skia2/include/gpu/GrSamplerState.h
2012-09-18 14:14:49 +00:00

107 lines
3.0 KiB
C++

/*
* 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 GrSamplerState_DEFINED
#define GrSamplerState_DEFINED
#include "GrCustomStage.h"
#include "GrMatrix.h"
#include "GrTypes.h"
#include "SkShader.h"
class GrSamplerState {
public:
static const bool kBilerpDefault = false;
static const SkShader::TileMode kTileModeDefault = SkShader::kClamp_TileMode;
/**
* Default sampler state is set to clamp, use normal sampling mode, be
* unfiltered, and use identity matrix.
*/
GrSamplerState()
: fCustomStage (NULL) {
memset(this, 0, sizeof(GrSamplerState));
this->reset();
}
~GrSamplerState() {
GrSafeUnref(fCustomStage);
}
bool operator ==(const GrSamplerState& s) const {
/* We must be bit-identical as far as the CustomStage;
there may be multiple CustomStages that will produce
the same shader code and so are equivalent.
Can't take the address of fWrapX because it's :8 */
int bitwiseRegion = (intptr_t) &fCustomStage - (intptr_t) this;
GrAssert(sizeof(GrSamplerState) ==
bitwiseRegion + sizeof(fCustomStage));
return !memcmp(this, &s, bitwiseRegion) &&
((fCustomStage == s.fCustomStage) ||
(fCustomStage && s.fCustomStage &&
(fCustomStage->getFactory() ==
s.fCustomStage->getFactory()) &&
fCustomStage->isEqual(*s.fCustomStage)));
}
bool operator !=(const GrSamplerState& s) const { return !(*this == s); }
GrSamplerState& operator =(const GrSamplerState& s) {
fMatrix = s.fMatrix;
GrSafeAssign(fCustomStage, s.fCustomStage);
return *this;
}
const GrMatrix& getMatrix() const { return fMatrix; }
/**
* Access the sampler's matrix. See SampleMode for explanation of
* relationship between the matrix and sample mode.
*/
GrMatrix* matrix() { return &fMatrix; }
/**
* Multiplies the current sampler matrix a matrix
*
* After this call M' = M*m where M is the old matrix, m is the parameter
* to this function, and M' is the new matrix. (We consider points to
* be column vectors so tex cood vector t is transformed by matrix X as
* t' = X*t.)
*
* @param matrix the matrix used to modify the matrix.
*/
void preConcatMatrix(const GrMatrix& matrix) { fMatrix.preConcat(matrix); }
void reset(const GrMatrix& matrix) {
fMatrix = matrix;
GrSafeSetNull(fCustomStage);
}
void reset() {
fMatrix.reset();
GrSafeSetNull(fCustomStage);
}
GrCustomStage* setCustomStage(GrCustomStage* stage) {
GrSafeAssign(fCustomStage, stage);
return stage;
}
const GrCustomStage* getCustomStage() const { return fCustomStage; }
private:
GrMatrix fMatrix;
GrCustomStage* fCustomStage;
};
#endif