Tile cache functions.

src/mesa/pipe/softpipe/sp_tile_cache.c

@@ -0,0 +1,219 @@
+/**************************************************************************
+ * 
+ * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
+ * 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, sub license, 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 (including the
+ * next paragraph) 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 NON-INFRINGEMENT.
+ * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS 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.
+ * 
+ **************************************************************************/
+
+/**
+ * Framebuffer/surface tile caching.
+ *
+ * Author:
+ *    Brian Paul
+ */
+
+
+#include "sp_context.h"
+#include "sp_surface.h"
+#include "sp_tile_cache.h"
+
+
+#define NUM_ENTRIES 20
+
+
+/** XXX move these */
+#define MAX_WIDTH 2048
+#define MAX_HEIGHT 2048
+
+
+struct softpipe_tile_cache
+{
+   struct softpipe_cached_tile entries[NUM_ENTRIES];
+   uint clear_flags[(MAX_WIDTH / TILE_SIZE) * (MAX_HEIGHT / TILE_SIZE) / 32];
+};
+
+
+/**
+ * Return the position in the cache for the tile that contains win pos (x,y).
+ * We currently use a direct mapped cache so this is like a hack key.
+ * At some point we should investige something more sophisticated, like
+ * a LRU replacement policy.
+ */
+#define CACHE_POS(x, y) \
+   (((x) / TILE_SIZE + ((y) / TILE_SIZE) * 5) % NUM_ENTRIES)
+
+
+
+static uint
+is_clear_flag_set(const uint *bitvec, int x, int y)
+{
+   int pos, bit;
+   x /= TILE_SIZE;
+   y /= TILE_SIZE;
+   pos = y * (MAX_WIDTH / TILE_SIZE) + x;
+   bit = bitvec[pos / 32] & (1 << (pos & 31));
+   return bit;
+}
+   
+
+static void
+clear_clear_flag(uint *bitvec, int x, int y)
+{
+   int pos;
+   x /= TILE_SIZE;
+   y /= TILE_SIZE;
+   pos = y * (MAX_WIDTH / TILE_SIZE) + x;
+   bitvec[pos / 32] &= ~(1 << (pos & 31));
+}
+   
+
+struct softpipe_tile_cache *
+sp_create_tile_cache(void)
+{
+   struct softpipe_tile_cache *tc;
+   uint pos;
+
+   tc = calloc(1, sizeof(*tc));
+   if (tc) {
+      for (pos = 0; pos < NUM_ENTRIES; pos++) {
+         tc->entries[pos].x =
+         tc->entries[pos].y = -1;
+      }
+   }
+   return tc;
+}
+
+
+void
+sp_destroy_tile_cache(struct softpipe_tile_cache *tc)
+{
+   uint pos;
+   for (pos = 0; pos < NUM_ENTRIES; pos++) {
+      assert(tc->entries[pos].x < 0);
+   }
+   free(tc);
+}
+
+
+
+void
+sp_flush_tile_cache(struct softpipe_surface *sps)
+{
+   struct softpipe_tile_cache *tc = sps->tc;
+   /*
+   struct softpipe_surface *zsurf = softpipe_surface(softpipe->zbuf);
+   */
+   int inuse = 0, pos;
+
+   for (pos = 0; pos < NUM_ENTRIES; pos++) {
+      struct softpipe_cached_tile *tile = tc->entries + pos;
+      if (tile->x >= 0) {
+         sps->surface.put_tile(&sps->surface,
+                               tile->x,
+                               tile->y,
+                               TILE_SIZE, TILE_SIZE,
+                               (float *) tile->data.color);
+         /*
+         sps->surface.put_tile(&zsurf->surface,
+                               tile->x,
+                               tile->y,
+                               TILE_SIZE, TILE_SIZE,
+                               (float *) tile->depth);
+         */
+
+         tile->x = tile->y = -1;  /* mark as empty */
+         inuse++;
+      }
+   }
+
+   printf("flushed tiles in use: %d\n", inuse);
+
+}
+
+
+struct softpipe_cached_tile *
+sp_get_cached_tile(struct softpipe_surface *sps, int x, int y)
+{
+   struct softpipe_tile_cache *tc = sps->tc;
+
+   /* tile pos in framebuffer: */
+   const int tile_x = x & ~(TILE_SIZE - 1);
+   const int tile_y = y & ~(TILE_SIZE - 1);
+
+   /* cache pos/entry: */
+   const int pos = CACHE_POS(x, y);
+   struct softpipe_cached_tile *tile = tc->entries + pos;
+
+   /*
+   printf("output %d, %d at pos %d\n", x, y, pos);
+   */
+
+   if (tile_x != tile->x ||
+       tile_y != tile->y) {
+
+      /*
+      printf("new tile at %d, %d, pos %d\n", tile_x, tile_y, pos);
+      */
+
+      if (tile->x != -1) {
+         /* put dirty tile back in framebuffer */
+         sps->surface.put_tile(&sps->surface, tile->x, tile->y,
+                               TILE_SIZE, TILE_SIZE, (float *) tile->data.color);
+      }
+
+      if (is_clear_flag_set(tc->clear_flags, x, y)) {
+         printf("clear tile\n");
+#if 0
+         uint i, j;
+         for (i = 0; i < TILE_SIZE; i++) {
+            for (j = 0; j < TILE_SIZE; j++) {
+               tile->data.color[i][j][0] = 0.5;
+               tile->data.color[i][j][1] = 0.5;
+               tile->data.color[i][j][2] = 0.5;
+               tile->data.color[i][j][3] = 0.5;
+            }
+         }
+#endif
+         memset(tile->data.color, 0, sizeof(tile->data.color));
+         clear_clear_flag(tc->clear_flags, x, y);
+      }
+      else {
+         /* get new tile from framebuffer */
+         sps->surface.get_tile(&sps->surface, tile_x, tile_y,
+                               TILE_SIZE, TILE_SIZE, (float *) tile->data.color);
+      }
+
+      tile->x = tile_x;
+      tile->y = tile_y;
+   }
+
+   return tile;
+}
+
+
+void
+sp_clear_tile_cache(struct softpipe_surface *sps, unsigned clearval)
+{
+   (void) clearval; /* XXX use this */
+   memset(sps->tc->clear_flags, 255, sizeof(sps->tc->clear_flags));
+}