- * offset = Z * (((width + X - 1) / X) * (row / Y) + col / X);
- */
+ ASSERT(col % bw == 0);
+ ASSERT(row % bh == 0);
- switch (mesaFormat) {
-#if FEATURE_texture_fxt1
- case MESA_FORMAT_RGB_FXT1:
- case MESA_FORMAT_RGBA_FXT1:
- addr = (GLubyte *) image + 16 * (((width + 7) / 8) * (row / 4) + col / 8);
- break;
-#endif
-#if FEATURE_texture_s3tc
- case MESA_FORMAT_RGB_DXT1:
- case MESA_FORMAT_RGBA_DXT1:
- addr = (GLubyte *) image + 8 * (((width + 3) / 4) * (row / 4) + col / 4);
- break;
- case MESA_FORMAT_RGBA_DXT3:
- case MESA_FORMAT_RGBA_DXT5:
- addr = (GLubyte *) image + 16 * (((width + 3) / 4) * (row / 4) + col / 4);
- break;
-#endif
- default:
- _mesa_problem(NULL, "bad mesaFormat in _mesa_compressed_image_address");
- addr = NULL;
- }
+ offset = ((width + bw - 1) / bw) * (row / bh) + col / bw;
+ offset *= blockSize;
- return addr;
+ return (GLubyte *) image + offset;
}