mutter/cogl/cogl-context.h

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/*
* 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(COGL_COMPILATION)
#error "Only <cogl/cogl.h> can be included directly."
#endif
#ifndef __COGL_CONTEXT_H__
#define __COGL_CONTEXT_H__
/* We forward declare the CoglContext type here to avoid some circular
* dependency issues with the following headers.
*/
typedef struct _CoglContext CoglContext;
#include <cogl/cogl-defines.h>
#include <cogl/cogl-display.h>
#include <cogl/cogl-primitive.h>
#ifdef COGL_HAS_EGL_PLATFORM_ANDROID_SUPPORT
#include <android/native_window.h>
#endif
COGL_BEGIN_DECLS
/**
* SECTION:cogl-context
* @short_description: The top level application context.
*
* A #CoglContext is the top most sandbox of Cogl state for an
* application or toolkit. Its main purpose is to act as a sandbox
* for the memory management of state objects. Normally an application
* will only create a single context since there is no way to share
* resources between contexts.
*
* For those familiar with OpenGL or perhaps Cairo it should be
* understood that unlike these APIs a Cogl context isn't a rendering
* context as such. In other words Cogl doesn't aim to provide a state
* machine style model for configuring rendering parameters. Most
* rendering state in Cogl is directly associated with user managed
* objects called pipelines and geometry is drawn with a specific
* pipeline object to a framebuffer object and those 3 things fully
* define the state for drawing. This is an important part of Cogl's
* design since it helps you write orthogonal rendering components
* that can all access the same GPU without having to worry about
* what state other components have left you with.
*
* <note><para>Cogl does not maintain internal references to the context for
* resources that depend on the context so applications. This is to
* help applications control the lifetime a context without us needing to
* introduce special api to handle the breakup of internal circular
* references due to internal resources and caches associated with the
* context.
*
* One a context has been destroyed then all directly or indirectly
* dependant resources will be in an inconsistent state and should not
* be manipulated or queried in any way.
*
* For applications that rely on the operating system to clean up
* resources this policy shouldn't affect them, but for applications
* that need to carefully destroy and re-create Cogl contexts multiple
* times throughout their lifetime (such as Android applications) they
* should be careful to destroy all context dependant resources, such as
* framebuffers or textures etc before unrefing and destroying the
* context.</para></note>
*/
#ifdef COGL_ENABLE_EXPERIMENTAL_API
#define COGL_CONTEXT(OBJECT) ((CoglContext *)OBJECT)
/**
* cogl_context_new:
* @display: A #CoglDisplay pointer
Adds CoglError api Although we use GLib internally in Cogl we would rather not leak GLib api through Cogl's own api, except through explicitly namespaced cogl_glib_ / cogl_gtype_ feature apis. One of the benefits we see to not leaking GLib through Cogl's public API is that documentation for Cogl won't need to first introduce the Glib API to newcomers, thus hopefully lowering the barrier to learning Cogl. This patch provides a Cogl specific typedef for reporting runtime errors which by no coincidence matches the typedef for GError exactly. If Cogl is built with --enable-glib (default) then developers can even safely assume that a CoglError is a GError under the hood. This patch also enforces a consistent policy for when NULL is passed as an error argument and an error is thrown. In this case we log the error and abort the application, instead of silently ignoring it. In common cases where nothing has been implemented to handle a particular error and/or where applications are just printing the error and aborting themselves then this saves some typing. This also seems more consistent with language based exceptions which usually cause a program to abort if they are not explicitly caught (which passing a non-NULL error signifies in this case) Since this policy for NULL error pointers is stricter than the standard GError convention, there is a clear note in the documentation to warn developers that are used to using the GError api. Reviewed-by: Neil Roberts <neil@linux.intel.com> (cherry picked from commit b068d5ea09ab32c37e8c965fc8582c85d1b2db46) Note: Since we can't change the Cogl 1.x api the patch was changed to not rename _error_quark() functions to be _error_domain() functions and although it's a bit ugly, instead of providing our own CoglError type that's compatible with GError we simply #define CoglError to GError unless Cogl is built with glib disabled. Note: this patch does technically introduce an API break since it drops the cogl_error_get_type() symbol generated by glib-mkenum (Since the CoglError enum was replaced by a CoglSystemError enum) but for now we are assuming that this will not affect anyone currently using the Cogl API. If this does turn out to be a problem in practice then we would be able to fix this my manually copying an implementation of cogl_error_get_type() generated by glib-mkenum into a compatibility source file and we could also define the original COGL_ERROR_ enums for compatibility too. Note: another minor concern with cherry-picking this patch to the 1.14 branch is that an api scanner would be lead to believe that some APIs have changed, and for example the gobject-introspection parser which understands the semantics of GError will not understand the semantics of CoglError. We expect most people that have tried to use gobject-introspection with Cogl already understand though that it is not well suited to generating bindings of the Cogl api anyway and we aren't aware or anyone depending on such bindings for apis involving GErrors. (GnomeShell only makes very-very minimal use of Cogl via the gjs bindings for the cogl_rectangle and cogl_color apis.) The main reason we have cherry-picked this patch to the 1.14 branch even given the above concerns is that without it it would become very awkward for us to cherry-pick other beneficial patches from master.
