mutter/cogl/cogl-clip-stack.h

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/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2007,2008,2009,2010 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, see <http://www.gnu.org/licenses/>.
*
*
*/
#ifndef __COGL_CLIP_STACK_H
#define __COGL_CLIP_STACK_H
#include "cogl2-path.h"
#include "cogl-matrix.h"
#include "cogl-primitive.h"
/* The clip stack works like a GSList where only a pointer to the top
of the stack is stored. The empty clip stack is represented simply
by the NULL pointer. When an entry is added to or removed from the
stack the new top of the stack is returned. When an entry is pushed
a new clip stack entry is created which effectively takes ownership
of the reference on the old entry. Therefore unrefing the top entry
effectively loses ownership of all entries in the stack */
typedef struct _CoglClipStack CoglClipStack;
typedef struct _CoglClipStackRect CoglClipStackRect;
typedef struct _CoglClipStackWindowRect CoglClipStackWindowRect;
typedef struct _CoglClipStackPath CoglClipStackPath;
typedef struct _CoglClipStackPrimitive CoglClipStackPrimitive;
typedef enum
{
COGL_CLIP_STACK_RECT,
COGL_CLIP_STACK_WINDOW_RECT,
COGL_CLIP_STACK_PATH,
COGL_CLIP_STACK_PRIMITIVE
} CoglClipStackType;
/* A clip stack consists a list of entries. Each entry has a reference
* count and a link to its parent node. The child takes a reference on
* the parent and the CoglClipStack holds a reference to the top of
* the stack. There are no links back from the parent to the
* children. This allows stacks that have common ancestry to share the
* entries.
*
* For example, the following sequence of operations would generate
* the tree below:
*
* CoglClipStack *stack_a = NULL;
* stack_a = _cogl_clip_stack_push_rectangle (stack_a, ...);
* stack_a = _cogl_clip_stack_push_rectangle (stack_a, ...);
* stack_a = _cogl_clip_stack_push_from_path (stack_a, ...);
* CoglClipStack *stack_b = NULL;
* stack_b = cogl_clip_stack_push_window_rectangle (stack_b, ...);
*
* stack_a
* \ holds a ref to
* +-----------+
* | path node |
* |ref count 1|
* +-----------+
* \
* +-----------+ +-----------+
* both tops hold | rect node | | rect node |
* a ref to the |ref count 2|--|ref count 1|
* same rect node +-----------+ +-----------+
* /
* +-----------+
* | win. rect |
* |ref count 1|
* +-----------+
* / holds a ref to
* stack_b
*
*/
struct _CoglClipStack
{
CoglClipStackType type;
/* This will be null if there is no parent. If it is not null then
this node must be holding a reference to the parent */
CoglClipStack *parent;
/* All clip entries have a window-space bounding box which we can
use to calculate a scissor. The scissor limits the clip so that
we don't need to do a full stencil clear if the stencil buffer is
needed. This is stored in Cogl's coordinate space (ie, 0,0 is the
top left) */
int bounds_x0;
int bounds_y0;
int bounds_x1;
int bounds_y1;
unsigned int ref_count;
};
struct _CoglClipStackRect
{
CoglClipStack _parent_data;
/* The rectangle for this clip */
float x0;
float y0;
float x1;
float y1;
/* If this is true then the clip for this rectangle is entirely
described by the scissor bounds. This implies that the rectangle
is screen aligned and we don't need to use the stencil buffer to
set the clip. We keep the entry as a rect entry rather than a
window rect entry so that it will be easier to detect if the
modelview matrix is that same as when a rectangle is added to the
journal. In that case we can use the original clip coordinates
and modify the rectangle instead. */
gboolean can_be_scissor;
/* The matrix that was current when the clip was set */
CoglMatrix matrix;
};
struct _CoglClipStackWindowRect
{
CoglClipStack _parent_data;
/* The window rect clip doesn't need any specific data because it
just adds to the scissor clip */
};
struct _CoglClipStackPath
{
CoglClipStack _parent_data;
/* The matrix that was current when the clip was set */
CoglMatrix matrix;
CoglPath *path;
};
struct _CoglClipStackPrimitive
{
CoglClipStack _parent_data;
/* The matrix that was current when the clip was set */
CoglMatrix matrix;
CoglPrimitive *primitive;
float bounds_x1;
float bounds_y1;
float bounds_x2;
float bounds_y2;
};
CoglClipStack *
_cogl_clip_stack_push_window_rectangle (CoglClipStack *stack,
int x_offset,
int y_offset,
int width,
int height);
[draw-buffers] First pass at overhauling Cogl's framebuffer management Cogl's support for offscreen rendering was originally written just to support the clutter_texture_new_from_actor API and due to lack of documentation and several confusing - non orthogonal - side effects of using the API it wasn't really possible to use directly. This commit does a number of things: - It removes {gl,gles}/cogl-fbo.{c,h} and adds shared cogl-draw-buffer.{c,h} files instead which should be easier to maintain. - internally CoglFbo objects are now called CoglDrawBuffers. A CoglDrawBuffer is an abstract base class that is inherited from to implement CoglOnscreen and CoglOffscreen draw buffers. CoglOffscreen draw buffers will initially be used to support the cogl_offscreen_new_to_texture API, and CoglOnscreen draw buffers will start to be used internally to represent windows as we aim to migrate some of Clutter's backend code to Cogl. - It makes draw buffer objects the owners of the following state: - viewport - projection matrix stack - modelview matrix stack - clip state (This means when you switch between draw buffers you will automatically be switching to their associated viewport, matrix and clip state) Aside from hopefully making cogl_offscreen_new_to_texture be more useful short term by having simpler and well defined semantics for cogl_set_draw_buffer, as mentioned above this is the first step for a couple of other things: - Its a step toward moving ownership for windows down from Clutter backends into Cogl, by (internally at least) introducing the CoglOnscreen draw buffer. Note: the plan is that cogl_set_draw_buffer will accept on or offscreen draw buffer handles, and the "target" argument will become redundant since we will instead query the type of the given draw buffer handle. - Because we have a common type for on and offscreen framebuffers we can provide a unified API for framebuffer management. Things like: - blitting between buffers - managing ancillary buffers (e.g. attaching depth and stencil buffers) - size requisition - clearing
