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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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
#ifndef mozilla_layers_NativeLayerMacSurfaceHandler_h
#define mozilla_layers_NativeLayerMacSurfaceHandler_h
#include "mozilla/Maybe.h"
#include "mozilla/gfx/Types.h"
#include "GLTypes.h"
#include "nsISupportsImpl.h"
#include "nsRegion.h"
namespace mozilla {
namespace gl {
class GLContext;
} // namespace gl
namespace wr {
class RenderTextureHost;
class RenderMacIOSurfaceTextureHost;
} // namespace wr
namespace layers {
class SurfacePoolHandleCA;
struct SurfaceWithInvalidRegion {
CFTypeRefPtr<IOSurfaceRef> mSurface;
gfx::IntRegion mInvalidRegion;
};
struct SurfaceWithInvalidRegionAndCheckCount {
SurfaceWithInvalidRegion mEntry;
uint32_t mCheckCount; // The number of calls to IOSurfaceIsInUse
};
// A companion to macOS-specific subclasses of NativeLayer, this class
// handles the implementation of the surface management calls. The
// expectation is that NativeLayerMacIOSurfaceHandler is composed into
// these classes, rather than be used as a superclass/.
class NativeLayerMacSurfaceHandler {
public:
NativeLayerMacSurfaceHandler(const gfx::IntSize& aSize,
SurfacePoolHandleCA* aSurfacePoolHandle);
~NativeLayerMacSurfaceHandler();
gfx::IntSize Size() { return mSize; }
// Returns the "display rect", in content coordinates, of the current front
// surface. This rect acts as an extra clip and prevents invalid content from
// getting to the screen. The display rect starts out empty before the first
// call to NextSurface*. Note the different coordinate space from the regular
// clip rect: the clip rect is "outside" the layer position, the display rect
// is "inside" the layer position (moves with the layer).
gfx::IntRect DisplayRect() { return mDisplayRect; }
void SetSurfaceIsFlipped(bool aIsFlipped) { mSurfaceIsFlipped = aIsFlipped; }
bool SurfaceIsFlipped() { return mSurfaceIsFlipped; }
// Gets the next surface for drawing from our swap chain and stores it in
// mInProgressSurface. Returns whether this was successful.
// mInProgressSurface is guaranteed to be not in use by the window server.
// After a call to NextSurface, NextSurface must not be called again until
// after NotifySurfaceReady has been called. Can be called on any thread. When
// used from multiple threads, callers need to make sure that they still only
// call NextSurface and NotifySurfaceReady alternatingly and not in any other
// order.
bool NextSurface();
// Invalidates the specified region in all surfaces that are tracked by this
// layer.
void InvalidateRegionThroughoutSwapchain(const gfx::IntRegion& aRegion);
// Invalidate aUpdateRegion and make sure that mInProgressSurface retains any
// valid content from the previous surface outside of aUpdateRegion, so that
// only aUpdateRegion needs to be drawn. If content needs to be copied,
// aCopyFn is called to do the copying.
// aCopyFn: Fn(CFTypeRefPtr<IOSurfaceRef> aValidSourceIOSurface,
// const gfx::IntRegion& aCopyRegion) -> void
template <typename F>
void HandlePartialUpdate(const gfx::IntRect& aDisplayRect,
const gfx::IntRegion& aUpdateRegion, F&& aCopyFn);
Maybe<SurfaceWithInvalidRegion> GetUnusedSurfaceAndCleanUp();
// Returns a DrawTarget. The size of the DrawTarget will be the same as the
// size of this layer. The caller should draw to that DrawTarget, then drop
// its reference to the DrawTarget, and then call NotifySurfaceReady(). It can
// limit its drawing to aUpdateRegion (which is in the DrawTarget's device
// space). After a call to NextSurface*, NextSurface* must not be called again
// until after NotifySurfaceReady has been called. Can be called on any
// thread. When used from multiple threads, callers need to make sure that
// they still only call NextSurface* and NotifySurfaceReady alternatingly and
// not in any other order. aUpdateRegion and aDisplayRect are in "content
// coordinates" and must not extend beyond the layer size. If aDisplayRect
// contains parts that were not valid before, then those parts must be updated
// (must be part of aUpdateRegion), so that the entirety of aDisplayRect is
// valid after the update. The display rect determines the parts of the
// surface that will be shown; this allows using surfaces with only
// partially-valid content, as long as none of the invalid content is included
// in the display rect.
RefPtr<gfx::DrawTarget> NextSurfaceAsDrawTarget(
const gfx::IntRect& aDisplayRect, const gfx::IntRegion& aUpdateRegion,
gfx::BackendType aBackendType);
// Returns a GLuint for a framebuffer that can be used for drawing to the
// surface. The size of the framebuffer will be the same as the size of this
// layer. If aNeedsDepth is true, the framebuffer is created with a depth
// buffer.
// The framebuffer's depth buffer (if present) may be shared with other
// framebuffers of the same size, even from entirely different NativeLayer
// objects. The caller should not assume anything about the depth buffer's
// existing contents (i.e. it should clear it at the beginning of the draw).
// Callers should draw to one layer at a time, such that there is no
// interleaved drawing to different framebuffers that could be tripped up by
// the sharing.