2012-08-31 18:28:27 +00:00
* @error: A CoglError return location.
*
* Creates a new #CoglContext which acts as an application sandbox
* for any state objects that are allocated.
*
* Return value: (transfer full): A newly allocated #CoglContext
* Since: 1.8
* Stability: unstable
*/
CoglContext *
cogl_context_new (CoglDisplay *display,
Adds CoglError api Although we use GLib internally in Cogl we would rather not leak GLib api through Cogl's own api, except through explicitly namespaced cogl_glib_ / cogl_gtype_ feature apis. One of the benefits we see to not leaking GLib through Cogl's public API is that documentation for Cogl won't need to first introduce the Glib API to newcomers, thus hopefully lowering the barrier to learning Cogl. This patch provides a Cogl specific typedef for reporting runtime errors which by no coincidence matches the typedef for GError exactly. If Cogl is built with --enable-glib (default) then developers can even safely assume that a CoglError is a GError under the hood. This patch also enforces a consistent policy for when NULL is passed as an error argument and an error is thrown. In this case we log the error and abort the application, instead of silently ignoring it. In common cases where nothing has been implemented to handle a particular error and/or where applications are just printing the error and aborting themselves then this saves some typing. This also seems more consistent with language based exceptions which usually cause a program to abort if they are not explicitly caught (which passing a non-NULL error signifies in this case) Since this policy for NULL error pointers is stricter than the standard GError convention, there is a clear note in the documentation to warn developers that are used to using the GError api. Reviewed-by: Neil Roberts <neil@linux.intel.com> (cherry picked from commit b068d5ea09ab32c37e8c965fc8582c85d1b2db46) Note: Since we can't change the Cogl 1.x api the patch was changed to not rename _error_quark() functions to be _error_domain() functions and although it's a bit ugly, instead of providing our own CoglError type that's compatible with GError we simply #define CoglError to GError unless Cogl is built with glib disabled. Note: this patch does technically introduce an API break since it drops the cogl_error_get_type() symbol generated by glib-mkenum (Since the CoglError enum was replaced by a CoglSystemError enum) but for now we are assuming that this will not affect anyone currently using the Cogl API. If this does turn out to be a problem in practice then we would be able to fix this my manually copying an implementation of cogl_error_get_type() generated by glib-mkenum into a compatibility source file and we could also define the original COGL_ERROR_ enums for compatibility too. Note: another minor concern with cherry-picking this patch to the 1.14 branch is that an api scanner would be lead to believe that some APIs have changed, and for example the gobject-introspection parser which understands the semantics of GError will not understand the semantics of CoglError. We expect most people that have tried to use gobject-introspection with Cogl already understand though that it is not well suited to generating bindings of the Cogl api anyway and we aren't aware or anyone depending on such bindings for apis involving GErrors. (GnomeShell only makes very-very minimal use of Cogl via the gjs bindings for the cogl_rectangle and cogl_color apis.) The main reason we have cherry-picked this patch to the 1.14 branch even given the above concerns is that without it it would become very awkward for us to cherry-pick other beneficial patches from master.
2012-08-31 18:28:27 +00:00
CoglError **error);
/**
* cogl_context_get_display:
* @context: A #CoglContext pointer
*
* Retrieves the #CoglDisplay that is internally associated with the
* given @context. This will return the same #CoglDisplay that was
* passed to cogl_context_new() or if %NULL was passed to
* cogl_context_new() then this function returns a pointer to the
* display that was automatically setup internally.
*
* Return value: (transfer none): The #CoglDisplay associated with the
* given @context.
* Since: 1.8
* Stability: unstable
*/
CoglDisplay *
cogl_context_get_display (CoglContext *context);
/**
* cogl_context_get_renderer:
* @context: A #CoglContext pointer
*
* Retrieves the #CoglRenderer that is internally associated with the
* given @context. This will return the same #CoglRenderer that was
* passed to cogl_display_new() or if %NULL was passed to
* cogl_display_new() or cogl_context_new() then this function returns
* a pointer to the renderer that was automatically connected
* internally.
*
* Return value: (transfer none): The #CoglRenderer associated with the
* given @context.
