gecko-dev/gfx/gl/GLContextProviderImpl.h
2017-08-02 17:09:37 -07:00

132 lines
5.4 KiB
C++

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef IN_GL_CONTEXT_PROVIDER_H
#error GLContextProviderImpl.h must only be included from GLContextProvider.h
#endif
#ifndef GL_CONTEXT_PROVIDER_NAME
#error GL_CONTEXT_PROVIDER_NAME not defined
#endif
#if defined(MOZ_WIDGET_ANDROID)
#include "GLTypes.h" // for EGLSurface and EGLConfig
#endif // defined(MOZ_WIDGET_ANDROID)
class GL_CONTEXT_PROVIDER_NAME
{
public:
/**
* Create a context that renders to the surface of the widget represented by
* the compositor widget that is passed in. The context is always created
* with an RGB pixel format, with no alpha, depth or stencil.
* If any of those features are needed, either use a framebuffer, or
* use CreateOffscreen.
*
* This context will attempt to share resources with all other window
* contexts. As such, it's critical that resources allocated that are not
* needed by other contexts be deleted before the context is destroyed.
*
* The GetSharedContext() method will return non-null if sharing
* was successful.
*
* Note: a context created for a widget /must not/ hold a strong
* reference to the widget; otherwise a cycle can be created through
* a GL layer manager.
*
* @param aCompositorWidget Widget whose surface to create a context for
* @param aForceAccelerated true if only accelerated contexts are allowed
*
* @return Context to use for the window
*/
static already_AddRefed<GLContext>
CreateForCompositorWidget(mozilla::widget::CompositorWidget* aCompositorWidget, bool aForceAccelerated);
/**
* Create a context that renders to the surface of the widget that is
* passed in. The context is always created with an RGB pixel format,
* with no alpha, depth or stencil. If any of those features are needed,
* either use a framebuffer, or use CreateOffscreen.
*
* This context will attempt to share resources with all other window
* contexts. As such, it's critical that resources allocated that are not
* needed by other contexts be deleted before the context is destroyed.
*
* The GetSharedContext() method will return non-null if sharing
* was successful.
*
* Note: a context created for a widget /must not/ hold a strong
* reference to the widget; otherwise a cycle can be created through
* a GL layer manager.
*
* @param aWidget Widget whose surface to create a context for
* @param aWebRender If the compositor is a WebRender compositor
* @param aForceAccelerated true if only accelerated contexts are allowed
*
* @return Context to use for the window
*/
static already_AddRefed<GLContext>
CreateForWindow(nsIWidget* aWidget, bool aWebRender, bool aForceAccelerated);
/**
* Create a context for offscreen rendering. The target of this
* context should be treated as opaque -- it might be a FBO, or a
* pbuffer, or some other construct. Users of this GLContext
* should bind framebuffer 0 directly to use this offscreen buffer.
*
* The offscreen context returned by this method will always have
* the ability to be rendered into a context created by a window.
* It might or might not share resources with the global context;
* query GetSharedContext() for a non-null result to check. If
* resource sharing can be avoided on the target platform, it will
* be, in order to isolate the offscreen context.
*
* @param size The initial size of this offscreen context.
* @param minCaps The required SurfaceCaps for this offscreen context. The resulting
* context *may* have more/better caps than requested, but it cannot
* have fewer/worse caps than requested.
* @param flags The set of CreateContextFlags to be used for this
* offscreen context.
*
* @return Context to use for offscreen rendering
*/
static already_AddRefed<GLContext>
CreateOffscreen(const mozilla::gfx::IntSize& size,
const SurfaceCaps& minCaps,
CreateContextFlags flags,
nsACString* const out_failureId);
// Just create a context. We'll add offscreen stuff ourselves.
static already_AddRefed<GLContext>
CreateHeadless(CreateContextFlags flags, nsACString* const out_failureId);
/**
* Create wrapping Gecko GLContext for external gl context.
*
* @param aContext External context which will be wrapped by Gecko GLContext.
* @param aSurface External surface which is used for external context.
*
* @return Wrapping Context to use for rendering
*/
static already_AddRefed<GLContext>
CreateWrappingExisting(void* aContext, void* aSurface);
#if defined(MOZ_WIDGET_ANDROID)
static EGLSurface CreateEGLSurface(void* aWindow, EGLConfig aConfig = nullptr);
static void DestroyEGLSurface(EGLSurface surface);
#endif // defined(MOZ_WIDGET_ANDROID)
/**
* Get a pointer to the global context, creating it if it doesn't exist.
*/
static GLContext*
GetGlobalContext();
/**
* Free any resources held by this Context Provider.
*/
static void
Shutdown();
};