mutter/cogl/cogl-blit.c
Neil Roberts 2059ae3ac8 Add internal _cogl_push_source to optionally disable legacy state
Some code in Cogl such as when flushing a stencil clip assumes that it
can push a temporary simple pipeline to reset to a known state for
internal drawing operations. However this breaks down if the
application has set any legacy state because that is set globally so
it will also get applied to the internal pipeline.

_cogl_draw_attributes already had an internal flag to disable applying
the legacy state but I think this is quite awkward to use because not
all places that push a pipeline draw the attribute buffers directly so
it is difficult to pass the flag down through the layers.

Conceptually the legacy state is meant to be like a layer on top of
the purely pipeline-based state API so I think ideally we should have
an internal function to push the source without the applying the
legacy state. The legacy state can't be applied as the pipeline is
pushed because the global state can be modified even after it is
pushed. This patch adds a _cogl_push_source() function which takes an
extra boolean flag to mark whether to enable the legacy state. The
value of this flag is stored alongside the pipeline in the pipeline
stack. Another new internal function called
_cogl_get_enable_legacy_state queries whether the top entry in the
pipeline stack has legacy state enabled. cogl-primitives and the
vertex array drawing code now use this to determine whether to apply
the legacy state when drawing. The COGL_DRAW_SKIP_LEGACY_STATE flag is
now removed.

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2011-09-19 16:40:06 +01:00

397 lines
12 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2011 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 <string.h>
#include "cogl.h"
#include "cogl-blit.h"
#include "cogl-context-private.h"
#include "cogl-framebuffer-private.h"
#include "cogl-texture-2d-private.h"
#include "cogl-private.h"
static const CoglBlitMode *_cogl_blit_default_mode = NULL;
static gboolean
_cogl_blit_texture_render_begin (CoglBlitData *data)
{
CoglHandle fbo;
CoglPipeline *pipeline;
unsigned int dst_width, dst_height;
_COGL_GET_CONTEXT (ctx, FALSE);
fbo = _cogl_offscreen_new_to_texture_full
(data->dst_tex, COGL_OFFSCREEN_DISABLE_DEPTH_AND_STENCIL, 0 /* level */);
if (fbo == COGL_INVALID_HANDLE)
return FALSE;
cogl_push_framebuffer (fbo);
cogl_handle_unref (fbo);
dst_width = cogl_texture_get_width (data->dst_tex);
dst_height = cogl_texture_get_height (data->dst_tex);
/* Set up an orthographic projection so we can use pixel
coordinates to render to the texture */
cogl_ortho (0, /* left */
dst_width, /* right */
dst_height, /* bottom */
0, /* top */
-1, /* near */
1 /* far */);
/* We cache a pipeline used for migrating on to the context so
that it doesn't have to continuously regenerate a shader
program */
if (ctx->blit_texture_pipeline == NULL)
{
ctx->blit_texture_pipeline = cogl_pipeline_new ();
cogl_pipeline_set_layer_filters (ctx->blit_texture_pipeline, 0,
COGL_PIPELINE_FILTER_NEAREST,
COGL_PIPELINE_FILTER_NEAREST);
/* Disable blending by just directly taking the contents of the
source texture */
cogl_pipeline_set_blend (ctx->blit_texture_pipeline,
"RGBA = ADD(SRC_COLOR, 0)",
NULL);
}
pipeline = ctx->blit_texture_pipeline;
cogl_pipeline_set_layer_texture (pipeline, 0, data->src_tex);
_cogl_push_source (pipeline, FALSE);
return TRUE;
