mutter/cogl/cogl-atlas.c
Neil Roberts 9aea72fab5 Allow multiple CoglAtlases for textures
Previously Cogl would only ever use one atlas for textures and if it
reached the maximum texture size then all other new textures would get
their own GL texture. This patch makes it so that we create as many
atlases as needed. This should avoid breaking up some batches and it
will be particularly good if we switch to always using multi-texturing
with a default shader that selects between multiple atlases using a
vertex attribute.

Whenever a new atlas is created it is stored in a GSList on the
context. A weak weference is taken on the atlas using
cogl_object_set_user_data so that it can be removed from the list when
the atlas is destroyed. The atlas textures themselves take a reference
to the atlas and this is the only thing that keeps the atlas
alive. This means that once the atlas becomes empty it will
automatically be destroyed.

All of the COGL_NOTEs pertaining to atlases are now prefixed with the
atlas pointer to make it clearer which atlas is changing.
2010-12-13 18:59:41 +00:00

700 lines
24 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2010 Intel Corporation.
*
* 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, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*
* Authors:
* Neil Roberts <neil@linux.intel.com>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "cogl.h"
#include "cogl-atlas.h"
#include "cogl-rectangle-map.h"
#include "cogl-context.h"
#include "cogl-texture-private.h"
#include "cogl-texture-2d-private.h"
#include "cogl-texture-driver.h"
#include "cogl-pipeline-opengl-private.h"
#include "cogl-debug.h"
#include <stdlib.h>
#ifndef HAVE_COGL_GLES2
#define glGenFramebuffers ctx->drv.pf_glGenFramebuffers
#define glBindFramebuffer ctx->drv.pf_glBindFramebuffer
#define glFramebufferTexture2D ctx->drv.pf_glFramebufferTexture2D
#define glCheckFramebufferStatus ctx->drv.pf_glCheckFramebufferStatus
#define glDeleteFramebuffers ctx->drv.pf_glDeleteFramebuffers
#endif /* HAVE_COGL_GLES2 */
#ifndef GL_FRAMEBUFFER
#define GL_FRAMEBUFFER 0x8D40
#endif
#ifndef GL_FRAMEBUFFER_BINDING
#define GL_FRAMEBUFFER_BINDING 0x8CA6
#endif
#ifndef GL_COLOR_ATTACHMENT0
#define GL_COLOR_ATTACHMENT0 0x8CE0
#endif
#ifndef GL_FRAMEBUFFER_COMPLETE
#define GL_FRAMEBUFFER_COMPLETE 0x8CD5
#endif
static void _cogl_atlas_free (CoglAtlas *atlas);
COGL_OBJECT_INTERNAL_DEFINE (Atlas, atlas);
/* If we want to do mulitple blits from a texture (such as when
reorganizing the atlas) then it's quicker to download all of the
data once and upload multiple times from that. This struct is used
to keep the image data for a series of blits */
typedef struct _CoglAtlasBlitData
{
CoglHandle src_tex, dst_tex;
/* If we're using an FBO to blit, then FBO will be non-zero and
old_fbo will be the previous framebuffer binding */
GLuint fbo, old_fbo;
/* If we're not using an FBO then we g_malloc a buffer and copy the
complete texture data in */
unsigned char *image_data;
CoglPixelFormat format;
int bpp;
unsigned int src_height, src_width;
GLenum dst_gl_target;
} CoglAtlasBlitData;
static void
_cogl_atlas_blit_begin (CoglAtlasBlitData *data,
CoglHandle dst_tex,
CoglHandle src_tex)
{
GLenum src_gl_target;
GLuint src_gl_texture;
GLuint dst_gl_texture;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
data->dst_tex = dst_tex;
data->src_tex = src_tex;
data->fbo = 0;
/* If we can use an FBO then we don't need to download the data and
we can tell GL to blit directly between the textures */
if (cogl_features_available (COGL_FEATURE_OFFSCREEN) &&
!cogl_texture_is_sliced (dst_tex) &&
cogl_texture_get_gl_texture (src_tex, &src_gl_texture, &src_gl_target) &&
cogl_texture_get_gl_texture (dst_tex, &dst_gl_texture,
&data->dst_gl_target))
{
/* Ideally we would use the cogl-offscreen API here, but I'd
rather avoid creating a stencil renderbuffer which you can't
currently do */
/* Preserve the previous framebuffer binding so we don't trample
on cogl-offscreen */
data->old_fbo = 0;
