mutter/cogl/cogl1-context.h
Robert Bragg ee940a3d0d Move all types/prototypes from cogl.h -> cogl[1]-context.h
So we can get to the point where cogl.h is merely an aggregation of
header includes for the 1.x api this moves all the function prototypes
and type definitions into a cogl-context.h and a new cogl1-context.h.

Ideally no code internally should ever need to include cogl.h as it just
represents the public facing header for accessing the 1.x api which
should only be used by Clutter.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2012-02-20 23:12:44 +00:00

1168 lines
36 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 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/>.
*
* Authors:
* Robert Bragg <robert@linux.intel.com>
*
*/
#if !defined(__COGL_H_INSIDE__) && !defined(CLUTTER_COMPILATION)
#error "Only <cogl/cogl.h> can be included directly."
#endif
#ifndef __COGL_1_CONTEXT_H__
#define __COGL_1_CONTEXT_H__
#include <glib.h>
#include <cogl/cogl-types.h>
#include <cogl/cogl-texture.h>
#include <cogl/cogl-framebuffer.h>
G_BEGIN_DECLS
/**
* cogl_get_option_group:
*
* Retrieves the #GOptionGroup used by Cogl to parse the command
* line options. Clutter uses this to handle the Cogl command line
* options during its initialization process.
*
* Return value: a #GOptionGroup
*
* Since: 1.0
*/
GOptionGroup *
cogl_get_option_group (void);
/* Misc */
/**
* cogl_get_features:
*
* Returns all of the features supported by COGL.
*
* Return value: A logical OR of all the supported COGL features.
*
* Since: 0.8
*/
CoglFeatureFlags
cogl_get_features (void);
/**
* cogl_features_available:
* @features: A bitmask of features to check for
*
* Checks whether the given COGL features are available. Multiple
* features can be checked for by or-ing them together with the '|'
* operator. %TRUE is only returned if all of the requested features
* are available.
*
* Return value: %TRUE if the features are available, %FALSE otherwise.
*/
gboolean
cogl_features_available (CoglFeatureFlags features);
/**
* cogl_get_proc_address:
* @name: the name of the function.
*
* Gets a pointer to a given GL or GL ES extension function. This acts
* as a wrapper around glXGetProcAddress() or whatever is the
* appropriate function for the current backend.
*
* Return value: a pointer to the requested function or %NULL if the
* function is not available.
*/
CoglFuncPtr
cogl_get_proc_address (const char *name);
#ifndef COGL_DISABLE_DEPRECATED
/**
* cogl_check_extension:
* @name: extension to check for
* @ext: list of extensions
*
* Check whether @name occurs in list of extensions in @ext.
*
* Return value: %TRUE if the extension occurs in the list, %FALSE otherwise.
*
* Deprecated: 1.2: OpenGL is an implementation detail for Cogl and so it's
* not appropriate to expose OpenGL extensions through the Cogl API. This
* function can be replaced by the following equivalent code:
* |[
* gboolean retval = (strstr (ext, name) != NULL) ? TRUE : FALSE;
* ]|
*/
gboolean
cogl_check_extension (const char *name,
const char *ext) G_GNUC_DEPRECATED;
#endif /* COGL_DISABLE_DEPRECATED */
/**
* cogl_get_bitmasks:
* @red: (out): Return location for the number of red bits or %NULL
* @green: (out): Return location for the number of green bits or %NULL
* @blue: (out): Return location for the number of blue bits or %NULL
* @alpha: (out): Return location for the number of alpha bits or %NULL
*
* Gets the number of bitplanes used for each of the color components
* in the color buffer. Pass %NULL for any of the arguments if the
* value is not required.
*/
void
cogl_get_bitmasks (int *red,
int *green,
int *blue,
int *alpha);
/**
* cogl_perspective:
* @fovy: Vertical field of view angle in degrees.
* @aspect: The (width over height) aspect ratio for display
* @z_near: The distance to the near clipping plane (Must be positive)
* @z_far: The distance to the far clipping plane (Must be positive)
*
* Replaces the current projection matrix with a perspective matrix
* based on the provided values.
