mutter/clutter/cogl/pango/cogl-pango-glyph-cache.c
Neil Roberts 9ea2567a2f cogl-atlas-texture: Don't let textures be destroyed during migration
If an atlas texture's last reference is held by the journal or by the
last flushed pipeline then if an atlas migration is started it can
cause a crash. This is because the atlas migration will cause a
journal flush and can sometimes change the current pipeline which
means that the texture would be destroyed during migration.

This patch adds an extra 'post_reorganize' callback to the existing
'reorganize' callback (which is now renamed to 'pre_reorganize'). The
pre_reorganize callback is now called before the atlas grabs a list of
the current textures instead of after so that it doesn't matter if the
journal flush destroys some of those textures. The pre_reorganize
callback for CoglAtlasTexture grabs a reference to all of the textures
so that they can not be destroyed when the migration changes the
pipeline. In the post_reorganize callback the reference is removed
again.

http://bugzilla.clutter-project.org/show_bug.cgi?id=2538
2011-02-17 13:39:30 +00:00

309 lines
9.1 KiB
C

/*
* Clutter.
*
* An OpenGL based 'interactive canvas' library.
*
* Authored By Matthew Allum <mallum@openedhand.com>
*
* Copyright (C) 2008 OpenedHand
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses>.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <glib.h>
#include "cogl-pango-glyph-cache.h"
#include "cogl-pango-private.h"
#include "cogl/cogl-atlas.h"
#include "cogl/cogl-callback-list.h"
typedef struct _CoglPangoGlyphCacheKey CoglPangoGlyphCacheKey;
struct _CoglPangoGlyphCache
{
/* Hash table to quickly check whether a particular glyph in a
particular font is already cached */
GHashTable *hash_table;
/* List of CoglAtlases */
GSList *atlases;
/* List of callbacks to invoke when an atlas is reorganized */
CoglCallbackList reorganize_callbacks;
/* True if some of the glyphs are dirty. This is used as an
optimization in _cogl_pango_glyph_cache_set_dirty_glyphs to avoid
iterating the hash table if we know none of them are dirty */
gboolean has_dirty_glyphs;
};
struct _CoglPangoGlyphCacheKey
{
PangoFont *font;
PangoGlyph glyph;
};
static void
cogl_pango_glyph_cache_value_free (CoglPangoGlyphCacheValue *value)
{
cogl_handle_unref (value->texture);
g_slice_free (CoglPangoGlyphCacheValue, value);
}
static void
cogl_pango_glyph_cache_key_free (CoglPangoGlyphCacheKey *key)
{
g_object_unref (key->font);
g_slice_free (CoglPangoGlyphCacheKey, key);
}
static guint
cogl_pango_glyph_cache_hash_func (gconstpointer key)
{
const CoglPangoGlyphCacheKey *cache_key
= (const CoglPangoGlyphCacheKey *) key;
/* Generate a number affected by both the font and the glyph
number. We can safely directly compare the pointers because the
key holds a reference to the font so it is not possible that a
different font will have the same memory address */
return GPOINTER_TO_UINT (cache_key->font) ^ cache_key->glyph;
}
static gboolean
cogl_pango_glyph_cache_equal_func (gconstpointer a,
gconstpointer b)
{
const CoglPangoGlyphCacheKey *key_a
= (const CoglPangoGlyphCacheKey *) a;
const CoglPangoGlyphCacheKey *key_b
= (const CoglPangoGlyphCacheKey *) b;
/* We can safely directly compare the pointers for the fonts because
the key holds a reference to the font so it is not possible that
a different font will have the same memory address */
return key_a->font == key_b->font
&& key_a->glyph == key_b->glyph;
}
CoglPangoGlyphCache *
cogl_pango_glyph_cache_new (void)
{
CoglPangoGlyphCache *cache;
cache = g_malloc (sizeof (CoglPangoGlyphCache));
cache->hash_table = g_hash_table_new_full
(cogl_pango_glyph_cache_hash_func,
cogl_pango_glyph_cache_equal_func,
(GDestroyNotify) cogl_pango_glyph_cache_key_free,
(GDestroyNotify) cogl_pango_glyph_cache_value_free);
cache->atlases = NULL;
_cogl_callback_list_init (&cache->reorganize_callbacks);
cache->has_dirty_glyphs = FALSE;
return cache;
}
void
cogl_pango_glyph_cache_clear (CoglPangoGlyphCache *cache)
{
g_slist_foreach (cache->atlases, (GFunc) cogl_object_unref, NULL);
g_slist_free (cache->atlases);
cache->atlases = NULL;
cache->has_dirty_glyphs = FALSE;
