blob: d546a76136dfb4ff794a47c1b4703e92b62f24f3 [file] [log] [blame]
/*
* Copyright 2012 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef GrClipMaskManager_DEFINED
#define GrClipMaskManager_DEFINED
#include "GrPipelineBuilder.h"
#include "GrReducedClip.h"
#include "GrTexture.h"
#include "SkClipStack.h"
#include "SkDeque.h"
#include "SkPath.h"
#include "SkRefCnt.h"
#include "SkTLList.h"
#include "SkTypes.h"
class GrAppliedClip;
class GrClipStackClip;
class GrDrawTarget;
class GrPathRenderer;
class GrPathRendererChain;
class GrResourceProvider;
class GrTexture;
class SkPath;
/**
* The clip mask creator handles the generation of the clip mask. If anti
* aliasing is requested it will (in the future) generate a single channel
* (8bit) mask. If no anti aliasing is requested it will generate a 1-bit
* mask in the stencil buffer. In the non anti-aliasing case, if the clip
* mask can be represented as a rectangle then scissoring is used. In all
* cases scissoring is used to bound the range of the clip mask.
*/
class GrClipMaskManager : SkNoncopyable {
public:
GrClipMaskManager(GrDrawTarget* owner) : fDrawTarget(owner) {}
/**
* Creates a clip mask if necessary as a stencil buffer or alpha texture
* and sets the GrGpu's scissor and stencil state. If the return is false
* then the draw can be skipped. devBounds is optional but can help optimize
* clipping.
*/
bool setupClipping(const GrPipelineBuilder&, const GrClipStackClip&, const SkRect* devBounds,
GrAppliedClip*);
private:
inline GrContext* getContext();
inline const GrCaps* caps() const;
inline GrResourceProvider* resourceProvider();
static bool PathNeedsSWRenderer(GrContext* context,
bool hasUserStencilSettings,
const GrRenderTarget* rt,
const SkMatrix& viewMatrix,
const SkClipStack::Element* element,
GrPathRenderer** prOut,
bool needsStencil);
static GrPathRenderer* GetPathRenderer(GrContext* context,
GrTexture* texture,
const SkMatrix& viewMatrix,
const SkClipStack::Element* element);
// Attempts to install a series of coverage effects to implement the clip. Return indicates
// whether the element list was successfully converted to processors. *fp may be nullptr even
// when the function succeeds because all the elements were ignored. TODO: Make clip reduction
// bounds-aware and stop checking bounds in this function. Similarly, we shouldn't need to pass
// abortIfAA, but we don't yet know if all the AA elements will be eliminated.
bool getAnalyticClipProcessor(const GrReducedClip::ElementList&,
bool abortIfAA,
SkVector& clipOffset,
const SkRect* devBounds,
sk_sp<const GrFragmentProcessor>* fp);
// Draws the clip into the stencil buffer
bool createStencilClipMask(GrRenderTarget*,
int32_t elementsGenID,
GrReducedClip::InitialState initialState,
const GrReducedClip::ElementList& elements,
const SkIRect& clipSpaceIBounds,
const SkIPoint& clipSpaceToStencilOffset);
// Creates an alpha mask of the clip. The mask is a rasterization of elements through the
// rect specified by clipSpaceIBounds.
static sk_sp<GrTexture> CreateAlphaClipMask(GrContext*,
int32_t elementsGenID,
GrReducedClip::InitialState initialState,
const GrReducedClip::ElementList& elements,
const SkVector& clipToMaskOffset,
const SkIRect& clipSpaceIBounds);
// Similar to createAlphaClipMask but it rasterizes in SW and uploads to the result texture.
static sk_sp<GrTexture> CreateSoftwareClipMask(GrContext*,
int32_t elementsGenID,
GrReducedClip::InitialState initialState,
const GrReducedClip::ElementList& elements,
const SkVector& clipToMaskOffset,
const SkIRect& clipSpaceIBounds);
static bool UseSWOnlyPath(GrContext*,
const GrPipelineBuilder&,
const GrRenderTarget* rt,
const SkVector& clipToMaskOffset,
const GrReducedClip::ElementList& elements);
GrTexture* createCachedMask(int width, int height, const GrUniqueKey& key, bool renderTarget);
static const int kMaxAnalyticElements = 4;
GrDrawTarget* fDrawTarget; // This is our owning draw target.
typedef SkNoncopyable INHERITED;
};
#endif // GrClipMaskManager_DEFINED