*
* <note>You should be careful not to have to great a @z_far / @z_near
* ratio since that will reduce the effectiveness of depth testing
* since there wont be enough precision to identify the depth of
* objects near to each other.</note>
*/
void
cogl_perspective (float fovy,
float aspect,
float z_near,
float z_far);
/**
* cogl_frustum:
* @left: X position of the left clipping plane where it
* intersects the near clipping plane
* @right: X position of the right clipping plane where it
* intersects the near clipping plane
* @bottom: Y position of the bottom clipping plane where it
* intersects the near clipping plane
* @top: Y position of the top clipping plane where it intersects
* the near clipping plane
* @z_near: The distance to the near clipping plane (Must be positive)
* @z_far: The distance to the far clipping plane (Must be positive)
*
* Replaces the current projection matrix with a perspective matrix
* for a given viewing frustum defined by 4 side clip planes that
* all cross through the origin and 2 near and far clip planes.
*
* Since: 0.8.2
*/
void
cogl_frustum (float left,
float right,
float bottom,
float top,
float z_near,
float z_far);
/**
* cogl_ortho:
* @left: The coordinate for the left clipping plane
* @right: The coordinate for the right clipping plane
* @bottom: The coordinate for the bottom clipping plane
* @top: The coordinate for the top clipping plane
* @near: The <emphasis>distance</emphasis> to the near clipping
* plane (negative if the plane is behind the viewer)
* @far: The <emphasis>distance</emphasis> for the far clipping
* plane (negative if the plane is behind the viewer)
*
* Replaces the current projection matrix with an orthographic projection
* matrix. See <xref linkend="cogl-ortho-matrix"/> to see how the matrix is
* calculated.
*
* <figure id="cogl-ortho-matrix">
* <title></title>
* <graphic fileref="cogl_ortho.png" format="PNG"/>
* </figure>
*
* <note>This function copies the arguments from OpenGL's glOrtho() even
* though they are unnecessarily confusing due to the z near and z far
* arguments actually being a "distance" from the origin, where
* negative values are behind the viewer, instead of coordinates for
* the z clipping planes which would have been consistent with the
* left, right bottom and top arguments.</note>
*
* Since: 1.0
*/
void
cogl_ortho (float left,
float right,
float bottom,
float top,
float near,
float far);
#ifndef COGL_DISABLE_DEPRECATED
/**
* cogl_viewport:
* @width: Width of the viewport
* @height: Height of the viewport
*
* Replace the current viewport with the given values.
*
* Since: 0.8.2
*
* Deprecated: 1.2: Use cogl_set_viewport() instead
*/
void
cogl_viewport (unsigned int width,
unsigned int height) G_GNUC_DEPRECATED;
#endif /* COGL_DISABLE_DEPRECATED */
/**
* cogl_set_viewport:
* @x: X offset of the viewport
* @y: Y offset of the viewport
* @width: Width of the viewport
* @height: Height of the viewport
*
* Replaces the current viewport with the given values.
*
* Since: 1.2
*/
void
cogl_set_viewport (int x,
int y,
int width,
int height);
/**
* cogl_push_matrix:
*
* Stores the current model-view matrix on the matrix stack. The matrix
* can later be restored with cogl_pop_matrix().
*/
void
cogl_push_matrix (void);
/**
* cogl_pop_matrix:
*
* Restores the current model-view matrix from the matrix stack.
*/
void
cogl_pop_matrix (void);
/**
* cogl_scale:
* @x: Amount to scale along the x-axis
* @y: Amount to scale along the y-axis
* @z: Amount to scale along the z-axis
*
* Multiplies the current model-view matrix by one that scales the x,
* y and z axes by the given values.
*/
void
cogl_scale (float x,
float y,
float z);
/**
* cogl_translate:
* @x: Distance to translate along the x-axis
* @y: Distance to translate along the y-axis
* @z: Distance to translate along the z-axis
*
* Multiplies the current model-view matrix by one that translates the
* model along all three axes according to the given values.
*/
void
cogl_translate (float x,
float y,
float z);
/**
* cogl_rotate:
* @angle: Angle in degrees to rotate.
* @x: X-component of vertex to rotate around.
* @y: Y-component of vertex to rotate around.
* @z: Z-component of vertex to rotate around.
*
* Multiplies the current model-view matrix by one that rotates the
* model around the vertex specified by @x, @y and @z. The rotation
* follows the right-hand thumb rule so for example rotating by 10
* degrees about the vertex (0, 0, 1) causes a small counter-clockwise
* rotation.
*/
void
cogl_rotate (float angle,
float x,
float y,
float z);
/**
* cogl_transform:
* @matrix: the matrix to multiply with the current model-view
*
* Multiplies the current model-view matrix by the given matrix.
