mutter/cogl/cogl-framebuffer-private.h
Neil Roberts 10a38bb14f Add a public cogl_framebuffer_read_pixels_into_bitmap
This adds a public function to read pixels from a framebuffer into a
CoglBitmap. This replaces the internal function
_cogl_read_pixels_with_rowstride because a CoglBitmap contains a
rowstride so it can be used for the same purpose. A CoglBitmap already
has public API to make one that points to a CoglPixelBuffer so this
function can be used to read pixels into a PBO. It also avoids the
need to push the framebuffer on to the context's stack so it provides
a function which can be used in the 2.0 API after the stack is
removed.

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2012-03-05 18:16:10 +00:00

393 lines
13 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2007,2008,2009 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, see <http://www.gnu.org/licenses/>.
*
*
*/
#ifndef __COGL_FRAMEBUFFER_PRIVATE_H
#define __COGL_FRAMEBUFFER_PRIVATE_H
#include "cogl-object-private.h"
#include "cogl-matrix-stack.h"
#include "cogl-clip-state-private.h"
#include "cogl-journal-private.h"
#include "cogl-winsys-private.h"
#include "cogl-attribute-private.h"
#include "cogl-offscreen.h"
#ifdef COGL_HAS_XLIB_SUPPORT
#include <X11/Xlib.h>
#endif
#ifdef COGL_HAS_GLX_SUPPORT
#include <GL/glx.h>
#include <GL/glxext.h>
#endif
typedef enum _CoglFramebufferType {
COGL_FRAMEBUFFER_TYPE_ONSCREEN,
COGL_FRAMEBUFFER_TYPE_OFFSCREEN
} CoglFramebufferType;
typedef struct
{
CoglSwapChain *swap_chain;
gboolean need_stencil;
int samples_per_pixel;
gboolean swap_throttled;
} CoglFramebufferConfig;
/* Flags to pass to _cogl_offscreen_new_to_texture_full */
typedef enum
{
COGL_OFFSCREEN_DISABLE_DEPTH_AND_STENCIL = 1
} CoglOffscreenFlags;
/* XXX: The order of these indices determines the order they are
* flushed.
*
* Flushing clip state may trash the modelview and projection matrices
* so we must do it before flushing the matrices.
*/
typedef enum _CoglFramebufferStateIndex
{
COGL_FRAMEBUFFER_STATE_INDEX_BIND = 0,
COGL_FRAMEBUFFER_STATE_INDEX_VIEWPORT = 1,
COGL_FRAMEBUFFER_STATE_INDEX_CLIP = 2,
COGL_FRAMEBUFFER_STATE_INDEX_DITHER = 3,
COGL_FRAMEBUFFER_STATE_INDEX_MODELVIEW = 4,
COGL_FRAMEBUFFER_STATE_INDEX_PROJECTION = 5,
COGL_FRAMEBUFFER_STATE_INDEX_COLOR_MASK = 6,
COGL_FRAMEBUFFER_STATE_INDEX_FRONT_FACE_WINDING = 7,
COGL_FRAMEBUFFER_STATE_INDEX_MAX = 8
} CoglFramebufferStateIndex;
typedef enum _CoglFramebufferState
{
COGL_FRAMEBUFFER_STATE_BIND = 1<<0,
COGL_FRAMEBUFFER_STATE_VIEWPORT = 1<<1,
COGL_FRAMEBUFFER_STATE_CLIP = 1<<2,
COGL_FRAMEBUFFER_STATE_DITHER = 1<<3,
COGL_FRAMEBUFFER_STATE_MODELVIEW = 1<<4,
COGL_FRAMEBUFFER_STATE_PROJECTION = 1<<5,
COGL_FRAMEBUFFER_STATE_COLOR_MASK = 1<<6,
COGL_FRAMEBUFFER_STATE_FRONT_FACE_WINDING = 1<<7
} CoglFramebufferState;
#define COGL_FRAMEBUFFER_STATE_ALL ((1<<COGL_FRAMEBUFFER_STATE_INDEX_MAX) - 1)
struct _CoglFramebuffer
{
CoglObject _parent;
CoglContext *context;
CoglFramebufferType type;
/* The user configuration before allocation... */
CoglFramebufferConfig config;
int width;
int height;
/* Format of the pixels in the framebuffer (including the expected
premult state) */
CoglPixelFormat format;
gboolean allocated;
CoglMatrixStack *modelview_stack;
CoglMatrixStack *projection_stack;
float viewport_x;
float viewport_y;
float viewport_width;
float viewport_height;
CoglClipState clip_state;
gboolean dirty_bitmasks;
int red_bits;
int blue_bits;
int green_bits;
int alpha_bits;
gboolean dither_enabled;
CoglColorMask color_mask;
int samples_per_pixel;
/* We journal the textured rectangles we want to submit to OpenGL so
* we have an oppertunity to batch them together into less draw
* calls. */
CoglJournal *journal;
/* The scene of a given framebuffer may depend on images in other
* framebuffers... */
GList *deps;
/* As part of an optimization for reading-back single pixels from a
* framebuffer in some simple cases where the geometry is still
* available in the journal we need to track the bounds of the last
* region cleared, its color and we need to track when something
* does in fact draw to that region so it is no longer clear.
