2 * $Id: texcache.c,v 1.4 2006-03-16 12:42:39 nkeynes Exp $
4 * Texture cache. Responsible for maintaining a working set of OpenGL
8 * Copyright (c) 2005 Nathan Keynes.
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
22 #include "pvr2/pvr2.h"
24 /** Specifies the maximum number of OpenGL
25 * textures we're willing to have open at a time. If more are
26 * needed, textures will be evicted in LRU order.
28 #define MAX_TEXTURES 64
34 * find entry by texture_addr
36 * move entry to tail of lru list
40 typedef signed short texcache_entry_index;
41 #define EMPTY_ENTRY 0xFF
43 static texcache_entry_index texcache_free_ptr = 0;
44 static GLuint texcache_free_list[MAX_TEXTURES];
46 typedef struct texcache_entry {
47 uint32_t texture_addr;
48 int width, height, mode;
50 texcache_entry_index next;
54 static uint8_t texcache_page_lookup[PVR2_RAM_PAGES];
55 static uint32_t texcache_ref_counter;
56 static struct texcache_entry texcache_active_list[MAX_TEXTURES];
59 * Initialize the texture cache.
64 for( i=0; i<PVR2_RAM_PAGES; i++ ) {
65 texcache_page_lookup[i] = EMPTY_ENTRY;
67 for( i=0; i<MAX_TEXTURES; i++ ) {
68 texcache_free_list[i] = i;
70 texcache_free_ptr = 0;
71 texcache_ref_counter = 0;
75 * Setup the initial texture ids (must be called after the GL context is
78 void texcache_gl_init( )
81 GLuint texids[MAX_TEXTURES];
83 glGenTextures( MAX_TEXTURES, texids );
84 for( i=0; i<MAX_TEXTURES; i++ ) {
85 texcache_active_list[i].texture_id = texids[i];
90 * Flush all textures from the cache, returning them to the free list.
92 void texcache_flush( )
95 /* clear structures */
96 for( i=0; i<PVR2_RAM_PAGES; i++ ) {
97 texcache_page_lookup[i] = EMPTY_ENTRY;
99 for( i=0; i<MAX_TEXTURES; i++ ) {
100 texcache_free_list[i] = i;
102 texcache_free_ptr = 0;
103 texcache_ref_counter = 0;
107 * Flush all textures and delete. The cache will be non-functional until
108 * the next call to texcache_init(). This would typically be done if
109 * switching GL targets.
111 void texcache_shutdown( )
113 GLuint texids[MAX_TEXTURES];
117 for( i=0; i<MAX_TEXTURES; i++ ) {
118 texids[i] = texcache_active_list[i].texture_id;
120 glDeleteTextures( MAX_TEXTURES, texids );
124 * Evict all textures contained in the page identified by a texture address.
126 void texcache_invalidate_page( uint32_t texture_addr ) {
127 uint32_t texture_page = texture_addr >> 12;
128 texcache_entry_index idx = texcache_page_lookup[texture_page];
129 if( idx == EMPTY_ENTRY )
131 assert( texcache_free_ptr >= 0 );
133 texcache_entry_t entry = &texcache_active_list[idx];
136 texcache_free_list[texcache_free_ptr] = idx;
138 entry->next = EMPTY_ENTRY;
139 } while( idx != EMPTY_ENTRY );
140 texcache_page_lookup[texture_page] = EMPTY_ENTRY;
144 * Evict a single texture from the cache.
145 * @return the slot of the evicted texture.
147 static texcache_entry_index texcache_evict( void )
149 /* Full table scan - take over the entry with the lowest lru value */
150 texcache_entry_index slot = 0;
151 int lru_value = texcache_active_list[0].lru_count;
153 for( i=1; i<MAX_TEXTURES; i++ ) {
154 /* FIXME: account for rollover */
155 if( texcache_active_list[i].lru_count < lru_value ) {
157 lru_value = texcache_active_list[i].lru_count;
161 /* Remove the selected slot from the lookup table */
162 uint32_t evict_page = texcache_active_list[slot].texture_addr;
163 texcache_entry_index replace_next = texcache_active_list[slot].next;
164 texcache_active_list[slot].next = EMPTY_ENTRY; /* Just for safety */
165 if( texcache_page_lookup[evict_page] == slot ) {
166 texcache_page_lookup[evict_page] = replace_next;
168 texcache_entry_index idx = texcache_page_lookup[evict_page];
169 texcache_entry_index next;
171 next = texcache_active_list[idx].next;
173 texcache_active_list[idx].next = replace_next;
177 } while( next != EMPTY_ENTRY );
182 static void detwiddle_pal8_to_24(int x1, int y1, int size, int totsize,
183 char **in, uint32_t *out, uint32_t *pal) {
185 out[y1 * totsize + x1] = pal[**in];
189 detwiddle_pal8_to_24(x1, y1, ns, totsize, in, out, pal);
190 detwiddle_pal8_to_24(x1, y1+ns, ns, totsize, in, out, pal);
191 detwiddle_pal8_to_24(x1+ns, y1, ns, totsize, in, out, pal);
192 detwiddle_pal8_to_24(x1+ns, y1+ns, ns, totsize, in, out, pal);
198 * Load texture data from the given address and parameters into the currently
199 * bound OpenGL texture.