*
* Since: 1.4
*/
void
cogl_transform (const CoglMatrix *matrix);
/**
* cogl_get_modelview_matrix:
* @matrix: (out): return location for the model-view matrix
*
* Stores the current model-view matrix in @matrix.
*/
void
cogl_get_modelview_matrix (CoglMatrix *matrix);
/**
* cogl_set_modelview_matrix:
* @matrix: the new model-view matrix
*
* Loads @matrix as the new model-view matrix.
*/
void
cogl_set_modelview_matrix (CoglMatrix *matrix);
/**
* cogl_get_projection_matrix:
* @matrix: (out): return location for the projection matrix
*
* Stores the current projection matrix in @matrix.
*/
void
cogl_get_projection_matrix (CoglMatrix *matrix);
/**
* cogl_set_projection_matrix:
* @matrix: the new projection matrix
*
* Loads matrix as the new projection matrix.
*/
void
cogl_set_projection_matrix (CoglMatrix *matrix);
/**
* cogl_get_viewport:
* @v: (out) (array fixed-size=4): pointer to a 4 element array
* of #float<!-- -->s to receive the viewport dimensions.
*
* Stores the current viewport in @v. @v[0] and @v[1] get the x and y
* position of the viewport and @v[2] and @v[3] get the width and
* height.
*/
void
cogl_get_viewport (float v[4]);
/**
* cogl_set_depth_test_enabled:
* @setting: %TRUE to enable depth testing or %FALSE to disable.
*
* Sets whether depth testing is enabled. If it is disabled then the
* order that actors are layered on the screen depends solely on the
* order specified using clutter_actor_raise() and
* clutter_actor_lower(), otherwise it will also take into account the
* actor's depth. Depth testing is disabled by default.
*
* Deprecated: 1.4: Use cogl_material_set_depth_test_enabled()
* instead.
*/
void
cogl_set_depth_test_enabled (gboolean setting);
/**
* cogl_get_depth_test_enabled:
*
* Queries if depth testing has been enabled via cogl_set_depth_test_enable()
*
* Return value: %TRUE if depth testing is enabled, and %FALSE otherwise
*
* Deprecated: 1.4: Use cogl_material_get_depth_test_enabled()
* instead.
*/
gboolean
cogl_get_depth_test_enabled (void);
/**
* cogl_set_backface_culling_enabled:
* @setting: %TRUE to enable backface culling or %FALSE to disable.
*
* Sets whether textures positioned so that their backface is showing
* should be hidden. This can be used to efficiently draw two-sided
* textures or fully closed cubes without enabling depth testing. This
* only affects calls to the cogl_rectangle* family of functions and
* cogl_vertex_buffer_draw*. Backface culling is disabled by default.
*/
void
cogl_set_backface_culling_enabled (gboolean setting);
/**
* cogl_get_backface_culling_enabled:
*
* Queries if backface culling has been enabled via
* cogl_set_backface_culling_enabled()
*
* Return value: %TRUE if backface culling is enabled, and %FALSE otherwise
*/
gboolean
cogl_get_backface_culling_enabled (void);
/**
* cogl_set_fog:
* @fog_color: The color of the fog
* @mode: A #CoglFogMode that determines the equation used to calculate the
* fogging blend factor.
* @density: Used by %COGL_FOG_MODE_EXPONENTIAL and by
* %COGL_FOG_MODE_EXPONENTIAL_SQUARED equations.
* @z_near: Position along Z axis where no fogging should be applied
* @z_far: Position along Z axis where full fogging should be applied
*
* Enables fogging. Fogging causes vertices that are further away from the eye
* to be rendered with a different color. The color is determined according to
* the chosen fog mode; at it's simplest the color is linearly interpolated so
* that vertices at @z_near are drawn fully with their original color and
* vertices at @z_far are drawn fully with @fog_color. Fogging will remain
* enabled until you call cogl_disable_fog().
*
* <note>The fogging functions only work correctly when primitives use
* unmultiplied alpha colors. By default Cogl will premultiply textures
* and cogl_set_source_color() will premultiply colors, so unless you
* explicitly load your textures requesting an unmultiplied internal format
* and use cogl_material_set_color() you can only use fogging with fully
* opaque primitives. This might improve in the future when we can depend
* on fragment shaders.</note>
*/
void
cogl_set_fog (const CoglColor *fog_color,
CoglFogMode mode,
float density,
float z_near,
float z_far);
/**
* cogl_disable_fog:
*
* This function disables fogging, so primitives drawn afterwards will not be
* blended with any previously set fog color.