*/
float clear_color_red;
float clear_color_green;
float clear_color_blue;
float clear_color_alpha;
int clear_clip_x0;
int clear_clip_y0;
int clear_clip_x1;
int clear_clip_y1;
gboolean clear_clip_dirty;
};
struct _CoglOffscreen
{
CoglFramebuffer _parent;
GLuint fbo_handle;
GSList *renderbuffers;
CoglTexture *texture;
int texture_level;
int texture_level_width;
int texture_level_height;
/* FIXME: _cogl_offscreen_new_to_texture_full should be made to use
* fb->config to configure if we want a depth or stencil buffer so
* we can get rid of these flags */
CoglOffscreenFlags create_flags;
};
void
_cogl_framebuffer_init (CoglFramebuffer *framebuffer,
CoglContext *ctx,
CoglFramebufferType type,
CoglPixelFormat format,
int width,
int height);
void _cogl_framebuffer_free (CoglFramebuffer *framebuffer);
const CoglWinsysVtable *
_cogl_framebuffer_get_winsys (CoglFramebuffer *framebuffer);
void
_cogl_framebuffer_clear_without_flush4f (CoglFramebuffer *framebuffer,
unsigned long buffers,
float red,
float green,
float blue,
float alpha);
void
_cogl_framebuffer_dirty (CoglFramebuffer *framebuffer);
CoglClipState *
_cogl_framebuffer_get_clip_state (CoglFramebuffer *framebuffer);
/*
* _cogl_framebuffer_get_clip_stack:
* @framebuffer: A #CoglFramebuffer
*
* Gets a pointer to the current clip stack. This can be used to later
* return to the same clip stack state with
* _cogl_framebuffer_set_clip_stack(). A reference is not taken on the
* stack so if you want to keep it you should call
* _cogl_clip_stack_ref().
*
* Return value: a pointer to the @framebuffer clip stack.
*/
CoglClipStack *
_cogl_framebuffer_get_clip_stack (CoglFramebuffer *framebuffer);
/*
* _cogl_framebuffer_set_clip_stack:
* @framebuffer: A #CoglFramebuffer
* @stack: a pointer to the replacement clip stack
*
* Replaces the @framebuffer clip stack with @stack.
*/
void
_cogl_framebuffer_set_clip_stack (CoglFramebuffer *framebuffer,
CoglClipStack *stack);
CoglMatrixStack *
_cogl_framebuffer_get_modelview_stack (CoglFramebuffer *framebuffer);
CoglMatrixStack *
_cogl_framebuffer_get_projection_stack (CoglFramebuffer *framebuffer);
void
_cogl_framebuffer_add_dependency (CoglFramebuffer *framebuffer,
CoglFramebuffer *dependency);
void
_cogl_framebuffer_remove_all_dependencies (CoglFramebuffer *framebuffer);
void
_cogl_framebuffer_flush_journal (CoglFramebuffer *framebuffer);
void
_cogl_framebuffer_flush_dependency_journals (CoglFramebuffer *framebuffer);
void
_cogl_framebuffer_flush_state (CoglFramebuffer *draw_buffer,
CoglFramebuffer *read_buffer,
CoglFramebufferState state);
CoglFramebuffer *
_cogl_get_read_framebuffer (void);
GSList *
_cogl_create_framebuffer_stack (void);
void
_cogl_free_framebuffer_stack (GSList *stack);
/*
* _cogl_offscreen_new_to_texture_full:
* @texture: A #CoglTexture pointer
* @create_flags: Flags specifying how to create the FBO
* @level: The mipmap level within the texture to target
*
* Creates a new offscreen buffer which will target the given
* texture. By default the buffer will have a depth and stencil
* buffer. This can be disabled by passing
* %COGL_OFFSCREEN_DISABLE_DEPTH_AND_STENCIL in @create_flags.
