mutter/cogl/driver/gles/cogl-fbo.c
Robert Bragg 0bce7eac53 Intial Re-layout of the Cogl source code and introduction of a Cogl Winsys
As part of an incremental process to have Cogl be a standalone project we
want to re-consider how we organise the Cogl source code.

Currently this is the structure I'm aiming for:
cogl/
    cogl/
	<put common source here>
	winsys/
	   cogl-glx.c
	   cogl-wgl.c
	driver/
	    gl/
	    gles/
	os/ ?
    utils/
	cogl-fixed
	cogl-matrix-stack?
        cogl-journal?
        cogl-primitives?
    pango/

The new winsys component is a starting point for migrating window system
code (i.e.  x11,glx,wgl,osx,egl etc) from Clutter to Cogl.

The utils/ and pango/ directories aren't added by this commit, but they are
noted because I plan to add them soon.

Overview of the planned structure:

* The winsys/ API is the API that binds OpenGL to a specific window system,
  be that X11 or win32 etc.  Example are glx, wgl and egl. Much of the logic
  under clutter/{glx,osx,win32 etc} should migrate here.

* Note there is also the idea of a winsys-base that may represent a window
  system for which there are multiple winsys APIs.  An example of this is
  x11, since glx and egl may both be used with x11.  (currently only Clutter
  has the idea of a winsys-base)

* The driver/ represents a specific varient of OpenGL. Currently we have "gl"
  representing OpenGL 1.4-2.1 (mostly fixed function) and "gles" representing
  GLES 1.1 (fixed funciton) and 2.0 (fully shader based)

* Everything under cogl/ should fundamentally be supporting access to the
  GPU.  Essentially Cogl's most basic requirement is to provide a nice GPU
  Graphics API and drawing a line between this and the utility functionality
  we add to support Clutter should help keep this lean and maintainable.

* Code under utils/ as suggested builds on cogl/ adding more convenient
  APIs or mechanism to optimize special cases. Broadly speaking you can
  compare cogl/ to OpenGL and utils/ to GLU.

* clutter/pango will be moved to clutter/cogl/pango

How some of the internal configure.ac/pkg-config terminology has changed:
backendextra -> CLUTTER_WINSYS_BASE # e.g. "x11"
backendextralib -> CLUTTER_WINSYS_BASE_LIB # e.g. "x11/libclutter-x11.la"
clutterbackend -> {CLUTTER,COGL}_WINSYS # e.g. "glx"
CLUTTER_FLAVOUR -> {CLUTTER,COGL}_WINSYS
clutterbackendlib -> CLUTTER_WINSYS_LIB
CLUTTER_COGL -> COGL_DRIVER # e.g. "gl"

Note: The CLUTTER_FLAVOUR and CLUTTER_COGL defines are kept for apps

As the first thing to take advantage of the new winsys component in Cogl;
cogl_get_proc_address() has been moved from cogl/{gl,gles}/cogl.c into
cogl/common/cogl.c and this common implementation first trys
_cogl_winsys_get_proc_address() but if that fails then it falls back to
gmodule.
2009-10-16 18:58:50 +01:00

344 lines
9.8 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2008,2009 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.
*/
#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);
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->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;
return _cogl_offscreen_handle_new (fbo);
}
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_set_draw_buffer (CoglBufferTarget target, CoglHandle offscreen)
{
CoglFbo *fbo = NULL;
CoglDrawBufferState *draw_buffer;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
g_assert (ctx->draw_buffer_stack != NULL);
draw_buffer = ctx->draw_buffer_stack->data;
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 (draw_buffer->target != COGL_OFFSCREEN_BUFFER)
{
/* Push the viewport and matrix setup if redirecting
from a non-screen buffer */
GE( glGetIntegerv (GL_VIEWPORT, ctx->drv.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)
{
/* Check current draw buffer target */
if (draw_buffer->target == COGL_OFFSCREEN_BUFFER)
{
/* Pop viewport and matrices if redirecting back
from an offscreen buffer */
GE( glViewport (ctx->drv.viewport_store[0],
ctx->drv.viewport_store[1],
ctx->drv.viewport_store[2],
ctx->drv.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) );
}
/* Store new target */
draw_buffer->target = target;
if (draw_buffer->offscreen != offscreen)
{
if (draw_buffer->offscreen != COGL_INVALID_HANDLE)
cogl_handle_unref (draw_buffer->offscreen);
if (offscreen != COGL_INVALID_HANDLE)
cogl_handle_ref (offscreen);
draw_buffer->offscreen = offscreen;
}
}
void
cogl_push_draw_buffer(void)
{
CoglDrawBufferState *old;
CoglDrawBufferState *draw_buffer;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
g_assert (ctx->draw_buffer_stack != NULL);
old = ctx->draw_buffer_stack->data;
draw_buffer = g_slice_new0 (CoglDrawBufferState);
*draw_buffer = *old;
ctx->draw_buffer_stack =
g_slist_prepend (ctx->draw_buffer_stack, draw_buffer);
}
void
cogl_pop_draw_buffer(void)
{
CoglDrawBufferState *to_pop;
CoglDrawBufferState *to_restore;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
g_assert (ctx->draw_buffer_stack != NULL);
if (ctx->draw_buffer_stack->next == NULL)
{
g_warning ("1 more cogl_pop_draw_buffer() than cogl_push_draw_buffer()");
return;
}
to_pop = ctx->draw_buffer_stack->data;
to_restore = ctx->draw_buffer_stack->next->data;
/* the logic in cogl_set_draw_buffer() only works if
* to_pop is still on top of the stack, because
* cogl_set_draw_buffer() needs to know the previous
* state.
*/
cogl_set_draw_buffer (to_restore->target, to_restore->offscreen);
/* cogl_set_draw_buffer() should have set top of stack
* to to_restore
*/
g_assert (to_restore->target == to_pop->target);
g_assert (to_restore->offscreen == to_pop->offscreen);
g_assert (ctx->draw_buffer_stack->data == to_pop);
ctx->draw_buffer_stack =
g_slist_remove_link (ctx->draw_buffer_stack,
ctx->draw_buffer_stack);
g_slice_free (CoglDrawBufferState, to_pop);
}
#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_ref (CoglHandle handle)
{
return COGL_INVALID_HANDLE;
}
void
cogl_offscreen_unref (CoglHandle handle)
{
}
void
cogl_set_draw_buffer (CoglBufferTarget target, CoglHandle offscreen)
{
}
#endif /* HAVE_COGL_GLES2 */