*/
void
cogl_disable_fog (void);
/**
* cogl_clear:
* @color: Background color to clear to
* @buffers: A mask of #CoglBufferBit<!-- -->'s identifying which auxiliary
* buffers to clear
*
* Clears all the auxiliary buffers identified in the @buffers mask, and if
* that includes the color buffer then the specified @color is used.
*/
void
cogl_clear (const CoglColor *color,
unsigned long buffers);
/**
* cogl_set_source:
* @material: A #CoglMaterial
*
* This function changes the material at the top of the source stack.
* The material at the top of this stack defines the GPU state used to
* process subsequent primitives, such as rectangles drawn with
* cogl_rectangle() or vertices drawn using cogl_vertex_buffer_draw().
*
* Since: 1.0
*/
void
cogl_set_source (void *material);
/**
* cogl_get_source:
*
* Returns the current source material as previously set using
* cogl_set_source().
*
* <note>You should typically consider the returned material immutable
* and not try to change any of its properties unless you own a
* reference to that material. At times you may be able to get a
* reference to an internally managed materials and the result of
* modifying such materials is undefined.</note>
*
* Return value: The current source material.
*
* Since: 1.6
*/
void *
cogl_get_source (void);
/**
* cogl_push_source:
* @material: A #CoglMaterial
*
* Pushes the given @material to the top of the source stack. The
* material at the top of this stack defines the GPU state used to
* process later primitives as defined by cogl_set_source().
*
* Since: 1.6
*/
void
cogl_push_source (void *material);
/**
* cogl_pop_source:
*
* Removes the material at the top of the source stack. The material
* at the top of this stack defines the GPU state used to process
* later primitives as defined by cogl_set_source().
*
* Since: 1.6
*/
void
cogl_pop_source (void);
/**
* cogl_set_source_color:
* @color: a #CoglColor
*
* This is a convenience function for creating a solid fill source material
* from the given color. This color will be used for any subsequent drawing
* operation.
*
* The color will be premultiplied by Cogl, so the color should be
* non-premultiplied. For example: use (1.0, 0.0, 0.0, 0.5) for
* semi-transparent red.
*
* See also cogl_set_source_color4ub() and cogl_set_source_color4f()
* if you already have the color components.
*
* Since: 1.0
*/
void
cogl_set_source_color (const CoglColor *color);
/**
* cogl_set_source_color4ub:
* @red: value of the red channel, between 0 and 255
* @green: value of the green channel, between 0 and 255
* @blue: value of the blue channel, between 0 and 255
* @alpha: value of the alpha channel, between 0 and 255
*
* This is a convenience function for creating a solid fill source material
* from the given color using unsigned bytes for each component. This
* color will be used for any subsequent drawing operation.
*
* The value for each component is an unsigned byte in the range
* between 0 and 255.
*
* Since: 1.0
*/
void
cogl_set_source_color4ub (guint8 red,
guint8 green,
guint8 blue,
guint8 alpha);
/**
* cogl_set_source_color4f:
* @red: value of the red channel, between 0 and %1.0
* @green: value of the green channel, between 0 and %1.0
* @blue: value of the blue channel, between 0 and %1.0
* @alpha: value of the alpha channel, between 0 and %1.0
*
* This is a convenience function for creating a solid fill source material
* from the given color using normalized values for each component. This color
* will be used for any subsequent drawing operation.
*
* The value for each component is a fixed point number in the range
* between 0 and %1.0. If the values passed in are outside that
* range, they will be clamped.
*
* Since: 1.0
*/
void
cogl_set_source_color4f (float red,
float green,
float blue,
float alpha);
/**
* cogl_set_source_texture:
* @texture: The #CoglTexture you want as your source
*
* This is a convenience function for creating a material with the first
* layer set to @texture and setting that material as the source with
* cogl_set_source.
