blob: 5d3faa3047c1267ce733c07e67af72815deac8e9 [file] [log] [blame]
/*
* Copyright 2013 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef GrCoordTransform_DEFINED
#define GrCoordTransform_DEFINED
#include "SkMatrix.h"
#include "GrSurfaceProxyPriv.h"
#include "GrTextureProxy.h"
class GrTexture;
/**
* A class representing a linear transformation of local coordinates. GrFragnentProcessors
* these transformations, and the GrGeometryProcessor implements the transformation.
*/
class GrCoordTransform {
public:
GrCoordTransform()
: fProxy(nullptr)
, fNormalize(false)
, fReverseY(false) {
SkDEBUGCODE(fInProcessor = false);
}
GrCoordTransform(const GrCoordTransform&) = default;
/**
* Create a transformation that maps [0, 1] to a proxy's boundaries. The proxy origin also
* implies whether a y-reversal should be performed.
*/
GrCoordTransform(GrTextureProxy* proxy) {
SkASSERT(proxy);
SkDEBUGCODE(fInProcessor = false);
this->reset(SkMatrix::I(), proxy, true);
}
/**
* Create a transformation from a matrix. The proxy origin also implies whether a y-reversal
* should be performed.
*/
GrCoordTransform(const SkMatrix& m, GrTextureProxy* proxy) {
SkASSERT(proxy);
SkDEBUGCODE(fInProcessor = false);
this->reset(m, proxy, true);
}
/**
* Create a transformation that applies the matrix to a coord set.
*/
GrCoordTransform(const SkMatrix& m) {
SkDEBUGCODE(fInProcessor = false);
this->reset(m);
}
void reset(const SkMatrix& m, GrTextureProxy* proxy, bool normalize) {
SkASSERT(proxy);
SkASSERT(!fInProcessor);
fMatrix = m;
fProxy = proxy;
fNormalize = normalize;
fReverseY = kBottomLeft_GrSurfaceOrigin == proxy->origin();
}
void reset(const SkMatrix& m) {
SkASSERT(!fInProcessor);
fMatrix = m;
fProxy = nullptr;
fNormalize = false;
fReverseY = false;
}
GrCoordTransform& operator= (const GrCoordTransform& that) {
SkASSERT(!fInProcessor);
fMatrix = that.fMatrix;
fProxy = that.fProxy;
fNormalize = that.fNormalize;
fReverseY = that.fReverseY;
return *this;
}
/**
* Access the matrix for editing. Note, this must be done before adding the transform to an
* effect, since effects are immutable.
*/
SkMatrix* accessMatrix() {
SkASSERT(!fInProcessor);
return &fMatrix;
}
bool hasSameEffectAs(const GrCoordTransform& that) const {
if (fNormalize != that.fNormalize ||
fReverseY != that.fReverseY ||
!fMatrix.cheapEqualTo(that.fMatrix)) {
return false;
}
if (fNormalize) {
if (fProxy->underlyingUniqueID() != that.fProxy->underlyingUniqueID()) {
return false;
}
}
return true;
}
const SkMatrix& getMatrix() const { return fMatrix; }
const GrTextureProxy* proxy() const { return fProxy; }
bool normalize() const { return fNormalize; }
bool reverseY() const { return fReverseY; }
// This should only ever be called at flush time after the backing texture has been
// successfully instantiated
GrTexture* peekTexture() const {
SkASSERT(fProxy->priv().peekTexture());
return fProxy->priv().peekTexture();
}
private:
// The textures' effect is to optionally normalize the final matrix, so a blind
// equality check could be misleading
bool operator==(const GrCoordTransform& that) const;
bool operator!=(const GrCoordTransform& that) const;
SkMatrix fMatrix;
const GrTextureProxy* fProxy;
bool fNormalize;
bool fReverseY;
#ifdef SK_DEBUG
public:
void setInProcessor() const { fInProcessor = true; }
private:
mutable bool fInProcessor;
#endif
};
#endif