GrContext.h

/*
 * Copyright 2010 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef GrContext_DEFINED
#define GrContext_DEFINED

#include "GrCaps.h"
#include "GrClip.h"
#include "GrColor.h"
#include "GrPaint.h"
#include "GrRenderTarget.h"
#include "GrTextureProvider.h"
#include "SkMatrix.h"
#include "SkPathEffect.h"
#include "SkTypes.h"
#include "../private/GrAuditTrail.h"
#include "../private/GrSingleOwner.h"
#include "../private/SkMutex.h"

struct GrBatchAtlasConfig;
class GrBatchFontCache;
struct GrContextOptions;
class GrContextPriv;
class GrContextThreadSafeProxy;
class GrDrawingManager;
class GrDrawContext;
class GrFragmentProcessor;
class GrGpu;
class GrIndexBuffer;
class GrOvalRenderer;
class GrPath;
class GrPipelineBuilder;
class GrResourceEntry;
class GrResourceCache;
class GrResourceProvider;
class GrTestTarget;
class GrTextBlobCache;
class GrTextContext;
class GrTextureParams;
class GrVertexBuffer;
class GrSwizzle;
class SkTraceMemoryDump;

class SK_API GrContext : public SkRefCnt {
public:
    static GrContext* Create(GrBackend, GrBackendContext, const GrContextOptions& options);
    static GrContext* Create(GrBackend, GrBackendContext);

    static GrContext* CreateMockContext();

    virtual ~GrContext();

    GrContextThreadSafeProxy* threadSafeProxy();

    void resetContext(uint32_t state = kAll_GrBackendState);

    typedef void (*PFCleanUpFunc)(const GrContext* context, void* info);

    void addCleanUp(PFCleanUpFunc cleanUp, void* info) {
        CleanUpData* entry = fCleanUpData.push();

        entry->fFunc = cleanUp;
        entry->fInfo = info;
    }

    void abandonContext();

    void releaseResourcesAndAbandonContext();

    // Resource Cache

    void getResourceCacheLimits(int* maxResources, size_t* maxResourceBytes) const;

    void getResourceCacheUsage(int* resourceCount, size_t* resourceBytes) const;

    void setResourceCacheLimits(int maxResources, size_t maxResourceBytes);

    GrTextureProvider* textureProvider() { return fTextureProvider; }
    const GrTextureProvider* textureProvider() const { return fTextureProvider; }

    void freeGpuResources();

    void purgeAllUnlockedResources();

    const GrCaps* caps() const { return fCaps; }

    int getRecommendedSampleCount(GrPixelConfig config, SkScalar dpi) const;

    sk_sp<GrDrawContext> makeDrawContext(SkBackingFit fit, 
                                         int width, int height,
                                         GrPixelConfig config,
                                         sk_sp<SkColorSpace> colorSpace,
                                         int sampleCnt = 0,
                                         GrSurfaceOrigin origin = kDefault_GrSurfaceOrigin,
                                         const SkSurfaceProps* surfaceProps = nullptr,
                                         SkBudgeted = SkBudgeted::kYes);

    // Misc.

    enum FlushBits {
        kDiscard_FlushBit                    = 0x2,
    };

    void flush(int flagsBitfield = 0);

    void flushIfNecessary() {
        if (fFlushToReduceCacheSize || this->caps()->immediateFlush()) {
            this->flush();
        }
    }

    enum PixelOpsFlags {
        kDontFlush_PixelOpsFlag = 0x1,
        kFlushWrites_PixelOp = 0x2,
        kUnpremul_PixelOpsFlag  = 0x4,
    };

    bool readSurfacePixels(GrSurface* surface,
                           int left, int top, int width, int height,
                           GrPixelConfig config, void* buffer,
                           size_t rowBytes = 0,
                           uint32_t pixelOpsFlags = 0);

    bool writeSurfacePixels(GrSurface* surface,
                            int left, int top, int width, int height,
                            GrPixelConfig config, const void* buffer,
                            size_t rowBytes,
                            uint32_t pixelOpsFlags = 0);

    bool copySurface(GrSurface* dst,
                     GrSurface* src,
                     const SkIRect& srcRect,
                     const SkIPoint& dstPoint);

    bool copySurface(GrSurface* dst, GrSurface* src) {
        return this->copySurface(dst, src, SkIRect::MakeWH(dst->width(), dst->height()),
                                 SkIPoint::Make(0,0));
    }

    void flushSurfaceWrites(GrSurface* surface);

    void flushSurfaceIO(GrSurface* surface);

    void prepareSurfaceForExternalIO(GrSurface*);

    uint32_t uniqueID() { return fUniqueID; }

    // Functions intended for internal use only.
    GrGpu* getGpu() { return fGpu; }
    const GrGpu* getGpu() const { return fGpu; }
    GrBatchFontCache* getBatchFontCache() { return fBatchFontCache; }
    GrTextBlobCache* getTextBlobCache() { return fTextBlobCache; }
    bool abandoned() const;
    GrResourceProvider* resourceProvider() { return fResourceProvider; }
    const GrResourceProvider* resourceProvider() const { return fResourceProvider; }
    GrResourceCache* getResourceCache() { return fResourceCache; }