*
* Note: There is no interaction between calls to cogl_set_source_color
* and cogl_set_source_texture. If you need to blend a texture with a color then
* you can create a simple material like this:
* <programlisting>
* material = cogl_material_new ();
* cogl_material_set_color4ub (material, 0xff, 0x00, 0x00, 0x80);
* cogl_material_set_layer (material, 0, tex_handle);
* cogl_set_source (material);
* </programlisting>
*
* Since: 1.0
*/
void
cogl_set_source_texture (CoglTexture *texture);
/**
* SECTION:cogl-clipping
* @short_description: Fuctions for manipulating a stack of clipping regions
*
* To support clipping your geometry to rectangles or paths Cogl exposes a
* stack based API whereby each clip region you push onto the stack is
* intersected with the previous region.
*/
#ifndef COGL_DISABLE_DEPRECATED
/**
* cogl_clip_push_window_rect:
* @x_offset: left edge of the clip rectangle in window coordinates
* @y_offset: top edge of the clip rectangle in window coordinates
* @width: width of the clip rectangle
* @height: height of the clip rectangle
*
* Specifies a rectangular clipping area for all subsequent drawing
* operations. Any drawing commands that extend outside the rectangle
* will be clipped so that only the portion inside the rectangle will
* be displayed. The rectangle dimensions are not transformed by the
* current model-view matrix.
*
* The rectangle is intersected with the current clip region. To undo
* the effect of this function, call cogl_clip_pop().
*
* Deprecated: 1.2: Use cogl_clip_push_window_rectangle() instead
*/
void
cogl_clip_push_window_rect (float x_offset,
float y_offset,
float width,
float height) G_GNUC_DEPRECATED;
#endif /* COGL_DISABLE_DEPRECATED */
/**
* cogl_clip_push_window_rectangle:
* @x_offset: left edge of the clip rectangle in window coordinates
* @y_offset: top edge of the clip rectangle in window coordinates
* @width: width of the clip rectangle
* @height: height of the clip rectangle
*
* Specifies a rectangular clipping area for all subsequent drawing
* operations. Any drawing commands that extend outside the rectangle
* will be clipped so that only the portion inside the rectangle will
* be displayed. The rectangle dimensions are not transformed by the
* current model-view matrix.
*
* The rectangle is intersected with the current clip region. To undo
* the effect of this function, call cogl_clip_pop().
*
* Since: 1.2
*/
void
cogl_clip_push_window_rectangle (int x_offset,
int y_offset,
int width,
int height);
#ifndef COGL_DISABLE_DEPRECATED
/**
* cogl_clip_push:
* @x_offset: left edge of the clip rectangle
* @y_offset: top edge of the clip rectangle
* @width: width of the clip rectangle
* @height: height of the clip rectangle
*
* Specifies a rectangular clipping area for all subsequent drawing
* operations. Any drawing commands that extend outside the rectangle
* will be clipped so that only the portion inside the rectangle will
* be displayed. The rectangle dimensions are transformed by the
* current model-view matrix.
*
* The rectangle is intersected with the current clip region. To undo
* the effect of this function, call cogl_clip_pop().
*
* Deprecated: 1.2: The x, y, width, height arguments are inconsistent
* with other API that specify rectangles in model space, and when used
* with a coordinate space that puts the origin at the center and y+
* extending up, it's awkward to use. Please use cogl_clip_push_rectangle()
* instead
*/
void
cogl_clip_push (float x_offset,
float y_offset,
float width,
float height) G_GNUC_DEPRECATED;
#endif /* COGL_DISABLE_DEPRECATED */
/**
* cogl_clip_push_rectangle:
* @x0: x coordinate for top left corner of the clip rectangle
* @y0: y coordinate for top left corner of the clip rectangle
* @x1: x coordinate for bottom right corner of the clip rectangle
* @y1: y coordinate for bottom right corner of the clip rectangle
*
* Specifies a rectangular clipping area for all subsequent drawing
* operations. Any drawing commands that extend outside the rectangle
* will be clipped so that only the portion inside the rectangle will
* be displayed. The rectangle dimensions are transformed by the
* current model-view matrix.
*
* The rectangle is intersected with the current clip region. To undo
* the effect of this function, call cogl_clip_pop().
*
* Since: 1.2
*/
void
cogl_clip_push_rectangle (float x0,
float y0,
float x1,
float y1);
/**
* cogl_clip_push_from_path_preserve:
*
* Sets a new clipping area using the current path. The current path
* is then cleared. The clipping area is intersected with the previous
* clipping area. To restore the previous clipping area, call
* cogl_clip_pop().