GE( glGetIntegerv (GL_FRAMEBUFFER_BINDING, (GLint *) &data->old_fbo) );
_cogl_texture_set_filters (src_tex, GL_NEAREST, GL_NEAREST);
/* Create an FBO to read from the src texture */
GE( glGenFramebuffers (1, &data->fbo) );
GE( glBindFramebuffer (GL_FRAMEBUFFER, data->fbo) );
GE( glFramebufferTexture2D (GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
src_gl_target, src_gl_texture, 0) );
if (glCheckFramebufferStatus (GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
{
/* The FBO failed for whatever reason so we'll fallback to
reading the texture data */
GE( glBindFramebuffer (GL_FRAMEBUFFER, data->old_fbo) );
GE( glDeleteFramebuffers (1, &data->fbo) );
data->fbo = 0;
}
_cogl_bind_gl_texture_transient (data->dst_gl_target,
dst_gl_texture,
FALSE);
}
if (data->fbo)
COGL_NOTE (ATLAS, "Blit set up using an FBO");
else
{
/* We need to retrieve the entire texture data (there is no
glGetTexSubImage2D) */
data->format = cogl_texture_get_format (src_tex);
data->bpp = _cogl_get_format_bpp (data->format);
data->src_width = cogl_texture_get_width (src_tex);
data->src_height = cogl_texture_get_height (src_tex);
data->image_data = g_malloc (data->bpp * data->src_width *
data->src_height);
cogl_texture_get_data (src_tex, data->format,
data->src_width * data->bpp, data->image_data);
}
}
static void
_cogl_atlas_blit (CoglAtlasBlitData *data,
unsigned int src_x,
unsigned int src_y,
unsigned int dst_x,
unsigned int dst_y,
unsigned int width,
unsigned int height)
{
/* If we have an FBO then we can do a fast blit */
if (data->fbo)
GE( glCopyTexSubImage2D (data->dst_gl_target, 0, dst_x, dst_y, src_x, src_y,
width, height) );
else
cogl_texture_set_region (data->dst_tex,
src_x, src_y,
dst_x, dst_y,
width, height,
data->src_width, data->src_height,
data->format,
data->src_width * data->bpp,
data->image_data);
}
static void
_cogl_atlas_blit_end (CoglAtlasBlitData *data)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (data->fbo)
{
GE( glBindFramebuffer (GL_FRAMEBUFFER, data->old_fbo) );
GE( glDeleteFramebuffers (1, &data->fbo) );
}
else
g_free (data->image_data);
}
CoglAtlas *
_cogl_atlas_new (CoglPixelFormat texture_format,
CoglAtlasFlags flags,
CoglAtlasUpdatePositionCallback update_position_cb)
{
CoglAtlas *atlas = g_new (CoglAtlas, 1);
atlas->update_position_cb = update_position_cb;
atlas->map = NULL;
atlas->texture = NULL;
atlas->flags = flags;
atlas->texture_format = texture_format;
_cogl_callback_list_init (&atlas->reorganize_callbacks);
return _cogl_atlas_object_new (atlas);
}
static void
_cogl_atlas_free (CoglAtlas *atlas)
{
COGL_NOTE (ATLAS, "%p: Atlas destroyed", atlas);
if (atlas->texture)
cogl_handle_unref (atlas->texture);
if (atlas->map)
_cogl_rectangle_map_free (atlas->map);
_cogl_callback_list_destroy (&atlas->reorganize_callbacks);
g_free (atlas);
}
typedef struct _CoglAtlasRepositionData
{
/* The current user data for this texture */
void *user_data;
/* The old and new positions of the texture */
CoglRectangleMapEntry old_position;
CoglRectangleMapEntry new_position;
} CoglAtlasRepositionData;
static void
_cogl_atlas_migrate (CoglAtlas *atlas,
unsigned int n_textures,
CoglAtlasRepositionData *textures,
CoglHandle old_texture,
CoglHandle new_texture,
void *skip_user_data)
{
unsigned int i;
CoglAtlasBlitData blit_data;
/* If the 'disable migrate' flag is set then we won't actually copy
the textures to their new location. Instead we'll just invoke the
callback to update the position */
if ((atlas->flags & COGL_ATLAS_DISABLE_MIGRATION))
for (i = 0; i < n_textures; i++)
/* Update the texture position */
atlas->update_position_cb (textures[i].user_data,
new_texture,
&textures[i].new_position);
else
{
_cogl_atlas_blit_begin (&blit_data, new_texture, old_texture);
for (i = 0; i < n_textures; i++)
{
/* Skip the texture that is being added because it doesn't contain
any data yet */
if (textures[i].user_data != skip_user_data)
_cogl_atlas_blit (&blit_data,
textures[i].old_position.x,
textures[i].old_position.y,
textures[i].new_position.x,