}
static void
_cogl_blit_texture_render_blit (CoglBlitData *data,
unsigned int src_x,
unsigned int src_y,
unsigned int dst_x,
unsigned int dst_y,
unsigned int width,
unsigned int height)
{
cogl_rectangle_with_texture_coords (dst_x, dst_y,
dst_x + width,
dst_y + height,
src_x / (float) data->src_width,
src_y / (float) data->src_height,
(src_x + width) /
(float) data->src_width,
(src_y + height) /
(float) data->src_height);
}
static void
_cogl_blit_texture_render_end (CoglBlitData *data)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
cogl_pop_source ();
cogl_pop_framebuffer ();
/* Attach the target texture to the texture render pipeline so that
we don't keep a reference to the source texture forever. This is
assuming that the destination texture will live for a long time
which is currently the case when cogl_blit_* is used from the
atlas code. It may be better in future to keep around a set of
dummy 1x1 textures for each texture target that we could bind
instead. This would also be useful when using a pipeline as a
hash table key such as for the ARBfp program cache. */
cogl_pipeline_set_layer_texture (ctx->blit_texture_pipeline, 0,
data->dst_tex);
}
static gboolean
_cogl_blit_framebuffer_begin (CoglBlitData *data)
{
CoglHandle dst_fbo, src_fbo;
_COGL_GET_CONTEXT (ctx, FALSE);
/* We can only blit between FBOs if both textures are the same
format and the blit framebuffer extension is supported */
if ((cogl_texture_get_format (data->src_tex) & ~COGL_A_BIT) !=
(cogl_texture_get_format (data->dst_tex) & ~COGL_A_BIT) ||
!cogl_features_available (COGL_FEATURE_OFFSCREEN_BLIT))
return FALSE;
dst_fbo = _cogl_offscreen_new_to_texture_full
(data->dst_tex, COGL_OFFSCREEN_DISABLE_DEPTH_AND_STENCIL, 0 /* level */);
if (dst_fbo == COGL_INVALID_HANDLE)
return FALSE;
src_fbo = _cogl_offscreen_new_to_texture_full
(data->src_tex, COGL_OFFSCREEN_DISABLE_DEPTH_AND_STENCIL, 0 /* level */);
if (src_fbo == COGL_INVALID_HANDLE)
{
cogl_handle_unref (dst_fbo);
return FALSE;
}
_cogl_push_framebuffers (dst_fbo, src_fbo);
cogl_handle_unref (src_fbo);
cogl_handle_unref (dst_fbo);
return TRUE;
}
static void
_cogl_blit_framebuffer_blit (CoglBlitData *data,
unsigned int src_x,
unsigned int src_y,
unsigned int dst_x,
unsigned int dst_y,
unsigned int width,
unsigned int height)
{
_cogl_blit_framebuffer (src_x, src_y,
dst_x, dst_y,
width, height);
}
static void
_cogl_blit_framebuffer_end (CoglBlitData *data)
{
cogl_pop_framebuffer ();
}
static gboolean
_cogl_blit_copy_tex_sub_image_begin (CoglBlitData *data)
{
CoglHandle fbo;
_COGL_GET_CONTEXT (ctx, FALSE);
/* This will only work if the target texture is a CoglTexture2D */
if (!cogl_is_texture_2d (data->dst_tex))
return FALSE;
fbo = _cogl_offscreen_new_to_texture_full
(data->src_tex, COGL_OFFSCREEN_DISABLE_DEPTH_AND_STENCIL, 0 /* level */);
if (fbo == COGL_INVALID_HANDLE)
return FALSE;
cogl_push_framebuffer (fbo);
cogl_handle_unref (fbo);
return TRUE;
}
static void
_cogl_blit_copy_tex_sub_image_blit (CoglBlitData *data,
unsigned int src_x,
unsigned int src_y,
unsigned int dst_x,
unsigned int dst_y,
unsigned int width,
unsigned int height)
{
_cogl_texture_2d_copy_from_framebuffer (data->dst_tex,
dst_x, dst_y,
src_x, src_y,
width, height);
}
static void
_cogl_blit_copy_tex_sub_image_end (CoglBlitData *data)
{
cogl_pop_framebuffer ();
}
static gboolean
_cogl_blit_get_tex_data_begin (CoglBlitData *data)
{
data->format = cogl_texture_get_format (data->src_tex);