*
* Since: 1.0
*/
void
cogl_clip_push_from_path_preserve (void);
#ifdef COGL_ENABLE_EXPERIMENTAL_2_0_API
/**
* cogl_clip_push_primitive:
* @primitive: A #CoglPrimitive describing a flat 2D shape
* @bounds_x1: x coordinate for the top-left corner of the primitives
* bounds
* @bounds_y1: y coordinate for the top-left corner of the primitives
* bounds
* @bounds_x2: x coordinate for the top-left corner of the primitives
* bounds
* @bounds_y2: x coordinate for the bottom-right corner of the
* primitives bounds.
* @bounds_x1: y coordinate for the bottom-right corner of the
* primitives bounds.
*
* Sets a new clipping area using a 2D shaped described with a
* #CoglPrimitive. The shape must not contain self overlapping
* geometry and must lie on a single 2D plane. A bounding box of the
* 2D shape in local coordinates (the same coordinates used to
* describe the shape) must be given. It is acceptable for the bounds
* to be larger than the true bounds but behaviour is undefined if the
* bounds are smaller than the true bounds.
*
* The primitive is transformed by the current model-view matrix and
* the silhouette is intersected with the previous clipping area. To
* restore the previous clipping area, call
* cogl_clip_pop().
*
* Since: 1.10
* Stability: unstable
*/
void
cogl_clip_push_primitive (CoglPrimitive *primitive,
float bounds_x1,
float bounds_y1,
float bounds_x2,
float bounds_y2);
#endif
/**
* cogl_clip_pop:
*
* Reverts the clipping region to the state before the last call to
* cogl_clip_push().
*/
void
cogl_clip_pop (void);
#ifndef COGL_DISABLE_DEPRECATED
/**
* cogl_clip_ensure:
*
* Ensures that the current clipping region has been set in GL. This
* will automatically be called before any Cogl primitives but it
* maybe be neccessary to call if you are using raw GL calls with
* clipping.
*
* Deprecated: 1.2: Calling this function has no effect
*
* Since: 1.0
*/
void
cogl_clip_ensure (void) G_GNUC_DEPRECATED;
/**
* cogl_clip_stack_save:
*
* Save the entire state of the clipping stack and then clear all
* clipping. The previous state can be returned to with
* cogl_clip_stack_restore(). Each call to cogl_clip_push() after this
* must be matched by a call to cogl_clip_pop() before calling
* cogl_clip_stack_restore().
*
* Deprecated: 1.2: This was originally added to allow us to save the
* clip stack when switching to an offscreen framebuffer, but it's
* not necessary anymore given that framebuffers now own separate
* clip stacks which will be automatically switched between when a
* new buffer is set. Calling this function has no effect
*
* Since: 0.8.2
*/
void
cogl_clip_stack_save (void) G_GNUC_DEPRECATED;
/**
* cogl_clip_stack_restore:
*
* Restore the state of the clipping stack that was previously saved
* by cogl_clip_stack_save().
*
* Deprecated: 1.2: This was originally added to allow us to restore
* the clip stack when switching back from an offscreen framebuffer,
* but it's not necessary anymore given that framebuffers now own
* separate clip stacks which will be automatically switched between
* when a new buffer is set. Calling this function has no effect
*
* Since: 0.8.2
*/
void
cogl_clip_stack_restore (void) G_GNUC_DEPRECATED;
#endif /* COGL_DISABLE_DEPRECATED */
/**
* cogl_set_framebuffer:
* @buffer: A #CoglFramebuffer object, either onscreen or offscreen.
*
* This redirects all subsequent drawing to the specified framebuffer. This can
* either be an offscreen buffer created with cogl_offscreen_new_to_texture ()
* or in the future it may be an onscreen framebuffers too.
*
* Since: 1.2
*/
void
cogl_set_framebuffer (CoglFramebuffer *buffer);
/**
* cogl_push_framebuffer:
* @buffer: A #CoglFramebuffer object, either onscreen or offscreen.
*
* Redirects all subsequent drawing to the specified framebuffer. This can
* either be an offscreen buffer created with cogl_offscreen_new_to_texture ()
* or in the future it may be an onscreen framebuffer too.
*
* You should understand that a framebuffer owns the following state:
* <itemizedlist>
* <listitem><simpara>The projection matrix</simpara></listitem>
* <listitem><simpara>The modelview matrix stack</simpara></listitem>
* <listitem><simpara>The viewport</simpara></listitem>
* <listitem><simpara>The clip stack</simpara></listitem>
* </itemizedlist>
* So these items will automatically be saved and restored when you
* push and pop between different framebuffers.
