1 /*
2 * Mesa 3-D graphics library
3 *
4 * Copyright 2008 VMware, Inc.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included
14 * in all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25 /**
26 * Code to convert compressed/paletted texture images to ordinary images.
27 * See the GL_OES_compressed_paletted_texture spec at
28 * http://khronos.org/registry/gles/extensions/OES/OES_compressed_paletted_texture.txt
29 *
30 * XXX this makes it impossible to add hardware support...
31 */
32
33
34 #include "glheader.h"
35 #include "context.h"
36 #include "mtypes.h"
37
38 #include "pixelstore.h"
39 #include "texcompress_cpal.h"
40 #include "teximage.h"
41
42
43 static const struct cpal_format_info {
44 GLenum cpal_format;
45 GLenum format;
46 GLenum type;
47 GLuint palette_size;
48 GLuint size;
49 } formats[] = {
50 { GL_PALETTE4_RGB8_OES, GL_RGB, GL_UNSIGNED_BYTE, 16, 3 },
51 { GL_PALETTE4_RGBA8_OES, GL_RGBA, GL_UNSIGNED_BYTE, 16, 4 },
52 { GL_PALETTE4_R5_G6_B5_OES, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, 16, 2 },
53 { GL_PALETTE4_RGBA4_OES, GL_RGBA, GL_UNSIGNED_SHORT_4_4_4_4, 16, 2 },
54 { GL_PALETTE4_RGB5_A1_OES, GL_RGBA, GL_UNSIGNED_SHORT_5_5_5_1, 16, 2 },
55 { GL_PALETTE8_RGB8_OES, GL_RGB, GL_UNSIGNED_BYTE, 256, 3 },
56 { GL_PALETTE8_RGBA8_OES, GL_RGBA, GL_UNSIGNED_BYTE, 256, 4 },
57 { GL_PALETTE8_R5_G6_B5_OES, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, 256, 2 },
58 { GL_PALETTE8_RGBA4_OES, GL_RGBA, GL_UNSIGNED_SHORT_4_4_4_4, 256, 2 },
59 { GL_PALETTE8_RGB5_A1_OES, GL_RGBA, GL_UNSIGNED_SHORT_5_5_5_1, 256, 2 }
60 };
61
62
63 /**
64 * Get a color/entry from the palette.
65 */
66 static GLuint
get_palette_entry(const struct cpal_format_info * info,const GLubyte * palette,GLuint index,GLubyte * pixel)67 get_palette_entry(const struct cpal_format_info *info, const GLubyte *palette,
68 GLuint index, GLubyte *pixel)
69 {
70 memcpy(pixel, palette + info->size * index, info->size);
71 return info->size;
72 }
73
74
75 /**
76 * Convert paletted texture to color texture.
77 */
78 static void
paletted_to_color(const struct cpal_format_info * info,const GLubyte * palette,const void * indices,GLuint num_pixels,GLubyte * image)79 paletted_to_color(const struct cpal_format_info *info, const GLubyte *palette,
80 const void *indices, GLuint num_pixels, GLubyte *image)
81 {
82 GLubyte *pix = image;
83 GLuint remain, i;
84
85 if (info->palette_size == 16) {
86 /* 4 bits per index */
87 const GLubyte *ind = (const GLubyte *) indices;
88
89 /* two pixels per iteration */
90 remain = num_pixels % 2;
91 for (i = 0; i < num_pixels / 2; i++) {
92 pix += get_palette_entry(info, palette, (ind[i] >> 4) & 0xf, pix);
93 pix += get_palette_entry(info, palette, ind[i] & 0xf, pix);
94 }
95 if (remain) {
96 get_palette_entry(info, palette, (ind[i] >> 4) & 0xf, pix);
97 }
98 }
99 else {
100 /* 8 bits per index */
101 const GLubyte *ind = (const GLubyte *) indices;
102 for (i = 0; i < num_pixels; i++)
103 pix += get_palette_entry(info, palette, ind[i], pix);
104 }
105 }
106
107 unsigned
_mesa_cpal_compressed_size(int level,GLenum internalFormat,unsigned width,unsigned height)108 _mesa_cpal_compressed_size(int level, GLenum internalFormat,
109 unsigned width, unsigned height)
110 {
111 const struct cpal_format_info *info;
112 const int num_levels = -level + 1;
113 int lvl;
114 unsigned w, h, expect_size;
115
116 if (internalFormat < GL_PALETTE4_RGB8_OES
117 || internalFormat > GL_PALETTE8_RGB5_A1_OES) {
118 return 0;
119 }
120
121 info = &formats[internalFormat - GL_PALETTE4_RGB8_OES];
122 assert(info->cpal_format == internalFormat);
123
124 expect_size = info->palette_size * info->size;
125 for (lvl = 0; lvl < num_levels; lvl++) {
126 w = width >> lvl;
127 if (!w)
128 w = 1;
129 h = height >> lvl;
130 if (!h)
131 h = 1;
132
133 if (info->palette_size == 16)
134 expect_size += (w * h + 1) / 2;
135 else
136 expect_size += w * h;
137 }
138
139 return expect_size;
140 }
141
142
143 /**
144 * Convert a call to glCompressedTexImage2D() where internalFormat is a
145 * compressed palette format into a regular GLubyte/RGBA glTexImage2D() call.
146 */
147 void
_mesa_cpal_compressed_teximage2d(GLenum target,GLint level,GLenum internalFormat,GLsizei width,GLsizei height,GLsizei imageSize,const void * palette)148 _mesa_cpal_compressed_teximage2d(GLenum target, GLint level,
149 GLenum internalFormat,
150 GLsizei width, GLsizei height,
151 GLsizei imageSize, const void *palette)
152 {
153 const struct cpal_format_info *info;
154 GLint lvl, num_levels;
155 const GLubyte *indices;
156 GLint saved_align, align;
157 GET_CURRENT_CONTEXT(ctx);
158
159 /* By this point, the internalFormat should have been validated.
160 */
161 assert(internalFormat >= GL_PALETTE4_RGB8_OES
162 && internalFormat <= GL_PALETTE8_RGB5_A1_OES);
163
164 info = &formats[internalFormat - GL_PALETTE4_RGB8_OES];
165
166 num_levels = -level + 1;
167
168 /* first image follows the palette */
169 indices = (const GLubyte *) palette + info->palette_size * info->size;
170
171 saved_align = ctx->Unpack.Alignment;
172 align = saved_align;
173
174 for (lvl = 0; lvl < num_levels; lvl++) {
175 GLsizei w, h;
176 GLuint num_texels;
177 GLubyte *image = NULL;
178
179 w = width >> lvl;
180 if (!w)
181 w = 1;
182 h = height >> lvl;
183 if (!h)
184 h = 1;
185 num_texels = w * h;
186 if (w * info->size % align) {
187 _mesa_PixelStorei(GL_UNPACK_ALIGNMENT, 1);
188 align = 1;
189 }
190
191 /* allocate and fill dest image buffer */
192 if (palette) {
193 image = malloc(num_texels * info->size);
194 paletted_to_color(info, palette, indices, num_texels, image);
195 }
196
197 _mesa_TexImage2D(target, lvl, info->format, w, h, 0,
198 info->format, info->type, image);
199 free(image);
200
201 /* advance index pointer to point to next src mipmap */
202 if (info->palette_size == 16)
203 indices += (num_texels + 1) / 2;
204 else
205 indices += num_texels;
206 }
207
208 if (saved_align != align)
209 _mesa_PixelStorei(GL_UNPACK_ALIGNMENT, saved_align);
210 }
211