textures[i].new_position.y,
textures[i].new_position.width,
textures[i].new_position.height);
/* Update the texture position */
atlas->update_position_cb (textures[i].user_data,
new_texture,
&textures[i].new_position);
}
_cogl_atlas_blit_end (&blit_data);
}
}
typedef struct _CoglAtlasGetRectanglesData
{
CoglAtlasRepositionData *textures;
/* Number of textures found so far */
unsigned int n_textures;
} CoglAtlasGetRectanglesData;
static void
_cogl_atlas_get_rectangles_cb (const CoglRectangleMapEntry *rectangle,
void *rect_data,
void *user_data)
{
CoglAtlasGetRectanglesData *data = user_data;
data->textures[data->n_textures].old_position = *rectangle;
data->textures[data->n_textures++].user_data = rect_data;
}
static void
_cogl_atlas_get_next_size (unsigned int *map_width,
unsigned int *map_height)
{
/* Double the size of the texture by increasing whichever dimension
is smaller */
if (*map_width < *map_height)
*map_width <<= 1;
else
*map_height <<= 1;
}
static void
_cogl_atlas_get_initial_size (CoglPixelFormat format,
unsigned int *map_width,
unsigned int *map_height)
{
unsigned int size;
GLenum gl_intformat;
GLenum gl_type;
_cogl_pixel_format_to_gl (format,
&gl_intformat,
NULL, /* gl_format */
&gl_type);
/* At least on Intel hardware, the texture size will be rounded up
to at least 1MB so we might as well try to aim for that as an
initial minimum size. If the format is only 1 byte per pixel we
can use 1024x1024, otherwise we'll assume it will take 4 bytes
per pixel and use 512x512. */
if (_cogl_get_format_bpp (format) == 1)
size = 1024;
else
size = 512;
/* Some platforms might not support this large size so we'll
decrease the size until it can */
while (size > 1 &&
!_cogl_texture_driver_size_supported (GL_TEXTURE_2D,
gl_intformat,
gl_type,
size, size))
size >>= 1;
*map_width = size;
*map_height = size;
}
static CoglRectangleMap *
_cogl_atlas_create_map (CoglPixelFormat format,
unsigned int map_width,
unsigned int map_height,
unsigned int n_textures,
CoglAtlasRepositionData *textures)
{
GLenum gl_intformat;
GLenum gl_type;
_cogl_pixel_format_to_gl (format,
&gl_intformat,
NULL, /* gl_format */
&gl_type);
/* Keep trying increasingly larger atlases until we can fit all of
the textures */
while (_cogl_texture_driver_size_supported (GL_TEXTURE_2D,
gl_intformat,
gl_type,
map_width, map_height))
{
CoglRectangleMap *new_atlas = _cogl_rectangle_map_new (map_width,
map_height,
NULL);
unsigned int i;
COGL_NOTE (ATLAS, "Trying to resize the atlas to %ux%u",
map_width, map_height);
/* Add all of the textures and keep track of the new position */
for (i = 0; i < n_textures; i++)
if (!_cogl_rectangle_map_add (new_atlas,
textures[i].old_position.width,
textures[i].old_position.height,
textures[i].user_data,
&textures[i].new_position))
break;
/* If the atlas can contain all of the textures then we have a
winner */
if (i >= n_textures)
return new_atlas;
else
COGL_NOTE (ATLAS, "Atlas size abandoned after trying "
"%u out of %u textures",
i, n_textures);
_cogl_rectangle_map_free (new_atlas);
_cogl_atlas_get_next_size (&map_width, &map_height);
}
/* If we get here then there's no atlas that can accommodate all of
the rectangles */
return NULL;
}
static CoglHandle
_cogl_atlas_create_texture (CoglAtlas *atlas,
int width,
int height)
{
CoglHandle tex;
if ((atlas->flags & COGL_ATLAS_CLEAR_TEXTURE))
{
guint8 *clear_data;
CoglBitmap *clear_bmp;
int bpp = _cogl_get_format_bpp (atlas->texture_format);
/* Create a buffer of zeroes to initially clear the texture */
clear_data = g_malloc0 (width * height * bpp);
clear_bmp = _cogl_bitmap_new_from_data (clear_data,
atlas->texture_format,
width,
height,
width * bpp,
(CoglBitmapDestroyNotify) g_free,
NULL);
tex = _cogl_texture_2d_new_from_bitmap (clear_bmp, COGL_TEXTURE_NONE,
atlas->texture_format);
cogl_object_unref (clear_bmp);
}
else
tex = _cogl_texture_2d_new_with_size (width, height, COGL_TEXTURE_NONE,
atlas->texture_format);
return tex;
}
static int
_cogl_atlas_compare_size_cb (const void *a,