*
* Also remember a newly allocated framebuffer will have an identity matrix for
* the projection and modelview matrices which gives you a coordinate space
* like OpenGL with (-1, -1) corresponding to the top left of the viewport,
* (1, 1) corresponding to the bottom right and +z coming out towards the
* viewer.
*
* If you want to set up a coordinate space like Clutter does with (0, 0)
* corresponding to the top left and (framebuffer_width, framebuffer_height)
* corresponding to the bottom right you can do so like this:
*
* |[
* static void
* setup_viewport (unsigned int width,
* unsigned int height,
* float fovy,
* float aspect,
* float z_near,
* float z_far)
* {
* float z_camera;
* CoglMatrix projection_matrix;
* CoglMatrix mv_matrix;
*
* cogl_set_viewport (0, 0, width, height);
* cogl_perspective (fovy, aspect, z_near, z_far);
*
* cogl_get_projection_matrix (&amp;projection_matrix);
* z_camera = 0.5 * projection_matrix.xx;
*
* cogl_matrix_init_identity (&amp;mv_matrix);
* cogl_matrix_translate (&amp;mv_matrix, -0.5f, -0.5f, -z_camera);
* cogl_matrix_scale (&amp;mv_matrix, 1.0f / width, -1.0f / height, 1.0f / width);
* cogl_matrix_translate (&amp;mv_matrix, 0.0f, -1.0 * height, 0.0f);
* cogl_set_modelview_matrix (&amp;mv_matrix);
* }
*
* static void
* my_init_framebuffer (ClutterStage *stage,
* CoglFramebuffer *framebuffer,
* unsigned int framebuffer_width,
* unsigned int framebuffer_height)
* {
* ClutterPerspective perspective;
*
* clutter_stage_get_perspective (stage, &perspective);
*
* cogl_push_framebuffer (framebuffer);
* setup_viewport (framebuffer_width,
* framebuffer_height,
* perspective.fovy,
* perspective.aspect,
* perspective.z_near,
* perspective.z_far);
* }
* ]|
*
* The previous framebuffer can be restored by calling cogl_pop_framebuffer()
*
* Since: 1.2
*/
void
cogl_push_framebuffer (CoglFramebuffer *buffer);
/**
* cogl_pop_framebuffer:
*
* Restores the framebuffer that was previously at the top of the stack.
* All subsequent drawing will be redirected to this framebuffer.
*
* Since: 1.2
*/
void
cogl_pop_framebuffer (void);
#ifndef COGL_DISABLE_DEPRECATED
/**
* cogl_set_draw_buffer:
* @target: A #CoglBufferTarget that specifies what kind of framebuffer you
* are setting as the render target.
* @offscreen: If you are setting a framebuffer of type COGL_OFFSCREEN_BUFFER
* then this is a CoglHandle for the offscreen buffer.
*
* Redirects all subsequent drawing to the specified framebuffer. This
* can either be an offscreen buffer created with
* cogl_offscreen_new_to_texture () or you can revert to your original
* on screen window buffer.
*
* Deprecated: 1.2: The target argument was redundant since we could look at
* the type of CoglHandle given instead.
*/
void
cogl_set_draw_buffer (CoglBufferTarget target,
CoglHandle offscreen) G_GNUC_DEPRECATED;
/**
* cogl_push_draw_buffer:
*
* Save cogl_set_draw_buffer() state.
*
* Deprecated: 1.2: The draw buffer API was replaced with a framebuffer API
*/
void
cogl_push_draw_buffer (void) G_GNUC_DEPRECATED;
/**
* cogl_pop_draw_buffer:
*
* Restore cogl_set_draw_buffer() state.
*
* Deprecated: 1.2: The draw buffer API was replaced with a framebuffer API
*/
void
cogl_pop_draw_buffer (void) G_GNUC_DEPRECATED;
#endif /* COGL_DISABLE_DEPRECATED */
/**
* cogl_read_pixels:
* @x: The window x position to start reading from
* @y: The window y position to start reading from
* @width: The width of the rectangle you want to read
* @height: The height of the rectangle you want to read
* @source: Identifies which auxillary buffer you want to read
* (only COGL_READ_PIXELS_COLOR_BUFFER supported currently)
* @format: The pixel format you want the result in
* (only COGL_PIXEL_FORMAT_RGBA_8888 supported currently)
* @pixels: The location to write the pixel data.