data->bpp = _cogl_get_format_bpp (data->format);
data->image_data = g_malloc (data->bpp * data->src_width *
data->src_height);
cogl_texture_get_data (data->src_tex, data->format,
data->src_width * data->bpp, data->image_data);
return TRUE;
}
static void
_cogl_blit_get_tex_data_blit (CoglBlitData *data,
unsigned int src_x,
unsigned int src_y,
unsigned int dst_x,
unsigned int dst_y,
unsigned int width,
unsigned int height)
{
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_blit_get_tex_data_end (CoglBlitData *data)
{
g_free (data->image_data);
}
/* These should be specified in order of preference */
static const CoglBlitMode
_cogl_blit_modes[] =
{
{
"texture-render",
_cogl_blit_texture_render_begin,
_cogl_blit_texture_render_blit,
_cogl_blit_texture_render_end
},
{
"framebuffer",
_cogl_blit_framebuffer_begin,
_cogl_blit_framebuffer_blit,
_cogl_blit_framebuffer_end
},
{
"copy-tex-sub-image",
_cogl_blit_copy_tex_sub_image_begin,
_cogl_blit_copy_tex_sub_image_blit,
_cogl_blit_copy_tex_sub_image_end
},
{
"get-tex-data",
_cogl_blit_get_tex_data_begin,
_cogl_blit_get_tex_data_blit,
_cogl_blit_get_tex_data_end
}
};
void
_cogl_blit_begin (CoglBlitData *data,
CoglHandle dst_tex,
CoglHandle src_tex)
{
int i;
if (_cogl_blit_default_mode == NULL)
{
const char *default_mode_string;
/* Allow the default to be specified with an environment
variable. For the time being these functions are only used
when blitting between atlas textures so the environment
variable is named to be specific to the atlas code. If we
want to use the code in other places we should create another
environment variable for each specific use case */
if ((default_mode_string = g_getenv ("COGL_ATLAS_DEFAULT_BLIT_MODE")))
{
for (i = 0; i < G_N_ELEMENTS (_cogl_blit_modes); i++)
if (!strcmp (_cogl_blit_modes[i].name, default_mode_string))
{
_cogl_blit_default_mode = _cogl_blit_modes + i;
break;
}
if (i >= G_N_ELEMENTS (_cogl_blit_modes))
{
g_warning ("Unknown blit mode %s", default_mode_string);
_cogl_blit_default_mode = _cogl_blit_modes;
}
}
else
/* Default to the first blit mode */
_cogl_blit_default_mode = _cogl_blit_modes;
}
data->dst_tex = dst_tex;
data->src_tex = src_tex;
data->src_width = cogl_texture_get_width (src_tex);
data->src_height = cogl_texture_get_height (src_tex);
/* Try the default blit mode first */
if (!_cogl_blit_default_mode->begin_func (data))
{
COGL_NOTE (ATLAS, "Failed to set up blit mode %s",
_cogl_blit_default_mode->name);
/* Try all of the other modes in order */
for (i = 0; i < G_N_ELEMENTS (_cogl_blit_modes); i++)
if (_cogl_blit_modes + i != _cogl_blit_default_mode &&
_cogl_blit_modes[i].begin_func (data))
{
/* Use this mode as the default from now on */
_cogl_blit_default_mode = _cogl_blit_modes + i;
break;
}
else
COGL_NOTE (ATLAS,
"Failed to set up blit mode %s",
_cogl_blit_modes[i].name);
/* The last blit mode can't fail so this should never happen */
g_return_if_fail (i < G_N_ELEMENTS (_cogl_blit_modes));
}
data->blit_mode = _cogl_blit_default_mode;
COGL_NOTE (ATLAS, "Setup blit using %s", _cogl_blit_default_mode->name);
}
void
_cogl_blit (CoglBlitData *data,
unsigned int src_x,
unsigned int src_y,
unsigned int dst_x,
unsigned int dst_y,
unsigned int width,
unsigned int height)
{
data->blit_mode->blit_func (data, src_x, src_y, dst_x, dst_y, width, height);
}
void
_cogl_blit_end (CoglBlitData *data)
{
data->blit_mode->end_func (data);
}