src/gpu/GrRenderTargetOpList.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 GrRenderTargetOpList_DEFINED
#define GrRenderTargetOpList_DEFINED

#include "GrAppliedClip.h"
#include "GrOpList.h"
#include "GrPathRendering.h"
#include "GrPrimitiveProcessor.h"
#include "SkArenaAlloc.h"
#include "SkClipStack.h"
#include "SkMatrix.h"
#include "SkStringUtils.h"
#include "SkStrokeRec.h"
#include "SkTArray.h"
#include "SkTLazy.h"
#include "SkTypes.h"

class GrAuditTrail;
class GrClearOp;
class GrCaps;
class GrOp;
class GrPipelineBuilder;
class GrRenderTargetProxy;

class GrRenderTargetOpList final : public GrOpList {
private:
    using DstTexture = GrXferProcessor::DstTexture;

public:
    /** Options for GrRenderTargetOpList behavior. */
    struct Options {
        int fMaxOpCombineLookback = -1;
        int fMaxOpCombineLookahead = -1;
    };

    GrRenderTargetOpList(GrRenderTargetProxy*, GrGpu*, GrResourceProvider*,
                         GrAuditTrail*, const Options&);

    ~GrRenderTargetOpList() override;

    void makeClosed() override {
        INHERITED::makeClosed();

        fLastFullClearOp = nullptr;
        this->forwardCombine();
    }

    /**
     * Empties the draw buffer of any queued up draws.
     */
    void reset() override;

    void abandonGpuResources() override;
    void freeGpuResources() override;

    /**
     * Together these two functions flush all queued up draws to GrCommandBuffer. The return value
     * of executeOps() indicates whether any commands were actually issued to the GPU.
     */
    void prepareOps(GrOpFlushState* flushState) override;
    bool executeOps(GrOpFlushState* flushState) override;

    /**
     * Gets the capabilities of the draw target.
     */
    const GrCaps* caps() const { return fGpu->caps(); }

    uint32_t addOp(std::unique_ptr<GrOp> op, GrRenderTargetContext* renderTargetContext) {
        this->recordOp(std::move(op), renderTargetContext, nullptr, nullptr);
        return this->uniqueID();
    }
    uint32_t addOp(std::unique_ptr<GrOp> op, GrRenderTargetContext* renderTargetContext,
                   GrAppliedClip&& clip, const DstTexture& dstTexture) {
        this->recordOp(std::move(op), renderTargetContext, clip.doesClip() ? &clip : nullptr,
                       &dstTexture);
        return this->uniqueID();
    }

    /** Clears the entire render target */
    void fullClear(GrRenderTargetContext*, GrColor color);

    /** Discards the contents render target. */
    void discard(GrRenderTargetContext*);

    /**
     * Copies a pixel rectangle from one surface to another. This call may finalize
     * reserved vertex/index data (as though a draw call was made). The src pixels
     * copied are specified by srcRect. They are copied to a rect of the same
     * size in dst with top left at dstPoint. If the src rect is clipped by the
     * src bounds then  pixel values in the dst rect corresponding to area clipped
     * by the src rect are not overwritten. This method is not guaranteed to succeed
     * depending on the type of surface, configs, etc, and the backend-specific
     * limitations.
     */
    bool copySurface(GrSurface* dst,
                     GrSurface* src,
                     const SkIRect& srcRect,
                     const SkIPoint& dstPoint);

    gr_instanced::InstancedRendering* instancedRendering() const {
        SkASSERT(fInstancedRendering);
        return fInstancedRendering.get();
    }

    GrRenderTargetOpList* asRenderTargetOpList() override { return this; }

    SkDEBUGCODE(void dump() const override;)

    SkDEBUGCODE(void validateTargetsSingleRenderTarget() const;)

private:
    friend class GrRenderTargetContextPriv; // for clearStencilClip and stencil clip state.

    struct RecordedOp {
        RecordedOp(std::unique_ptr<GrOp> op, GrRenderTarget* rt, const GrAppliedClip* appliedClip,
                   const DstTexture* dstTexture)
                : fOp(std::move(op)), fRenderTarget(rt), fAppliedClip(appliedClip) {
            if (dstTexture) {
                fDstTexture = *dstTexture;
            }
        }
        std::unique_ptr<GrOp> fOp;
        // TODO: These ops will all to target the same render target and this won't be needed.
        GrPendingIOResource<GrRenderTarget, kWrite_GrIOType> fRenderTarget;
        DstTexture fDstTexture;
        const GrAppliedClip* fAppliedClip;
    };

    // If the input op is combined with an earlier op, this returns the combined op. Otherwise, it
    // returns the input op.
    GrOp* recordOp(std::unique_ptr<GrOp>, GrRenderTargetContext*, GrAppliedClip* = nullptr,
                   const DstTexture* = nullptr);

    void forwardCombine();

    // Used only via GrRenderTargetContextPriv.
    void clearStencilClip(const GrFixedClip&, bool insideStencilMask, GrRenderTargetContext*);

    // If this returns true then b has been merged into a's op.
    bool combineIfPossible(const RecordedOp& a, GrOp* b, const GrAppliedClip* bClip,
                           const DstTexture* bDstTexture);

    GrClearOp* fLastFullClearOp = nullptr;
    GrGpuResource::UniqueID fLastFullClearRenderTargetID = GrGpuResource::UniqueID::InvalidID();

    GrGpu* fGpu;
    GrResourceProvider* fResourceProvider;

    int fMaxOpLookback;
    int fMaxOpLookahead;

    std::unique_ptr<gr_instanced::InstancedRendering> fInstancedRendering;

    int32_t fLastClipStackGenID;
    SkIRect fLastDevClipBounds;

    SkSTArray<256, RecordedOp, true> fRecordedOps;

    char fClipAllocatorStorage[4096];
    SkArenaAlloc fClipAllocator;

    typedef GrOpList INHERITED;
};

#endif