*
* This reads a rectangle of pixels from the current framebuffer where
* position (0, 0) is the top left. The pixel at (x, y) is the first
* read, and the data is returned with a rowstride of (width * 4).
*
* Currently Cogl assumes that the framebuffer is in a premultiplied
* format so if @format is non-premultiplied it will convert it. To
* read the pixel values without any conversion you should either
* specify a format that doesn't use an alpha channel or use one of
* the formats ending in PRE.
*/
void
cogl_read_pixels (int x,
int y,
int width,
int height,
CoglReadPixelsFlags source,
CoglPixelFormat format,
guint8 *pixels);
/**
* cogl_flush:
*
* This function should only need to be called in exceptional circumstances.
*
* As an optimization Cogl drawing functions may batch up primitives
* internally, so if you are trying to use raw GL outside of Cogl you stand a
* better chance of being successful if you ask Cogl to flush any batched
* geometry before making your state changes.
*
* It only ensure that the underlying driver is issued all the commands
* necessary to draw the batched primitives. It provides no guarantees about
* when the driver will complete the rendering.
*
* This provides no guarantees about the GL state upon returning and to avoid
* confusing Cogl you should aim to restore any changes you make before
* resuming use of Cogl.
*
* If you are making state changes with the intention of affecting Cogl drawing
* primitives you are 100% on your own since you stand a good chance of
* conflicting with Cogl internals. For example clutter-gst which currently
* uses direct GL calls to bind ARBfp programs will very likely break when Cogl
* starts to use ARBfb programs itself for the material API.
*
* Since: 1.0
*/
void
cogl_flush (void);
/**
* cogl_begin_gl:
*
* We do not advise nor reliably support the interleaving of raw GL drawing and
* Cogl drawing functions, but if you insist, cogl_begin_gl() and cogl_end_gl()
* provide a simple mechanism that may at least give you a fighting chance of
* succeeding.
*
* Note: this doesn't help you modify the behaviour of Cogl drawing functions
* through the modification of GL state; that will never be reliably supported,
* but if you are trying to do something like:
*
* |[
* {
* - setup some OpenGL state.
* - draw using OpenGL (e.g. glDrawArrays() )
* - reset modified OpenGL state.
* - continue using Cogl to draw
* }
* ]|
*
* You should surround blocks of drawing using raw GL with cogl_begin_gl()
* and cogl_end_gl():
*
* |[
* {
* cogl_begin_gl ();
* - setup some OpenGL state.
* - draw using OpenGL (e.g. glDrawArrays() )
* - reset modified OpenGL state.
* cogl_end_gl ();
* - continue using Cogl to draw
* }
* ]|
*
* Don't ever try and do:
*
* |[
* {
* - setup some OpenGL state.
* - use Cogl to draw
* - reset modified OpenGL state.
* }
* ]|
*
* When the internals of Cogl evolves, this is very liable to break.
*
* This function will flush all batched primitives, and subsequently flush
* all internal Cogl state to OpenGL as if it were going to draw something
* itself.
*
* The result is that the OpenGL modelview matrix will be setup; the state
* corresponding to the current source material will be set up and other world
* state such as backface culling, depth and fogging enabledness will be sent
* to OpenGL.
*
* <note>No special material state is flushed, so if you want Cogl to setup a
* simplified material state it is your responsibility to set a simple source
* material before calling cogl_begin_gl(). E.g. by calling
* cogl_set_source_color4ub().</note>
*
* <note>It is your responsibility to restore any OpenGL state that you modify
* to how it was after calling cogl_begin_gl() if you don't do this then the
* result of further Cogl calls is undefined.</note>
*
* <note>You can not nest begin/end blocks.</note>
*
* Again we would like to stress, we do not advise the use of this API and if
* possible we would prefer to improve Cogl than have developers require raw
* OpenGL.
*
* Since: 1.0
*/
void
cogl_begin_gl (void);
/**
* cogl_end_gl:
*
* This is the counterpart to cogl_begin_gl() used to delimit blocks of drawing
* code using raw OpenGL. Please refer to cogl_begin_gl() for full details.
*
* Since: 1.0
*/
void
cogl_end_gl (void);
G_END_DECLS
#endif /* __COGL_1_CONTEXT_H__ */