blob: 5cf35690723a8bf827f0da7b20923ae9bf568262 [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 "GrReducedClip.h"
#include "SkClipStack.h"
#include "SkTypes.h"
class GrAppliedClip;
class GrClipStackClip;
class GrContext;
class GrDrawContext;
class GrPathRenderer;
class GrTexture;
class GrTextureProvider;
class GrUniqueKey;
/**
* 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.
*/
// This has to remain a class, for now, so it can be friended (by GrDrawContext & GrContext)
class GrClipMaskManager {
public:
/**
* 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.
*/
static bool SetupClipping(GrContext*,
GrDrawContext*,
const GrClipStackClip&,
const SkRect* devBounds,
bool useHWAA,
bool hasUserStencilSettings,
GrAppliedClip* out);
private:
static bool PathNeedsSWRenderer(GrContext* context,
bool hasUserStencilSettings,
const GrDrawContext*,
const SkMatrix& viewMatrix,
const SkClipStack::Element* element,
GrPathRenderer** prOut,
bool needsStencil);
// Draws the clip into the stencil buffer
static bool CreateStencilClipMask(GrContext*,
GrDrawContext*,
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(GrTextureProvider*,
int32_t elementsGenID,
GrReducedClip::InitialState initialState,
const GrReducedClip::ElementList& elements,
const SkVector& clipToMaskOffset,
const SkIRect& clipSpaceIBounds);
static bool UseSWOnlyPath(GrContext*,
bool hasUserStencilSettings,
const GrDrawContext*,
const SkVector& clipToMaskOffset,
const GrReducedClip::ElementList& elements);
static GrTexture* CreateCachedMask(int width, int height, const GrUniqueKey& key,
bool renderTarget);
};
#endif // GrClipMaskManager_DEFINED