blob: 0a1abc10578b4b6e6b86e4aef124348c6331a032 [file] [log] [blame]
/*
* Copyright 2014 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef GrPathRendering_DEFINED
#define GrPathRendering_DEFINED
#include "SkPath.h"
#include "GrPipeline.h"
class GrGpu;
class GrPath;
class GrStencilSettings;
class GrStyle;
struct SkScalerContextEffects;
class SkDescriptor;
class SkTypeface;
/**
* Abstract class wrapping HW path rendering API.
*
* The subclasses of this class use the possible HW API to render paths (as opposed to path
* rendering implemented in Skia on top of a "3d" HW API).
* The subclasses hold the global state needed to render paths, including shadow of the global HW
* API state. Similar to GrGpu.
*
* It is expected that the lifetimes of GrGpuXX and GrXXPathRendering are the same. The call context
* interface (eg. * the concrete instance of GrGpu subclass) should be provided to the instance
* during construction.
*/
class GrPathRendering {
public:
virtual ~GrPathRendering() { }
enum PathTransformType {
kNone_PathTransformType, //!< []
kTranslateX_PathTransformType, //!< [kMTransX]
kTranslateY_PathTransformType, //!< [kMTransY]
kTranslate_PathTransformType, //!< [kMTransX, kMTransY]
kAffine_PathTransformType, //!< [kMScaleX, kMSkewX, kMTransX, kMSkewY, kMScaleY, kMTransY]
kLast_PathTransformType = kAffine_PathTransformType
};
static inline int PathTransformSize(PathTransformType type) {
switch (type) {
case kNone_PathTransformType:
return 0;
case kTranslateX_PathTransformType:
case kTranslateY_PathTransformType:
return 1;
case kTranslate_PathTransformType:
return 2;
case kAffine_PathTransformType:
return 6;
default:
SK_ABORT("Unknown path transform type");
return 0;
}
}
// No native support for inverse at this time
enum FillType {
/** Specifies that "inside" is computed by a non-zero sum of signed
edge crossings
*/
kWinding_FillType,
/** Specifies that "inside" is computed by an odd number of edge
crossings
*/
kEvenOdd_FillType,
};
static const GrUserStencilSettings& GetStencilPassSettings(FillType);
/**
* Creates a new gpu path, based on the specified path and stroke and returns it.
*
* @param SkPath the geometry.
* @param GrStyle the style applied to the path. Styles with non-dash path effects are not
* allowed.
* @return a new GPU path object.
*/
virtual sk_sp<GrPath> createPath(const SkPath&, const GrStyle&) = 0;
/** None of these params are optional, pointers used just to avoid making copies. */
struct StencilPathArgs {
StencilPathArgs(bool useHWAA,
GrRenderTargetProxy* proxy,
const SkMatrix* viewMatrix,
const GrScissorState* scissor,
const GrStencilSettings* stencil)
: fUseHWAA(useHWAA)
, fProxy(proxy)
, fViewMatrix(viewMatrix)
, fScissor(scissor)
, fStencil(stencil) {
}
bool fUseHWAA;
GrRenderTargetProxy* fProxy;
const SkMatrix* fViewMatrix;
const GrScissorState* fScissor;
const GrStencilSettings* fStencil;
};
void stencilPath(const StencilPathArgs& args, const GrPath* path);
void drawPath(const GrPipeline& pipeline,
const GrPrimitiveProcessor& primProc,
const GrStencilSettings& stencilPassSettings, // Cover pass settings in pipeline.
const GrPath* path);
protected:
GrPathRendering(GrGpu* gpu) : fGpu(gpu) { }
virtual void onStencilPath(const StencilPathArgs&, const GrPath*) = 0;
virtual void onDrawPath(const GrPipeline&,
const GrPrimitiveProcessor&,
const GrStencilSettings&,
const GrPath*) = 0;
GrGpu* fGpu;
private:
GrPathRendering& operator=(const GrPathRendering&);
};
#endif