// The caller should draw to the framebuffer, unbind it, and then call
// NotifySurfaceReady(). It can limit its drawing to aUpdateRegion (which is
// in the framebuffer's device space, possibly "upside down" if
// SurfaceIsFlipped()).
// The framebuffer will be created in the GLContext that this layer's
// SurfacePoolHandle was created for.
// After a call to NextSurface*, NextSurface* must not be called again until
// after NotifySurfaceReady has been called. Can be called on any thread. When
// used from multiple threads, callers need to make sure that they still only
// call NextSurface and NotifySurfaceReady alternatingly and not in any other
// order.
// aUpdateRegion and aDisplayRect are in "content coordinates" and must not
// extend beyond the layer size. If aDisplayRect contains parts that were not
// valid before, then those parts must be updated (must be part of
// aUpdateRegion), so that the entirety of aDisplayRect is valid after the
// update. The display rect determines the parts of the surface that will be
// shown; this allows using surfaces with only partially-valid content, as
// long as none of the invalid content is included in the display rect.
Maybe<GLuint> NextSurfaceAsFramebuffer(const gfx::IntRect& aDisplayRect,
const gfx::IntRegion& aUpdateRegion,
bool aNeedsDepth);
// Indicates that the surface which has been returned from the most recent
// call to NextSurface* is now finished being drawn to and can be displayed on
// the screen. Resets the invalid region on the surface to the empty region.
// Returns true if the display rect has changed.
bool NotifySurfaceReady();
// If you know that this layer will likely not draw any more frames, then it's
// good to call DiscardBackbuffers in order to save memory and allow other
// layer's to pick up the released surfaces from the pool.
void DiscardBackbuffers();
Maybe<SurfaceWithInvalidRegion> FrontSurface() { return mFrontSurface; }
Maybe<SurfaceWithInvalidRegion> InProgressSurface() {
return mInProgressSurface;
}
std::vector<SurfaceWithInvalidRegionAndCheckCount> Surfaces() {
return mSurfaces;
}
protected:
friend class NativeLayerCA;
gfx::IntSize mSize;
gfx::IntRect mDisplayRect;
bool mSurfaceIsFlipped = false;
#ifdef NIGHTLY_BUILD
// Track the consistency of our caller's API usage. Layers that are drawn
// should only ever be called with NotifySurfaceReady. Layers that are
// external should only ever be called with AttachExternalImage.
bool mHasEverAttachExternalImage = false;
bool mHasEverNotifySurfaceReady = false;
#endif
// Each IOSurface is initially created inside NextSurface.
// The surface stays alive until the recycling mechanism in NextSurface
// determines it is no longer needed (because the swap chain has grown too
// long) or until DiscardBackbuffers() is called or the layer is destroyed.
// During the surface's lifetime, it will continuously move through the fields
// mInProgressSurface, mFrontSurface, and back to front through the mSurfaces
// queue:
//
// mSurfaces.front()
// ------[NextSurface()]-----> mInProgressSurface
// --[NotifySurfaceReady()]--> mFrontSurface
// --[NotifySurfaceReady()]--> mSurfaces.back() --> .... -->
// mSurfaces.front()
//
// We mark an IOSurface as "in use" as long as it is either in
// mInProgressSurface. When it is in mFrontSurface or in the mSurfaces queue,
// it is not marked as "in use" by us - but it can be "in use" by the window
// server. Consequently, IOSurfaceIsInUse on a surface from mSurfaces reflects
// whether the window server is still reading from the surface, and we can use
// this indicator to decide when to recycle the surface.
//
// Users of NativeLayerCA normally proceed in this order:
// 1. Begin a frame by calling NextSurface to get the surface.
// 2. Draw to the surface.
// 3. Mark the surface as done by calling NotifySurfaceReady.
// 4. Call NativeLayerRoot::CommitToScreen(), which calls ApplyChanges()
// during a CATransaction.
// The surface we returned from the most recent call to NextSurface, before
// the matching call to NotifySurfaceReady.
// Will only be Some() between calls to NextSurface and NotifySurfaceReady.
Maybe<SurfaceWithInvalidRegion> mInProgressSurface;
Maybe<gfx::IntRegion> mInProgressUpdateRegion;
Maybe<gfx::IntRect> mInProgressDisplayRect;
// The surface that the most recent call to NotifySurfaceReady was for.
// Will be Some() after the first call to NotifySurfaceReady, for the rest of
// the layer's life time.
Maybe<SurfaceWithInvalidRegion> mFrontSurface;
// The queue of surfaces which make up the rest of our "swap chain".
// mSurfaces.front() is the next surface we'll attempt to use.
// mSurfaces.back() is the one that was used most recently.
std::vector<SurfaceWithInvalidRegionAndCheckCount> mSurfaces;
// Non-null between calls to NextSurfaceAsDrawTarget and NotifySurfaceReady.
RefPtr<MacIOSurface> mInProgressLockedIOSurface;
RefPtr<SurfacePoolHandleCA> mSurfacePoolHandle;
};
} // namespace layers
} // namespace mozilla
#endif // mozilla_layers_NativeLayerMacSurfaceHandler_h