const void *b)
{
const CoglAtlasRepositionData *ta = a;
const CoglAtlasRepositionData *tb = b;
unsigned int a_size, b_size;
a_size = ta->old_position.width * ta->old_position.height;
b_size = tb->old_position.width * tb->old_position.height;
return a_size < b_size ? 1 : a_size > b_size ? -1 : 0;
}
static void
_cogl_atlas_notify_reorganize (CoglAtlas *atlas)
{
_cogl_callback_list_invoke (&atlas->reorganize_callbacks);
}
gboolean
_cogl_atlas_reserve_space (CoglAtlas *atlas,
unsigned int width,
unsigned int height,
void *user_data)
{
CoglAtlasGetRectanglesData data;
CoglRectangleMap *new_map;
CoglHandle new_tex;
unsigned int map_width, map_height;
gboolean ret;
CoglRectangleMapEntry new_position;
/* Check if we can fit the rectangle into the existing map */
if (atlas->map &&
_cogl_rectangle_map_add (atlas->map, width, height,
user_data,
&new_position))
{
int waste =
_cogl_rectangle_map_get_remaining_space (atlas->map) *
100 / (_cogl_rectangle_map_get_width (atlas->map) *
_cogl_rectangle_map_get_height (atlas->map));
COGL_NOTE (ATLAS, "%p: Atlas is %ix%i, has %i textures and is %i%% waste",
atlas,
_cogl_rectangle_map_get_width (atlas->map),
_cogl_rectangle_map_get_height (atlas->map),
_cogl_rectangle_map_get_n_rectangles (atlas->map),
waste);
atlas->update_position_cb (user_data,
atlas->texture,
&new_position);
return TRUE;
}
/* We need to reorganise the atlas so we'll get an array of all the
textures currently in the atlas. */
data.n_textures = 0;
if (atlas->map == NULL)
data.textures = g_malloc (sizeof (CoglAtlasRepositionData));
else
{
unsigned int n_rectangles =
_cogl_rectangle_map_get_n_rectangles (atlas->map);
data.textures = g_malloc (sizeof (CoglAtlasRepositionData) *
(n_rectangles + 1));
_cogl_rectangle_map_foreach (atlas->map,
_cogl_atlas_get_rectangles_cb,
&data);
}
/* Add the new rectangle as a dummy texture so that it can be
positioned with the rest */
data.textures[data.n_textures].old_position.x = 0;
data.textures[data.n_textures].old_position.y = 0;
data.textures[data.n_textures].old_position.width = width;
data.textures[data.n_textures].old_position.height = height;
data.textures[data.n_textures++].user_data = user_data;
/* The atlasing algorithm works a lot better if the rectangles are
added in decreasing order of size so we'll first sort the
array */
qsort (data.textures, data.n_textures,
sizeof (CoglAtlasRepositionData),
_cogl_atlas_compare_size_cb);
/* Try to create a new atlas that can contain all of the textures */
if (atlas->map)
{
map_width = _cogl_rectangle_map_get_width (atlas->map);
map_height = _cogl_rectangle_map_get_height (atlas->map);
/* If there is enough space in for the new rectangle in the
existing atlas with at least 6% waste we'll start with the
same size, otherwise we'll immediately double it */
if ((map_width * map_height -
_cogl_rectangle_map_get_remaining_space (atlas->map) +
width * height) * 53 / 50 >
map_width * map_height)
_cogl_atlas_get_next_size (&map_width, &map_height);
}
else
_cogl_atlas_get_initial_size (atlas->texture_format,
&map_width, &map_height);
new_map = _cogl_atlas_create_map (atlas->texture_format,
map_width, map_height,
data.n_textures, data.textures);
/* If we can't create a map with the texture then give up */
if (new_map == NULL)
{
COGL_NOTE (ATLAS, "%p: Could not fit texture in the atlas", atlas);
ret = FALSE;
}
/* We need to migrate the existing textures into a new texture */
else if ((new_tex = _cogl_atlas_create_texture
(atlas,
_cogl_rectangle_map_get_width (new_map),
_cogl_rectangle_map_get_height (new_map))) == COGL_INVALID_HANDLE)
{
COGL_NOTE (ATLAS, "%p: Could not create a CoglTexture2D", atlas);
_cogl_rectangle_map_free (new_map);
ret = FALSE;
}
else
{
int waste;
_cogl_atlas_notify_reorganize (atlas);
COGL_NOTE (ATLAS,
"%p: Atlas %s with size %ix%i",
atlas,
atlas->map == NULL ||
_cogl_rectangle_map_get_width (atlas->map) !=
_cogl_rectangle_map_get_width (new_map) ||
_cogl_rectangle_map_get_height (atlas->map) !=
_cogl_rectangle_map_get_height (new_map) ?
