/*
* Mesa 3-D graphics library
*
* Copyright 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
* THE AUTHORS OR COPYRIGHT HOLDERS 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.
*/
/**
* Code to convert compressed/paletted texture images to ordinary images.
* See the GL_OES_compressed_paletted_texture spec at
* http://khronos.org/registry/gles/extensions/OES/OES_compressed_paletted_texture.txt
*
* XXX this makes it impossible to add hardware support...
*/
#include "glheader.h"
#include "context.h"
#include "mtypes.h"
#include "imports.h"
#include "pixelstore.h"
#include "texcompress_cpal.h"
#include "teximage.h"
static const struct cpal_format_info {
GLenum cpal_format;
GLenum format;
GLenum type;
GLuint palette_size;
GLuint size;
} formats[] = {
{ GL_PALETTE4_RGB8_OES, GL_RGB, GL_UNSIGNED_BYTE, 16, 3 },
{ GL_PALETTE4_RGBA8_OES, GL_RGBA, GL_UNSIGNED_BYTE, 16, 4 },
{ GL_PALETTE4_R5_G6_B5_OES, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, 16, 2 },
{ GL_PALETTE4_RGBA4_OES, GL_RGBA, GL_UNSIGNED_SHORT_4_4_4_4, 16, 2 },
{ GL_PALETTE4_RGB5_A1_OES, GL_RGBA, GL_UNSIGNED_SHORT_5_5_5_1, 16, 2 },
{ GL_PALETTE8_RGB8_OES, GL_RGB, GL_UNSIGNED_BYTE, 256, 3 },
{ GL_PALETTE8_RGBA8_OES, GL_RGBA, GL_UNSIGNED_BYTE, 256, 4 },
{ GL_PALETTE8_R5_G6_B5_OES, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, 256, 2 },
{ GL_PALETTE8_RGBA4_OES, GL_RGBA, GL_UNSIGNED_SHORT_4_4_4_4, 256, 2 },
{ GL_PALETTE8_RGB5_A1_OES, GL_RGBA, GL_UNSIGNED_SHORT_5_5_5_1, 256, 2 }
};
/**
* Get a color/entry from the palette.
*/
static GLuint
get_palette_entry(const struct cpal_format_info *info, const GLubyte *palette,
GLuint index, GLubyte *pixel)
{
memcpy(pixel
, palette
+ info
->size
* index
, info
->size
); return info->size;
}
/**
* Convert paletted texture to color texture.
*/
static void
paletted_to_color(const struct cpal_format_info *info, const GLubyte *palette,
const void *indices, GLuint num_pixels, GLubyte *image)
{
GLubyte *pix = image;
GLuint remain, i;
if (info->palette_size == 16) {
/* 4 bits per index */
const GLubyte *ind = (const GLubyte *) indices;
/* two pixels per iteration */
remain = num_pixels % 2;
for (i = 0; i < num_pixels / 2; i++) {
pix += get_palette_entry(info, palette, (ind[i] >> 4) & 0xf, pix);
pix += get_palette_entry(info, palette, ind[i] & 0xf, pix);
}
if (remain) {
get_palette_entry(info, palette, (ind[i] >> 4) & 0xf, pix);
}
}
else {
/* 8 bits per index */
const GLubyte *ind = (const GLubyte *) indices;
for (i = 0; i < num_pixels; i++)
pix += get_palette_entry(info, palette, ind[i], pix);
}
}
unsigned
_mesa_cpal_compressed_size(int level, GLenum internalFormat,
unsigned width, unsigned height)
{
const struct cpal_format_info *info;
const int num_levels = -level + 1;
int lvl;
unsigned w, h, expect_size;
if (internalFormat < GL_PALETTE4_RGB8_OES
|| internalFormat > GL_PALETTE8_RGB5_A1_OES) {
return 0;
}
info = &formats[internalFormat - GL_PALETTE4_RGB8_OES];
assert(info
->cpal_format
== internalFormat
);
expect_size = info->palette_size * info->size;
for (lvl = 0; lvl < num_levels; lvl++) {
w = width >> lvl;
if (!w)
w = 1;
h = height >> lvl;
if (!h)
h = 1;
if (info->palette_size == 16)
expect_size += (w * h + 1) / 2;
else
expect_size += w * h;
}
return expect_size;
}
/**
* Convert a call to glCompressedTexImage2D() where internalFormat is a
* compressed palette format into a regular GLubyte/RGBA glTexImage2D() call.
*/
void
_mesa_cpal_compressed_teximage2d(GLenum target, GLint level,
GLenum internalFormat,
GLsizei width, GLsizei height,
GLsizei imageSize, const void *palette)
{
const struct cpal_format_info *info;
GLint lvl, num_levels;
const GLubyte *indices;
GLint saved_align, align;
GET_CURRENT_CONTEXT(ctx);
/* By this point, the internalFormat should have been validated.
*/
assert(internalFormat
>= GL_PALETTE4_RGB8_OES
&& internalFormat <= GL_PALETTE8_RGB5_A1_OES);
info = &formats[internalFormat - GL_PALETTE4_RGB8_OES];
num_levels = -level + 1;
/* first image follows the palette */
indices = (const GLubyte *) palette + info->palette_size * info->size;
saved_align = ctx->Unpack.Alignment;
align = saved_align;
for (lvl = 0; lvl < num_levels; lvl++) {
GLsizei w, h;
GLuint num_texels;
GLubyte *image = NULL;
w = width >> lvl;
if (!w)
w = 1;
h = height >> lvl;
if (!h)
h = 1;
num_texels = w * h;
if (w * info->size % align) {
_mesa_PixelStorei(GL_UNPACK_ALIGNMENT, 1);
align = 1;
}
/* allocate and fill dest image buffer */
if (palette) {
image
= malloc(num_texels
* info
->size
); paletted_to_color(info, palette, indices, num_texels, image);
}
_mesa_TexImage2D(target, lvl, info->format, w, h, 0,
info->format, info->type, image);
/* advance index pointer to point to next src mipmap */
if (info->palette_size == 16)
indices += (num_texels + 1) / 2;
else
indices += num_texels;
}
if (saved_align != align)
_mesa_PixelStorei(GL_UNPACK_ALIGNMENT, saved_align);
}