*
* Return value: the new CoglOffscreen object.
*/
CoglOffscreen *
_cogl_offscreen_new_to_texture_full (CoglTexture *texture,
CoglOffscreenFlags create_flags,
unsigned int level);
/*
* _cogl_push_framebuffers:
* @draw_buffer: A pointer to the buffer used for drawing
* @read_buffer: A pointer to the buffer used for reading back pixels
*
* Redirects drawing and reading to the specified framebuffers as in
* cogl_push_framebuffer() except that it allows the draw and read
* buffer to be different. The buffers are pushed as a pair so that
* they can later both be restored with a single call to
* cogl_pop_framebuffer().
*/
void
_cogl_push_framebuffers (CoglFramebuffer *draw_buffer,
CoglFramebuffer *read_buffer);
/*
* _cogl_blit_framebuffer:
* @src_x: Source x position
* @src_y: Source y position
* @dst_x: Destination x position
* @dst_y: Destination y position
* @width: Width of region to copy
* @height: Height of region to copy
*
* This blits a region of the color buffer of the current draw buffer
* to the current read buffer. The draw and read buffers can be set up
* using _cogl_push_framebuffers(). This function should only be
* called if the COGL_PRIVATE_FEATURE_OFFSCREEN_BLIT feature is
* advertised. The two buffers must both be offscreen and have the
* same format.
*
* Note that this function differs a lot from the glBlitFramebuffer
* function provided by the GL_EXT_framebuffer_blit extension. Notably
* it doesn't support having different sizes for the source and
* destination rectangle. This isn't supported by the corresponding
* GL_ANGLE_framebuffer_blit extension on GLES2.0 and it doesn't seem
* like a particularly useful feature. If the application wanted to
* scale the results it may make more sense to draw a primitive
* instead.
*
* We can only really support blitting between two offscreen buffers
* for this function on GLES2.0. This is because we effectively render
* upside down to offscreen buffers to maintain Cogl's representation
* of the texture coordinate system where 0,0 is the top left of the
* texture. If we were to blit from an offscreen to an onscreen buffer
* then we would need to mirror the blit along the x-axis but the GLES
* extension does not support this.
*
* The GL function is documented to be affected by the scissor. This
* function therefore ensure that an empty clip stack is flushed
* before performing the blit which means the scissor is effectively
* ignored.
*
* The function also doesn't support specifying the buffers to copy
* and instead only the color buffer is copied. When copying the depth
* or stencil buffers the extension on GLES2.0 only supports copying
* the full buffer which would be awkward to document with this
* API. If we wanted to support that feature it may be better to have
* a separate function to copy the entire buffer for a given mask.
*/
void
_cogl_blit_framebuffer (unsigned int src_x,
unsigned int src_y,
unsigned int dst_x,
unsigned int dst_y,
unsigned int width,
unsigned int height);
void
_cogl_framebuffer_push_projection (CoglFramebuffer *framebuffer);
void
_cogl_framebuffer_pop_projection (CoglFramebuffer *framebuffer);
void
_cogl_framebuffer_save_clip_stack (CoglFramebuffer *framebuffer);
void
_cogl_framebuffer_restore_clip_stack (CoglFramebuffer *framebuffer);
void
_cogl_framebuffer_unref (CoglFramebuffer *framebuffer);
void
_cogl_framebuffer_draw_primitive (CoglFramebuffer *framebuffer,
CoglPipeline *pipeline,
CoglPrimitive *primitive,
CoglDrawFlags flags);
/* This can be called directly by the CoglJournal to draw attributes
* skipping the implicit journal flush, the framebuffer flush and
* pipeline validation. */
void
_cogl_framebuffer_draw_attributes (CoglFramebuffer *framebuffer,
CoglPipeline *pipeline,
CoglVerticesMode mode,
int first_vertex,
int n_vertices,
CoglAttribute **attributes,
int n_attributes,
CoglDrawFlags flags);
void
_cogl_framebuffer_draw_indexed_attributes (CoglFramebuffer *framebuffer,
CoglPipeline *pipeline,
CoglVerticesMode mode,
int first_vertex,
int n_vertices,
CoglIndices *indices,
CoglAttribute **attributes,
int n_attributes,
CoglDrawFlags flags);
#endif /* __COGL_FRAMEBUFFER_PRIVATE_H */