"resized" : "reorganized",
_cogl_rectangle_map_get_width (new_map),
_cogl_rectangle_map_get_height (new_map));
if (atlas->map)
{
/* Move all the textures to the right position in the new
texture. This will also update the texture's rectangle */
_cogl_atlas_migrate (atlas,
data.n_textures,
data.textures,
atlas->texture,
new_tex,
user_data);
_cogl_rectangle_map_free (atlas->map);
cogl_handle_unref (atlas->texture);
}
else
/* We know there's only one texture so we can just directly
update the rectangle from its new position */
atlas->update_position_cb (data.textures[0].user_data,
new_tex,
&data.textures[0].new_position);
atlas->map = new_map;
atlas->texture = new_tex;
waste = (_cogl_rectangle_map_get_remaining_space (atlas->map) *
100 / (_cogl_rectangle_map_get_width (atlas->map) *
_cogl_rectangle_map_get_height (atlas->map)));
COGL_NOTE (ATLAS, "%p: Atlas is %ix%i, has %i textures and is %i%% waste",
atlas,
_cogl_rectangle_map_get_width (atlas->map),
_cogl_rectangle_map_get_height (atlas->map),
_cogl_rectangle_map_get_n_rectangles (atlas->map),
waste);
ret = TRUE;
}
g_free (data.textures);
return ret;
}
void
_cogl_atlas_remove (CoglAtlas *atlas,
const CoglRectangleMapEntry *rectangle)
{
_cogl_rectangle_map_remove (atlas->map, rectangle);
COGL_NOTE (ATLAS, "%p: Removed rectangle sized %ix%i",
atlas,
rectangle->width,
rectangle->height);
COGL_NOTE (ATLAS, "%p: Atlas is %ix%i, has %i textures and is %i%% waste",
atlas,
_cogl_rectangle_map_get_width (atlas->map),
_cogl_rectangle_map_get_height (atlas->map),
_cogl_rectangle_map_get_n_rectangles (atlas->map),
_cogl_rectangle_map_get_remaining_space (atlas->map) *
100 / (_cogl_rectangle_map_get_width (atlas->map) *
_cogl_rectangle_map_get_height (atlas->map)));
};
CoglHandle
_cogl_atlas_copy_rectangle (CoglAtlas *atlas,
unsigned int x,
unsigned int y,
unsigned int width,
unsigned int height,
CoglTextureFlags flags,
CoglPixelFormat format)
{
CoglHandle tex;
CoglAtlasBlitData blit_data;
/* Create a new texture at the right size */
tex = cogl_texture_new_with_size (width, height, flags, format);
/* Blit the data out of the atlas to the new texture. If FBOs
aren't available this will end up having to copy the entire
atlas texture */
_cogl_atlas_blit_begin (&blit_data, tex, atlas->texture);
_cogl_atlas_blit (&blit_data,
x, y,
0, 0,
width, height);
_cogl_atlas_blit_end (&blit_data);
return tex;
}
void
_cogl_atlas_add_reorganize_callback (CoglAtlas *atlas,
CoglCallbackListFunc callback,
void *user_data)
{
_cogl_callback_list_add (&atlas->reorganize_callbacks, callback, user_data);
}
void
_cogl_atlas_remove_reorganize_callback (CoglAtlas *atlas,
CoglCallbackListFunc callback,
void *user_data)
{
_cogl_callback_list_remove (&atlas->reorganize_callbacks,
callback, user_data);
}