mutter/cogl/cogl-sdl.h

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/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2012 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_SDL_H__
#define __COGL_SDL_H__
/* NB: this is a top-level header that can be included directly but we
* want to be careful not to define __COGL_H_INSIDE__ when this is
* included internally while building Cogl itself since
* __COGL_H_INSIDE__ is used in headers to guard public vs private api
* definitions
*/
#ifndef COGL_COMPILATION
/* Note: When building Cogl .gir we explicitly define
* __COGL_H_INSIDE__ */
#ifndef __COGL_H_INSIDE__
#define __COGL_H_INSIDE__
#define __COGL_SDL_H_MUST_UNDEF_COGL_H_INSIDE__
#endif
#endif /* COGL_COMPILATION */
#include <cogl/cogl-context.h>
#include <cogl/cogl-onscreen.h>
#include <SDL.h>
#ifdef _MSC_VER
/* We need to link to SDL.lib/SDLmain.lib
* if we are using Cogl
* that uses the SDL winsys
*/
#pragma comment (lib, "SDL.lib")
#pragma comment (lib, "SDLmain.lib")
#endif
COGL_BEGIN_DECLS
/**
* SECTION:cogl-sdl
* @short_description: Integration api for the Simple DirectMedia
* Layer library.
*
* Cogl is a portable graphics api that can either be used standalone
* or alternatively integrated with certain existing frameworks. This
* api enables Cogl to be used in conjunction with the Simple
* DirectMedia Layer library.
*
* Using this API a typical SDL application would look something like
* this:
* |[
* MyAppData data;
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 14:28:27 -04:00
* CoglError *error = NULL;
*
* data.ctx = cogl_sdl_context_new (SDL_USEREVENT, &error);
* if (!data.ctx)
* {
* fprintf (stderr, "Failed to create context: %s\n",
* error->message);
* return 1;
* }
*
* my_application_setup (&data);
*
* data.redraw_queued = TRUE;
* while (!data.quit)
* {
* while (!data.quit)
* {
* if (!SDL_PollEvent (&event))
* {
* if (data.redraw_queued)
* break;
*
* cogl_sdl_idle (ctx);
* if (!SDL_WaitEvent (&event))
* {
* fprintf (stderr, "Error waiting for SDL events");
* return 1;
* }
* }
*
* handle_event (&data, &event);
* cogl_sdl_handle_event (ctx, &event);
* }
*
* data.redraw_queued = redraw (&data);
* }
* ]|
*/
/**
* cogl_sdl_context_new:
* @type: An SDL user event type between <constant>SDL_USEREVENT</constant> and
* <constant>SDL_NUMEVENTS</constant> - 1
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 14:28:27 -04:00
* @error: A CoglError return location.
*
* This is a convenience function for creating a new #CoglContext for
* use with SDL and specifying what SDL user event type Cogl can use
* as a way to interrupt SDL_WaitEvent().
*
* This function is equivalent to the following code:
* |[
* CoglRenderer *renderer = cogl_renderer_new ();
* CoglDisplay *display;
*
* cogl_renderer_set_winsys_id (renderer, COGL_WINSYS_ID_SDL);
*
* cogl_sdl_renderer_set_event_type (renderer, type);
*
* if (!cogl_renderer_connect (renderer, error))
* return NULL;
*
* display = cogl_display_new (renderer, NULL);
* if (!cogl_display_setup (display, error))
* return NULL;
*
* return cogl_context_new (display, error);
* ]|
*
* <note>SDL applications are required to either use this API or
* to manually create a #CoglRenderer and call
* cogl_sdl_renderer_set_event_type().</note>
*
* Since: 2.0
* Stability: unstable
*/
CoglContext *
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 14:28:27 -04:00
cogl_sdl_context_new (int type, CoglError **error);
/**
* cogl_sdl_renderer_set_event_type:
* @renderer: A #CoglRenderer
* @type: An SDL user event type between <constant>SDL_USEREVENT</constant> and
* <constant>SDL_NUMEVENTS</constant> - 1
*
* Tells Cogl what SDL user event type it can use as a way to
* interrupt SDL_WaitEvent() to ensure that cogl_sdl_handle_event()
* will be called in a finite amount of time.
*
* <note>This should only be called on an un-connected
* @renderer.</note>
*
* <note>For convenience most simple applications can use
* cogl_sdl_context_new() if they don't want to manually create
* #CoglRenderer and #CoglDisplay objects during
* initialization.</note>
*
* Since: 2.0
* Stability: unstable
*/
void
cogl_sdl_renderer_set_event_type (CoglRenderer *renderer, int type);
/**
* cogl_sdl_renderer_get_event_type:
* @renderer: A #CoglRenderer
*
* Queries what SDL user event type Cogl is using as a way to
* interrupt SDL_WaitEvent(). This is set either using
* cogl_sdl_context_new or by using
* cogl_sdl_renderer_set_event_type().
*
* Since: 2.0
* Stability: unstable
*/
int
cogl_sdl_renderer_get_event_type (CoglRenderer *renderer);
/**
* cogl_sdl_handle_event:
* @context: A #CoglContext
* @event: An SDL event
*
* Passes control to Cogl so that it may dispatch any internal event
* callbacks in response to the given SDL @event. This function must
* be called for every SDL event.
*
* Since: 2.0
* Stability: unstable
*/
void
cogl_sdl_handle_event (CoglContext *context, SDL_Event *event);
/**
* cogl_sdl_idle:
* @context: A #CoglContext
*
* Notifies Cogl that the application is idle and about to call
* SDL_WaitEvent(). Cogl may use this to run low priority book keeping
* tasks.
*
* Since: 2.0
* Stability: unstable
*/
void
cogl_sdl_idle (CoglContext *context);
#if SDL_MAJOR_VERSION >= 2
/**
* cogl_sdl_onscreen_get_window:
* @onscreen: A #CoglOnscreen
*
* Returns: the underlying SDL_Window associated with an onscreen framebuffer.
*
* Since: 2.0
* Stability: unstable
*/
SDL_Window *
cogl_sdl_onscreen_get_window (CoglOnscreen *onscreen);
#endif /* SDL_MAJOR_VERSION */
COGL_END_DECLS
/* The gobject introspection scanner seems to parse public headers in
* isolation which means we need to be extra careful about how we
* define and undefine __COGL_H_INSIDE__ used to detect when internal
* headers are incorrectly included by developers. In the gobject
* introspection case we have to manually define __COGL_H_INSIDE__ as
* a commandline argument for the scanner which means we must be
* careful not to undefine it in a header...
*/
#ifdef __COGL_SDL_H_MUST_UNDEF_COGL_H_INSIDE__
#undef __COGL_H_INSIDE__
#undef __COGL_SDL_H_MUST_UNDEF_COGL_H_INSIDE__
#endif
#endif /* __COGL_SDL_H__ */