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mutter-performance-source/clutter/cogl/gles/cogl-fbo.c
Havoc Pennington 08932584b5 Virtualize GL matrix operations and use a client-side matrix when GL is indirect
This is useful because sometimes we need to get the current matrix, which
is too expensive when indirect rendering.

In addition, this virtualization makes it easier to clean up the API in
the future.
2009-03-12 18:32:45 +00:00

354 lines
9.4 KiB
C

/*
* Clutter COGL
*
* A basic GL/GLES Abstraction/Utility Layer
*
* 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, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "cogl.h"
#include "cogl-internal.h"
#include "cogl-util.h"
#include "cogl-texture-private.h"
#include "cogl-fbo.h"
#include "cogl-context.h"
#include "cogl-handle.h"
#include "cogl-gles2-wrapper.h"
#ifdef HAVE_COGL_GLES2
static void _cogl_offscreen_free (CoglFbo *fbo);
COGL_HANDLE_DEFINE (Fbo, offscreen, fbo_handles);
CoglHandle
cogl_offscreen_new_to_texture (CoglHandle texhandle)
{
CoglTexture *tex;
CoglFbo *fbo;
CoglTexSliceSpan *x_span;
CoglTexSliceSpan *y_span;
GLuint tex_gl_handle;
GLuint fbo_gl_handle;
GLuint gl_stencil_handle;
GLenum status;
_COGL_GET_CONTEXT (ctx, COGL_INVALID_HANDLE);
if (!cogl_features_available (COGL_FEATURE_OFFSCREEN))
return COGL_INVALID_HANDLE;
/* Make texhandle is a valid texture object */
if (!cogl_is_texture (texhandle))
return COGL_INVALID_HANDLE;
tex = _cogl_texture_pointer_from_handle (texhandle);
/* The texture must not be sliced */
if (tex->slice_gl_handles == NULL)
return COGL_INVALID_HANDLE;
if (tex->slice_gl_handles->len != 1)
return COGL_INVALID_HANDLE;
/* Pick the single texture slice width, height and GL id */
x_span = &g_array_index (tex->slice_x_spans, CoglTexSliceSpan, 0);
y_span = &g_array_index (tex->slice_y_spans, CoglTexSliceSpan, 0);
tex_gl_handle = g_array_index (tex->slice_gl_handles, GLuint, 0);
/* Create a renderbuffer for stenciling */
GE( glGenRenderbuffers (1, &gl_stencil_handle) );
GE( glBindRenderbuffer (GL_RENDERBUFFER, gl_stencil_handle) );
GE( glRenderbufferStorage (GL_RENDERBUFFER, GL_STENCIL_INDEX8,
cogl_texture_get_width (texhandle),
cogl_texture_get_height (texhandle)) );
GE( glBindRenderbuffer (GL_RENDERBUFFER, 0) );
/* Generate framebuffer */
glGenFramebuffers (1, &fbo_gl_handle);
GE( glBindFramebuffer (GL_FRAMEBUFFER, fbo_gl_handle) );
GE( glFramebufferTexture2D (GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
tex->gl_target, tex_gl_handle, 0) );
GE( glFramebufferRenderbuffer (GL_FRAMEBUFFER,
GL_STENCIL_ATTACHMENT,
GL_RENDERBUFFER, gl_stencil_handle) );
/* Make sure it's complete */
status = glCheckFramebufferStatus (GL_FRAMEBUFFER);
if (status != GL_FRAMEBUFFER_COMPLETE)
{
/* Stencil renderbuffers aren't always supported. Try again
without the stencil buffer */
GE( glFramebufferRenderbuffer (GL_FRAMEBUFFER,
GL_STENCIL_ATTACHMENT,
GL_RENDERBUFFER,
0) );
GE( glDeleteRenderbuffers (1, &gl_stencil_handle) );
gl_stencil_handle = 0;
status = glCheckFramebufferStatus (GL_FRAMEBUFFER);
if (status != GL_FRAMEBUFFER_COMPLETE)
{
/* Still failing, so give up */
GE( glDeleteFramebuffers (1, &fbo_gl_handle) );
GE( glBindFramebuffer (GL_FRAMEBUFFER, 0) );
return COGL_INVALID_HANDLE;
}
}
GE( glBindFramebuffer (GL_FRAMEBUFFER, 0) );
/* Allocate and init a CoglFbo object (store non-wasted size
for subsequent blits and viewport setup) */
fbo = (CoglFbo*) g_malloc (sizeof (CoglFbo));
fbo->ref_count = 1;
fbo->width = x_span->size - x_span->waste;
fbo->height = y_span->size - y_span->waste;
fbo->gl_handle = fbo_gl_handle;
fbo->gl_stencil_handle = gl_stencil_handle;
COGL_HANDLE_DEBUG_NEW (offscreen, fbo);
return _cogl_offscreen_handle_new (fbo);
}
CoglHandle
cogl_offscreen_new_multisample ()
{
if (!cogl_features_available (COGL_FEATURE_OFFSCREEN_MULTISAMPLE))
return COGL_INVALID_HANDLE;
return COGL_INVALID_HANDLE;
}
static void
_cogl_offscreen_free (CoglFbo *fbo)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
/* Frees FBO resources but its handle is not
released! Do that separately before this! */
if (fbo->gl_stencil_handle)
GE( glDeleteRenderbuffers (1, &fbo->gl_stencil_handle) );
GE( glDeleteFramebuffers (1, &fbo->gl_handle) );
