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Diffstat (limited to 'src/mesa/main/texcompress.c')
-rw-r--r-- | src/mesa/main/texcompress.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/src/mesa/main/texcompress.c b/src/mesa/main/texcompress.c new file mode 100644 index 00000000000..0ba9aa9a4cd --- /dev/null +++ b/src/mesa/main/texcompress.c @@ -0,0 +1,159 @@ +/* $Id: texcompress.c,v 1.1 2002/09/27 02:45:38 brianp Exp $ */ + +/* + * Mesa 3-D graphics library + * Version: 4.1 + * + * Copyright (C) 1999-2002 Brian Paul All Rights Reserved. + * + * 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. + */ + + +#include "glheader.h" +#include "context.h" +#include "image.h" +#include "mem.h" +#include "texcompress.h" +#include "texformat.h" + + +/** + * Get the list of supported internal compression formats. + * \param formats - the results list (may be NULL) + * \return number of formats. + */ +GLuint +_mesa_get_compressed_formats( GLcontext *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 += 4; + } + } + } + return n; +} + + + +/** + * Return bytes of storage needed for the given texture size and compressed + * format. + * \param width, height, depth - texture size in texels + * \param texFormat - one of the compressed format enums + * \return size in bytes, or zero if bad texFormat + */ +GLuint +_mesa_compressed_texture_size( GLcontext *ctx, + GLsizei width, GLsizei height, GLsizei depth, + GLenum format ) +{ + GLuint size; + + switch (format) { + case GL_COMPRESSED_RGB_FXT1_3DFX: + case GL_COMPRESSED_RGBA_FXT1_3DFX: + /* round up to multiple of 4 */ + size = ((width + 7) / 8) * ((height + 3) / 4) * 16; + return size; + default: + _mesa_problem(ctx, "bad texformat in compressed_texture_size"); + return 0; + } +} + + +/* + * Compute the bytes per row in a compressed texture image. + */ +GLint +_mesa_compressed_row_stride(GLenum format, GLsizei width) +{ + GLint bytesPerTile, stride; + + switch (format) { + default: + return 0; + } + + stride = ((width + 3) / 4) * bytesPerTile; + 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 format - compressed image format + * \param width - image width + * \param image - the image address + * \return address of pixel at (row, col) + */ +GLubyte * +_mesa_compressed_image_address(GLint col, GLint row, GLint img, + GLenum format, + GLsizei width, const GLubyte *image) +{ + GLint bytesPerTile, stride; + GLubyte *addr; + + ASSERT((row & 3) == 0); + ASSERT((col & 3) == 0); + (void) img; + + switch (format) { + default: + return 0; + } + + stride = ((width + 3) / 4) * bytesPerTile; + + addr = (GLubyte *) image + (row / 4) * stride + (col / 4) * bytesPerTile; + return addr; +} + + + +/* + * \param srcRowStride - source stride, in pixels + */ +void +_mesa_compress_teximage( GLcontext *ctx, GLsizei width, GLsizei height, + GLenum srcFormat, const GLchan *source, GLint srcRowStride, + GLenum dstFormat, GLubyte *dest, GLint dstRowStride ) +{ + GLuint len = 0; + + switch (dstFormat) { + default: + _mesa_problem(ctx, "Bad dstFormat in _mesa_compress_teximage()"); + return; + } + + /* sanity check */ + ASSERT(len == _mesa_compressed_texture_size(ctx, width, height, + 1, dstFormat)); +} |