* Since: 1.16
* Stability: unstable
*/
CoglRenderer *
cogl_context_get_renderer (CoglContext *context);
#ifdef COGL_HAS_EGL_PLATFORM_ANDROID_SUPPORT
/**
* cogl_android_set_native_window:
* @window: A native Android window
*
* Allows Android applications to inform Cogl of the native window
* that they have been given which Cogl can render too. On Android
* this API must be used before creating a #CoglRenderer, #CoglDisplay
* and #CoglContext.
*
* Since: 1.8
* Stability: unstable
*/
void
cogl_android_set_native_window (ANativeWindow *window);
#endif
/**
* cogl_is_context:
* @object: An object or %NULL
*
* Gets whether the given object references an existing context object.
*
* Return value: %TRUE if the @object references a #CoglContext,
* %FALSE otherwise
*
* Since: 1.10
* Stability: Unstable
*/
CoglBool
cogl_is_context (void *object);
#endif /* COGL_ENABLE_EXPERIMENTAL_2_0_API */
/* XXX: not guarded by the EXPERIMENTAL_API defines to avoid
* upsetting glib-mkenums, but this can still be considered implicitly
* experimental since it's only useable with experimental API... */
/**
* CoglFeatureID:
* @COGL_FEATURE_ID_TEXTURE_NPOT_BASIC: The hardware supports non power
* of two textures, but you also need to check the
* %COGL_FEATURE_ID_TEXTURE_NPOT_MIPMAP and %COGL_FEATURE_ID_TEXTURE_NPOT_REPEAT
* features to know if the hardware supports npot texture mipmaps
* or repeat modes other than
* %COGL_PIPELINE_WRAP_MODE_CLAMP_TO_EDGE respectively.
* @COGL_FEATURE_ID_TEXTURE_NPOT_MIPMAP: Mipmapping is supported in
* conjuntion with non power of two textures.
* @COGL_FEATURE_ID_TEXTURE_NPOT_REPEAT: Repeat modes other than
* %COGL_PIPELINE_WRAP_MODE_CLAMP_TO_EDGE are supported by the
* hardware.
* @COGL_FEATURE_ID_TEXTURE_NPOT: Non power of two textures are supported
* by the hardware. This is a equivalent to the
* %COGL_FEATURE_ID_TEXTURE_NPOT_BASIC, %COGL_FEATURE_ID_TEXTURE_NPOT_MIPMAP
* and %COGL_FEATURE_ID_TEXTURE_NPOT_REPEAT features combined.
* @COGL_FEATURE_ID_TEXTURE_RECTANGLE: Support for rectangular
* textures with non-normalized texture coordinates.
* @COGL_FEATURE_ID_TEXTURE_3D: 3D texture support
* @COGL_FEATURE_ID_OFFSCREEN: Offscreen rendering support
* @COGL_FEATURE_ID_OFFSCREEN_MULTISAMPLE: Multisample support for
* offscreen framebuffers
* @COGL_FEATURE_ID_ONSCREEN_MULTIPLE: Multiple onscreen framebuffers
* supported.
* @COGL_FEATURE_ID_GLSL: GLSL support
* @COGL_FEATURE_ID_ARBFP: ARBFP support
* @COGL_FEATURE_ID_UNSIGNED_INT_INDICES: Set if
* %COGL_INDICES_TYPE_UNSIGNED_INT is supported in
* cogl_indices_new().
* @COGL_FEATURE_ID_DEPTH_RANGE: cogl_pipeline_set_depth_range() support
* @COGL_FEATURE_ID_POINT_SPRITE: Whether
* cogl_pipeline_set_layer_point_sprite_coords_enabled() is supported.
* @COGL_FEATURE_ID_MAP_BUFFER_FOR_READ: Whether cogl_buffer_map() is
* supported with CoglBufferAccess including read support.
* @COGL_FEATURE_ID_MAP_BUFFER_FOR_WRITE: Whether cogl_buffer_map() is
* supported with CoglBufferAccess including write support.
* @COGL_FEATURE_ID_MIRRORED_REPEAT: Whether
* %COGL_PIPELINE_WRAP_MODE_MIRRORED_REPEAT is supported.
* @COGL_FEATURE_ID_SWAP_BUFFERS_EVENT:
* Available if the window system supports reporting an event
* for swap buffer completions.
* @COGL_FEATURE_ID_GLES2_CONTEXT: Whether creating new GLES2 contexts is
* suported.
* @COGL_FEATURE_ID_DEPTH_TEXTURE: Whether #CoglFramebuffer support rendering
* the depth buffer to a texture.
* @COGL_FEATURE_ID_PRESENTATION_TIME: Whether frame presentation
* time stamps will be recorded in #CoglFrameInfo objects.
*
* All the capabilities that can vary between different GPUs supported
* by Cogl. Applications that depend on any of these features should explicitly
* check for them using cogl_has_feature() or cogl_has_features().