g_free (fbo);
}
void
cogl_offscreen_blit_region (CoglHandle src_buffer,
CoglHandle dst_buffer,
int src_x,
int src_y,
int src_w,
int src_h,
int dst_x,
int dst_y,
int dst_w,
int dst_h)
{
/* Not supported on GLES */
return;
}
void
cogl_offscreen_blit (CoglHandle src_buffer,
CoglHandle dst_buffer)
{
/* Not supported on GLES */
return;
}
void
cogl_draw_buffer (CoglBufferTarget target, CoglHandle offscreen)
{
CoglFbo *fbo = NULL;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (target == COGL_OFFSCREEN_BUFFER)
{
GLboolean scissor_enabled;
GLint scissor_box[4];
/* Make sure it is a valid fbo handle */
if (!cogl_is_offscreen (offscreen))
return;
fbo = _cogl_offscreen_pointer_from_handle (offscreen);
/* Check current draw buffer target */
if (ctx->draw_buffer != COGL_OFFSCREEN_BUFFER)
{
/* Push the viewport and matrix setup if redirecting
from a non-screen buffer */
GE( glGetIntegerv (GL_VIEWPORT, ctx->viewport_store) );
_cogl_set_current_matrix (COGL_MATRIX_PROJECTION);
_cogl_current_matrix_push ();
_cogl_current_matrix_identity ();
_cogl_set_current_matrix (COGL_MATRIX_MODELVIEW);
_cogl_current_matrix_push ();
_cogl_current_matrix_identity ();
}
else
{
/* Override viewport and matrix setup if redirecting
from another offscreen buffer */
_cogl_set_current_matrix (COGL_MATRIX_PROJECTION);
_cogl_current_matrix_identity ();
_cogl_set_current_matrix (COGL_MATRIX_MODELVIEW);
_cogl_current_matrix_identity ();
}
/* Setup new viewport and matrices */
GE( glViewport (0, 0, fbo->width, fbo->height) );
_cogl_current_matrix_translate (-1.0f, -1.0f, 0.0f);
_cogl_current_matrix_scale (2.0f / fbo->width, 2.0f / fbo->height, 1.0f);
/* Bind offscreen framebuffer object */
GE( glBindFramebuffer (GL_FRAMEBUFFER, fbo->gl_handle) );
GE( glColorMask (GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE) );
/* Some implementation require a clear before drawing
to an fbo. Luckily it is affected by scissor test. */
/* FIXME: test where exactly this is needed end whether
a glClear with 0 argument is enough */
scissor_enabled = glIsEnabled (GL_SCISSOR_TEST);
GE( glGetIntegerv (GL_SCISSOR_BOX, scissor_box) );
GE( glScissor (0, 0, 0, 0) );
GE( glEnable (GL_SCISSOR_TEST) );
GE( glClear (GL_COLOR_BUFFER_BIT) );
if (!scissor_enabled)
glDisable (GL_SCISSOR_TEST);
glScissor (scissor_box[0], scissor_box[1],
scissor_box[2], scissor_box[3]);
}
else if ((target & COGL_WINDOW_BUFFER) ||
(target & COGL_MASK_BUFFER))
{
/* Check current draw buffer target */
if (ctx->draw_buffer == COGL_OFFSCREEN_BUFFER)
{
/* Pop viewport and matrices if redirecting back
from an offscreen buffer */
GE( glViewport (ctx->viewport_store[0], ctx->viewport_store[1],
ctx->viewport_store[2], ctx->viewport_store[3]) );
_cogl_set_current_matrix (COGL_MATRIX_PROJECTION);
_cogl_current_matrix_pop ();
_cogl_set_current_matrix (COGL_MATRIX_MODELVIEW);
_cogl_current_matrix_pop ();
}
/* Bind window framebuffer object */
GE( glBindFramebuffer (GL_FRAMEBUFFER, 0) );
if (target == COGL_WINDOW_BUFFER)
{
/* Draw to RGB channels */
GE( glColorMask (GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE) );
}
else if (target == COGL_MASK_BUFFER)
{
/* Draw only to ALPHA channel */
GE( glColorMask (GL_FALSE, GL_FALSE, GL_FALSE, GL_TRUE) );
}
else
{
/* Draw to all channels */
GE( glColorMask (GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE) );
}
}
/* Store new target */
ctx->draw_buffer = target;
}
#else /* HAVE_COGL_GLES2 */
/* No support on regular OpenGL 1.1 */
gboolean
cogl_is_offscreen (CoglHandle handle)
{
return FALSE;
}
CoglHandle
cogl_offscreen_new_to_texture (CoglHandle texhandle)
{
return COGL_INVALID_HANDLE;
}
CoglHandle
cogl_offscreen_new_multisample ()
{
return COGL_INVALID_HANDLE;
}
CoglHandle
cogl_offscreen_ref (CoglHandle handle)
{
return COGL_INVALID_HANDLE;
}
void
cogl_offscreen_unref (CoglHandle handle)
{
}
void
cogl_offscreen_blit_region (CoglHandle src_buffer,
CoglHandle dst_buffer,
int src_x,
int src_y,
int src_w,
int src_h,
int dst_x,
int dst_y,
int dst_w,
int dst_h)
{
}
void
cogl_offscreen_blit (CoglHandle src_buffer,
CoglHandle dst_buffer)
{
}
void
cogl_draw_buffer (CoglBufferTarget target, CoglHandle offscreen)
{
}
#endif /* HAVE_COGL_GLES2 */