cc/CCProxy.h

// Copyright 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CCProxy_h
#define CCProxy_h

#include "IntRect.h"
#include <public/WebCompositorOutputSurface.h>
#include <wtf/Noncopyable.h>
#include <wtf/PassOwnPtr.h>
#include <wtf/PassRefPtr.h>

namespace cc {

class CCThread;
struct CCRenderingStats;
struct RendererCapabilities;

// Abstract class responsible for proxying commands from the main-thread side of
// the compositor over to the compositor implementation.
class CCProxy {
    WTF_MAKE_NONCOPYABLE(CCProxy);
public:
    static void setMainThread(CCThread*);
    static CCThread* mainThread();

    static bool hasImplThread();
    static void setImplThread(CCThread*);
    static CCThread* implThread();

    // Returns 0 if the current thread is neither the main thread nor the impl thread.
    static CCThread* currentThread();

    virtual ~CCProxy();

    virtual bool compositeAndReadback(void *pixels, const IntRect&) = 0;

    virtual void startPageScaleAnimation(const IntSize& targetPosition, bool useAnchor, float scale, double durationSec) = 0;

    virtual void finishAllRendering() = 0;

    virtual bool isStarted() const = 0;

    // Attempts to initialize a context to use for rendering. Returns false if the context could not be created.
    // The context will not be used and no frames may be produced until initializeRenderer() is called.
    virtual bool initializeContext() = 0;

    // Indicates that the compositing surface associated with our context is ready to use.
    virtual void setSurfaceReady() = 0;

    virtual void setVisible(bool) = 0;

    // Attempts to initialize the layer renderer. Returns false if the context isn't usable for compositing.
    virtual bool initializeRenderer() = 0;

    // Attempts to recreate the context and layer renderer after a context lost. Returns false if the renderer couldn't be
    // reinitialized.
    virtual bool recreateContext() = 0;

    virtual void implSideRenderingStats(CCRenderingStats&) = 0;

    virtual const RendererCapabilities& rendererCapabilities() const = 0;

    virtual void setNeedsAnimate() = 0;
    virtual void setNeedsCommit() = 0;
    virtual void setNeedsRedraw() = 0;

    virtual void didAddAnimation() = 0;

    virtual bool commitRequested() const = 0;

    virtual void start() = 0; // Must be called before using the proxy.
    virtual void stop() = 0; // Must be called before deleting the proxy.

    // Forces 3D commands on all contexts to wait for all previous SwapBuffers to finish before executing in the GPU
    // process.
    virtual void forceSerializeOnSwapBuffers() = 0;

    // Maximum number of sub-region texture updates supported for each commit.
    virtual size_t maxPartialTextureUpdates() const = 0;

    virtual void acquireLayerTextures() = 0;

    // Debug hooks
#ifndef NDEBUG
    static bool isMainThread();
    static bool isImplThread();
    static bool isMainThreadBlocked();
    static void setMainThreadBlocked(bool);
#endif

    // Testing hooks
    virtual void loseContext() = 0;

#ifndef NDEBUG
    static void setCurrentThreadIsImplThread(bool);
#endif

protected:
    CCProxy();
    friend class DebugScopedSetImplThread;
    friend class DebugScopedSetMainThreadBlocked;
};

class DebugScopedSetMainThreadBlocked {
public:
    DebugScopedSetMainThreadBlocked()
    {
#if !ASSERT_DISABLED
        ASSERT(!CCProxy::isMainThreadBlocked());
        CCProxy::setMainThreadBlocked(true);
#endif
    }
    ~DebugScopedSetMainThreadBlocked()
    {
#if !ASSERT_DISABLED
        ASSERT(CCProxy::isMainThreadBlocked());
        CCProxy::setMainThreadBlocked(false);
#endif
    }
};

}

#endif