    // Called by tests that draw directly to the context via GrDrawContext
    void getTestTarget(GrTestTarget*, sk_sp<GrDrawContext>);

    void resetGpuStats() const ;

    void dumpCacheStats(SkString*) const;
    void dumpCacheStatsKeyValuePairs(SkTArray<SkString>* keys, SkTArray<double>* values) const;
    void printCacheStats() const;

    void dumpGpuStats(SkString*) const;
    void dumpGpuStatsKeyValuePairs(SkTArray<SkString>* keys, SkTArray<double>* values) const;
    void printGpuStats() const;

    void setTextBlobCacheLimit_ForTesting(size_t bytes);

    void setTextContextAtlasSizes_ForTesting(const GrBatchAtlasConfig* configs);

    void dumpMemoryStatistics(SkTraceMemoryDump* traceMemoryDump) const;

    GrTexture* getFontAtlasTexture(GrMaskFormat format);

    GrAuditTrail* getAuditTrail() { return &fAuditTrail; }

    SkDEBUGCODE(GrSingleOwner* debugSingleOwner() const { return &fSingleOwner; } )

    // Provides access to functions that aren't part of the public API.
    GrContextPriv contextPriv();
    const GrContextPriv contextPriv() const;

private:
    GrGpu*                                  fGpu;
    const GrCaps*                           fCaps;
    GrResourceCache*                        fResourceCache;
    // this union exists because the inheritance of GrTextureProvider->GrResourceProvider
    // is in a private header.
    union {
        GrResourceProvider*                 fResourceProvider;
        GrTextureProvider*                  fTextureProvider;
    };

    SkAutoTUnref<GrContextThreadSafeProxy>  fThreadSafeProxy;

    GrBatchFontCache*                       fBatchFontCache;
    SkAutoTDelete<GrTextBlobCache>          fTextBlobCache;

    // Set by OverbudgetCB() to request that GrContext flush before exiting a draw.
    bool                                    fFlushToReduceCacheSize;
    bool                                    fDidTestPMConversions;
    int                                     fPMToUPMConversion;
    int                                     fUPMToPMConversion;
    // The sw backend may call GrContext::readSurfacePixels on multiple threads
    // We may transfer the responsibilty for using a mutex to the sw backend
    // when there are fewer code paths that lead to a readSurfacePixels call
    // from the sw backend. readSurfacePixels is reentrant in one case - when performing
    // the PM conversions test. To handle this we do the PM conversions test outside
    // of fReadPixelsMutex and use a separate mutex to guard it. When it re-enters
    // readSurfacePixels it will grab fReadPixelsMutex and release it before the outer
    // readSurfacePixels proceeds to grab it.
    // TODO: Stop pretending to make GrContext thread-safe for sw rasterization and provide
    // a mechanism to make a SkPicture safe for multithreaded sw rasterization.
    SkMutex                                 fReadPixelsMutex;
    SkMutex                                 fTestPMConversionsMutex;

    // In debug builds we guard against improper thread handling
    // This guard is passed to the GrDrawingManager and, from there to all the
    // GrDrawContexts.  It is also passed to the GrTextureProvider and SkGpuDevice.
    mutable GrSingleOwner                   fSingleOwner;

    struct CleanUpData {
        PFCleanUpFunc fFunc;
        void*         fInfo;
    };

    SkTDArray<CleanUpData>                  fCleanUpData;

    const uint32_t                          fUniqueID;

    SkAutoTDelete<GrDrawingManager>         fDrawingManager;

    GrAuditTrail                            fAuditTrail;

    // TODO: have the GrClipStackClip use drawContexts and rm this friending
    friend class GrClipStackClip;  // for access to drawingManager
    friend class GrDrawingManager; // for access to drawingManager for ProgramUnitTest
    friend class GrContextPriv;

    GrDrawingManager* drawingManager() { return fDrawingManager; }

    GrContext(); // init must be called after the constructor.
    bool init(GrBackend, GrBackendContext, const GrContextOptions& options);

    void initMockContext();
    void initCommon(const GrContextOptions&);

    sk_sp<GrFragmentProcessor> createPMToUPMEffect(GrTexture*, const GrSwizzle&,
                                                   const SkMatrix&) const;
    sk_sp<GrFragmentProcessor> createUPMToPMEffect(GrTexture*, const GrSwizzle&,
                                                   const SkMatrix&) const;
    void testPMConversionsIfNecessary(uint32_t flags);
    bool didFailPMUPMConversionTest() const;

    static void OverBudgetCB(void* data);

    static void TextBlobCacheOverBudgetCB(void* data);

    typedef SkRefCnt INHERITED;
};

class GrContextThreadSafeProxy : public SkRefCnt {
private:
    GrContextThreadSafeProxy(const GrCaps* caps, uint32_t uniqueID)
        : fCaps(SkRef(caps))
        , fContextUniqueID(uniqueID) {}

    SkAutoTUnref<const GrCaps>  fCaps;
    uint32_t                    fContextUniqueID;

    friend class GrContext;
    friend class SkImage;

    typedef SkRefCnt INHERITED;
};

#endif