2009-09-25 13:34:34 +00:00
CoglClipStack *
_cogl_clip_stack_push_rectangle (CoglClipStack *stack,
float x_1,
float y_1,
float x_2,
float y_2,
const CoglMatrix *modelview_matrix);
cogl: improves header and coding style consistency We've had complaints that our Cogl code/headers are a bit "special" so this is a first pass at tidying things up by giving them some consistency. These changes are all consistent with how new code in Cogl is being written, but the style isn't consistently applied across all code yet. There are two parts to this patch; but since each one required a large amount of effort to maintain tidy indenting it made sense to combine the changes to reduce the time spent re indenting the same lines. The first change is to use a consistent style for declaring function prototypes in headers. Cogl headers now consistently use this style for prototypes: return_type cogl_function_name (CoglType arg0, CoglType arg1); Not everyone likes this style, but it seems that most of the currently active Cogl developers agree on it. The second change is to constrain the use of redundant glib data types in Cogl. Uses of gint, guint, gfloat, glong, gulong and gchar have all been replaced with int, unsigned int, float, long, unsigned long and char respectively. When talking about pixel data; use of guchar has been replaced with guint8, otherwise unsigned char can be used. The glib types that we continue to use for portability are gboolean, gint{8,16,32,64}, guint{8,16,32,64} and gsize. The general intention is that Cogl should look palatable to the widest range of C programmers including those outside the Gnome community so - especially for the public API - we want to minimize the number of foreign looking typedefs.
2010-02-10 01:57:32 +00:00
CoglClipStack *
_cogl_clip_stack_push_from_path (CoglClipStack *stack,
CoglPath *path,
const CoglMatrix *modelview_matrix);
CoglClipStack *
_cogl_clip_stack_push_primitive (CoglClipStack *stack,
CoglPrimitive *primitive,
float bounds_x1,
float bounds_y1,
float bounds_x2,
float bounds_y2,
const CoglMatrix *modelview_matrix);
CoglClipStack *
_cogl_clip_stack_pop (CoglClipStack *stack);
cogl: improves header and coding style consistency We've had complaints that our Cogl code/headers are a bit "special" so this is a first pass at tidying things up by giving them some consistency. These changes are all consistent with how new code in Cogl is being written, but the style isn't consistently applied across all code yet. There are two parts to this patch; but since each one required a large amount of effort to maintain tidy indenting it made sense to combine the changes to reduce the time spent re indenting the same lines. The first change is to use a consistent style for declaring function prototypes in headers. Cogl headers now consistently use this style for prototypes: return_type cogl_function_name (CoglType arg0, CoglType arg1); Not everyone likes this style, but it seems that most of the currently active Cogl developers agree on it. The second change is to constrain the use of redundant glib data types in Cogl. Uses of gint, guint, gfloat, glong, gulong and gchar have all been replaced with int, unsigned int, float, long, unsigned long and char respectively. When talking about pixel data; use of guchar has been replaced with guint8, otherwise unsigned char can be used. The glib types that we continue to use for portability are gboolean, gint{8,16,32,64}, guint{8,16,32,64} and gsize. The general intention is that Cogl should look palatable to the widest range of C programmers including those outside the Gnome community so - especially for the public API - we want to minimize the number of foreign looking typedefs.
2010-02-10 01:57:32 +00:00
void
_cogl_clip_stack_get_bounds (CoglClipStack *stack,
int *scissor_x0,
int *scissor_y0,
int *scissor_x1,
int *scissor_y1);
cogl: improves header and coding style consistency We've had complaints that our Cogl code/headers are a bit "special" so this is a first pass at tidying things up by giving them some consistency. These changes are all consistent with how new code in Cogl is being written, but the style isn't consistently applied across all code yet. There are two parts to this patch; but since each one required a large amount of effort to maintain tidy indenting it made sense to combine the changes to reduce the time spent re indenting the same lines. The first change is to use a consistent style for declaring function prototypes in headers. Cogl headers now consistently use this style for prototypes: return_type cogl_function_name (CoglType arg0, CoglType arg1); Not everyone likes this style, but it seems that most of the currently active Cogl developers agree on it. The second change is to constrain the use of redundant glib data types in Cogl. Uses of gint, guint, gfloat, glong, gulong and gchar have all been replaced with int, unsigned int, float, long, unsigned long and char respectively. When talking about pixel data; use of guchar has been replaced with guint8, otherwise unsigned char can be used. The glib types that we continue to use for portability are gboolean, gint{8,16,32,64}, guint{8,16,32,64} and gsize. The general intention is that Cogl should look palatable to the widest range of C programmers including those outside the Gnome community so - especially for the public API - we want to minimize the number of foreign looking typedefs.
2010-02-10 01:57:32 +00:00
void
_cogl_clip_stack_flush (CoglClipStack *stack,
CoglFramebuffer *framebuffer);
CoglClipStack *
_cogl_clip_stack_ref (CoglClipStack *stack);
void
_cogl_clip_stack_unref (CoglClipStack *stack);
#endif /* __COGL_CLIP_STACK_H */