g_hash_table_remove_all (cache->hash_table);
}
void
cogl_pango_glyph_cache_free (CoglPangoGlyphCache *cache)
{
cogl_pango_glyph_cache_clear (cache);
g_hash_table_unref (cache->hash_table);
_cogl_callback_list_destroy (&cache->reorganize_callbacks);
g_free (cache);
}
static void
cogl_pango_glyph_cache_update_position_cb (void *user_data,
CoglHandle new_texture,
const CoglRectangleMapEntry *rect)
{
CoglPangoGlyphCacheValue *value = user_data;
float tex_width, tex_height;
if (value->texture)
cogl_handle_unref (value->texture);
value->texture = cogl_handle_ref (new_texture);
tex_width = cogl_texture_get_width (new_texture);
tex_height = cogl_texture_get_height (new_texture);
value->tx1 = rect->x / tex_width;
value->ty1 = rect->y / tex_height;
value->tx2 = (rect->x + value->draw_width) / tex_width;
value->ty2 = (rect->y + value->draw_height) / tex_height;
value->tx_pixel = rect->x;
value->ty_pixel = rect->y;
/* The glyph has changed position so it will need to be redrawn */
value->dirty = TRUE;
}
static void
cogl_pango_glyph_cache_reorganize_cb (void *user_data)
{
CoglPangoGlyphCache *cache = user_data;
_cogl_callback_list_invoke (&cache->reorganize_callbacks);
}
CoglPangoGlyphCacheValue *
cogl_pango_glyph_cache_lookup (CoglPangoGlyphCache *cache,
gboolean create,
PangoFont *font,
PangoGlyph glyph)
{
CoglPangoGlyphCacheKey lookup_key;
CoglPangoGlyphCacheValue *value;
lookup_key.font = font;
lookup_key.glyph = glyph;
value = g_hash_table_lookup (cache->hash_table, &lookup_key);
if (create && value == NULL)
{
CoglPangoGlyphCacheKey *key;
PangoRectangle ink_rect;
CoglAtlas *atlas = NULL;
GSList *l;
pango_font_get_glyph_extents (font, glyph, &ink_rect, NULL);
pango_extents_to_pixels (&ink_rect, NULL);
value = g_slice_new (CoglPangoGlyphCacheValue);
value->texture = COGL_INVALID_HANDLE;
value->draw_x = ink_rect.x;
value->draw_y = ink_rect.y;
value->draw_width = ink_rect.width;
value->draw_height = ink_rect.height;
value->dirty = TRUE;
/* Look for an atlas that can reserve the space */
for (l = cache->atlases; l; l = l->next)
if (_cogl_atlas_reserve_space (l->data,
ink_rect.width + 1, ink_rect.height + 1,
value))
{
atlas = l->data;
break;
}
/* If we couldn't find one then start a new atlas */
if (atlas == NULL)
{
atlas = _cogl_atlas_new (COGL_PIXEL_FORMAT_A_8,
TRUE,
cogl_pango_glyph_cache_update_position_cb);
COGL_NOTE (ATLAS, "Created new atlas for glyphs: %p", atlas);
/* If we still can't reserve space then something has gone
seriously wrong so we'll just give up */
if (!_cogl_atlas_reserve_space (atlas,
ink_rect.width + 1,
ink_rect.height + 1, value))
{
cogl_object_unref (atlas);
cogl_pango_glyph_cache_value_free (value);
return NULL;
}
_cogl_atlas_add_reorganize_callback
(atlas, cogl_pango_glyph_cache_reorganize_cb, NULL, cache);
cache->atlases = g_slist_prepend (cache->atlases, atlas);
}
key = g_slice_new (CoglPangoGlyphCacheKey);
key->font = g_object_ref (font);
key->glyph = glyph;
g_hash_table_insert (cache->hash_table, key, value);
cache->has_dirty_glyphs = TRUE;
}
return value;
}
static void
_cogl_pango_glyph_cache_set_dirty_glyphs_cb (gpointer key_ptr,
gpointer value_ptr,
gpointer user_data)
{
CoglPangoGlyphCacheKey *key = key_ptr;
CoglPangoGlyphCacheValue *value = value_ptr;
CoglPangoGlyphCacheDirtyFunc func = user_data;
if (value->dirty)
{
func (key->font, key->glyph, value);
value->dirty = FALSE;
}
}
void
_cogl_pango_glyph_cache_set_dirty_glyphs (CoglPangoGlyphCache *cache,
CoglPangoGlyphCacheDirtyFunc func)
{
/* If we know that there are no dirty glyphs then we can shortcut
out early */
if (!cache->has_dirty_glyphs)
return;
g_hash_table_foreach (cache->hash_table,
_cogl_pango_glyph_cache_set_dirty_glyphs_cb,
func);
cache->has_dirty_glyphs = FALSE;
}
void
_cogl_pango_glyph_cache_add_reorganize_callback (CoglPangoGlyphCache *cache,
CoglCallbackListFunc func,
void *user_data)
{
_cogl_callback_list_add (&cache->reorganize_callbacks, func, user_data);
}
void
_cogl_pango_glyph_cache_remove_reorganize_callback (CoglPangoGlyphCache *cache,
CoglCallbackListFunc func,
void *user_data)
{
_cogl_callback_list_remove (&cache->reorganize_callbacks, func, user_data);
}