201 static texcache_load_texture( uint32_t texture_addr, int width, int height,
203 uint32_t bytes = width * height;
205 GLint intFormat, format, type;
206 int tex_format = mode & PVR2_TEX_FORMAT_MASK;
208 if( tex_format == PVR2_TEX_FORMAT_IDX8 ||
209 tex_format == PVR2_TEX_FORMAT_IDX4 ) {
210 switch( MMIO_READ( PVR2, PALETTECFG ) & 0x03 ) {
211 case 0: /* ARGB1555 */
212 intFormat = GL_RGB5_A1;
214 type = GL_UNSIGNED_SHORT_5_5_5_1;
219 type = GL_UNSIGNED_SHORT_5_6_5;
222 intFormat = GL_RGBA4;
224 type = GL_UNSIGNED_SHORT_4_4_4_4;
227 intFormat = GL_RGBA8;
229 type = GL_UNSIGNED_INT_8_8_8_8_REV;
234 if( tex_format == PVR2_TEX_FORMAT_IDX8 ) {
235 unsigned char data[bytes<<shift];
236 int bank = (mode >> 25) &0x03;
237 char *palette = mmio_region_PVR2PAL.mem + (bank * (256 << shift));
242 pvr2_vram64_read( tmp, texture_addr, bytes );
243 detwiddle_pal8_to_24( 0, 0, width, width, &p,
244 (uint32_t *)data, (uint32_t *)palette );
246 pvr2_vram64_read( &data, texture_addr, bytes );
247 for( i=bytes-1; i>=0; i-- ) {
249 ((uint16_t *)data)[i] = ((uint16_t *)palette)[ch];
252 /* TODO: Detwiddle */
253 glTexImage2D( GL_TEXTURE_2D, 0, intFormat, width, height, 0, format, type,
258 switch( tex_format ) {
259 case PVR2_TEX_FORMAT_ARGB1555:
261 intFormat = GL_RGB5_A1;
263 type = GL_UNSIGNED_SHORT_5_5_5_1;
265 case PVR2_TEX_FORMAT_RGB565:
269 type = GL_UNSIGNED_SHORT_5_6_5;
271 case PVR2_TEX_FORMAT_ARGB4444:
273 intFormat = GL_RGBA4;
275 type = GL_UNSIGNED_SHORT_4_4_4_4;
277 case PVR2_TEX_FORMAT_YUV422:
278 ERROR( "YUV textures not supported" );
280 case PVR2_TEX_FORMAT_BUMPMAP:
281 ERROR( "Bumpmap not supported" );
283 case PVR2_TEX_FORMAT_IDX4:
286 intFormat = GL_INTENSITY4;
287 format = GL_COLOR_INDEX;
288 type = GL_UNSIGNED_BYTE;
291 case PVR2_TEX_FORMAT_IDX8:
292 intFormat = GL_INTENSITY8;
293 format = GL_COLOR_INDEX;
294 type = GL_UNSIGNED_BYTE;
299 unsigned char data[bytes];
300 /* load data from image, detwiddling/uncompressing as required */
301 if( PVR2_TEX_IS_COMPRESSED(mode) ) {
302 ERROR( "VQ Compression not supported" );
304 pvr2_vram64_read( &data, texture_addr, bytes );
305 if( PVR2_TEX_IS_TWIDDLED(mode) ) {
311 glTexImage2D( GL_TEXTURE_2D, 0, intFormat, width, height, 0, format, type,
314 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
315 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
319 * Return a texture ID for the texture specified at the supplied address
320 * and given parameters (the same sequence of bytes could in theory have
321 * multiple interpretations). We use the texture address as the primary
322 * index, but allow for multiple instances at each address. The texture
323 * will be bound to the GL_TEXTURE_2D target before being returned.
325 * If the texture has already been bound, return the ID to which it was
326 * bound. Otherwise obtain an unused texture ID and set it up appropriately.
328 GLuint texcache_get_texture( uint32_t texture_addr, int width, int height,
331 uint32_t texture_page = texture_addr >> 12;
332 texcache_entry_index idx = texcache_page_lookup[texture_page];
333 while( idx != EMPTY_ENTRY ) {
334 texcache_entry_t entry = &texcache_active_list[idx];
335 if( entry->texture_addr == texture_addr &&
336 entry->mode == mode &&
337 entry->width == width &&
338 entry->height == height ) {
339 entry->lru_count = texcache_ref_counter++;
340 glBindTexture( GL_TEXTURE_2D, entry->texture_id );
341 return entry->texture_id;
346 /* Not found - check the free list */
349 if( texcache_free_ptr < MAX_TEXTURES ) {
350 slot = texcache_free_list[texcache_free_ptr++];
352 slot = texcache_evict();
355 /* Construct new entry */
356 texcache_active_list[slot].texture_addr = texture_addr;
357 texcache_active_list[slot].width = width;
358 texcache_active_list[slot].height = height;
359 texcache_active_list[slot].mode = mode;
360 texcache_active_list[slot].lru_count = texcache_ref_counter++;
362 /* Add entry to the lookup table */
363 texcache_active_list[slot].next = texcache_page_lookup[texture_page];
364 texcache_page_lookup[texture_page] = slot;
366 /* Construct the GL texture */
367 glBindTexture( GL_TEXTURE_2D, texcache_active_list[slot].texture_id );
368 texcache_load_texture( texture_addr, width, height, mode );
370 return texcache_active_list[slot].texture_id;
.