*
* Since: 1.10
*/
typedef enum _CoglFeatureID
{
COGL_FEATURE_ID_TEXTURE_NPOT_BASIC = 1,
COGL_FEATURE_ID_TEXTURE_NPOT_MIPMAP,
COGL_FEATURE_ID_TEXTURE_NPOT_REPEAT,
COGL_FEATURE_ID_TEXTURE_NPOT,
COGL_FEATURE_ID_TEXTURE_RECTANGLE,
COGL_FEATURE_ID_TEXTURE_3D,
COGL_FEATURE_ID_GLSL,
COGL_FEATURE_ID_ARBFP,
COGL_FEATURE_ID_OFFSCREEN,
COGL_FEATURE_ID_OFFSCREEN_MULTISAMPLE,
COGL_FEATURE_ID_ONSCREEN_MULTIPLE,
COGL_FEATURE_ID_UNSIGNED_INT_INDICES,
COGL_FEATURE_ID_DEPTH_RANGE,
COGL_FEATURE_ID_POINT_SPRITE,
COGL_FEATURE_ID_MAP_BUFFER_FOR_READ,
COGL_FEATURE_ID_MAP_BUFFER_FOR_WRITE,
COGL_FEATURE_ID_MIRRORED_REPEAT,
COGL_FEATURE_ID_SWAP_BUFFERS_EVENT,
COGL_FEATURE_ID_GLES2_CONTEXT,
COGL_FEATURE_ID_DEPTH_TEXTURE,
COGL_FEATURE_ID_PRESENTATION_TIME,
COGL_FEATURE_ID_FENCE,
/*< private >*/
_COGL_N_FEATURE_IDS /*< skip >*/
} CoglFeatureID;
#ifdef COGL_ENABLE_EXPERIMENTAL_API
/**
* cogl_has_feature:
* @context: A #CoglContext pointer
* @feature: A #CoglFeatureID
*
* Checks if a given @feature is currently available
*
* Cogl does not aim to be a lowest common denominator API, it aims to
* expose all the interesting features of GPUs to application which
* means applications have some responsibility to explicitly check
* that certain features are available before depending on them.
*
* Returns: %TRUE if the @feature is currently supported or %FALSE if
* not.
*
* Since: 1.10
* Stability: unstable
*/
CoglBool
cogl_has_feature (CoglContext *context, CoglFeatureID feature);
/**
* cogl_has_features:
* @context: A #CoglContext pointer
* @...: A 0 terminated list of CoglFeatureID<!-- -->s
*
* Checks if a list of features are all currently available.
*
* This checks all of the listed features using cogl_has_feature() and
* returns %TRUE if all the features are available or %FALSE
* otherwise.
*
* Return value: %TRUE if all the features are available, %FALSE
* otherwise.
*
* Since: 1.10
* Stability: unstable
*/
CoglBool
cogl_has_features (CoglContext *context, ...);
/**
* CoglFeatureCallback:
* @feature: A single feature currently supported by Cogl
* @user_data: A private pointer passed to cogl_foreach_feature().
*
* A callback used with cogl_foreach_feature() for enumerating all
* context level features supported by Cogl.
*
* Since: 0.10
* Stability: unstable
*/
typedef void (*CoglFeatureCallback) (CoglFeatureID feature, void *user_data);
/**
* cogl_foreach_feature:
* @context: A #CoglContext pointer
* @callback: A #CoglFeatureCallback called for each supported feature
* @user_data: Private data to pass to the callback
*
* Iterates through all the context level features currently supported
* for a given @context and for each feature @callback is called.
*
* Since: 1.10
* Stability: unstable
*/
void
cogl_foreach_feature (CoglContext *context,
CoglFeatureCallback callback,
void *user_data);
/**
* cogl_get_clock_time:
* @context: a #CoglContext pointer
*
* Returns the current time value from Cogl's internal clock. This
* clock is used for measuring times such as the presentation time
* in a #CoglFrameInfo.
*
* This method is meant for converting timestamps retrieved from Cogl
* to other time systems, and is not meant to be used as a standalone
* timing system. For that reason, if this function is called without
* having retrieved a valid (non-zero) timestamp from Cogl first, it
* may return 0 to indicate that Cogl has no active internal clock.
*
* Return value: the time value for the Cogl clock, in nanoseconds
* from an arbitrary point in time, or 0 if Cogl doesn't have an
* active internal clock.
* Since: 1.14
* Stability: unstable
*/
int64_t
cogl_get_clock_time (CoglContext *context);
#endif /* COGL_ENABLE_EXPERIMENTAL_API */
COGL_END_DECLS
#endif /* __COGL_CONTEXT_H__ */