blob: 2aaaa0474fe39d399ade665898d9ccefa2d1d3b2 [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.
*/
#include "GrPrimitiveProcessor.h"
#include "GrCoordTransform.h"
/**
* The key for an individual coord transform is made up of a matrix type, a precision, and a bit
* that indicates the source of the input coords.
*/
enum {
kMatrixTypeKeyBits = 1,
kMatrixTypeKeyMask = (1 << kMatrixTypeKeyBits) - 1,
kPrecisionBits = 2,
kPrecisionShift = kMatrixTypeKeyBits,
kPositionCoords_Flag = (1 << (kPrecisionShift + kPrecisionBits)),
kTransformKeyBits = kMatrixTypeKeyBits + kPrecisionBits + 2,
};
GR_STATIC_ASSERT(kHigh_GrSLPrecision < (1 << kPrecisionBits));
/**
* We specialize the vertex code for each of these matrix types.
*/
enum MatrixType {
kNoPersp_MatrixType = 0,
kGeneral_MatrixType = 1,
};
uint32_t
GrPrimitiveProcessor::getTransformKey(const SkTArray<const GrCoordTransform*, true>& coords,
int numCoords) const {
uint32_t totalKey = 0;
for (int t = 0; t < numCoords; ++t) {
uint32_t key = 0;
const GrCoordTransform* coordTransform = coords[t];
if (coordTransform->getMatrix().hasPerspective()) {
key |= kGeneral_MatrixType;
} else {
key |= kNoPersp_MatrixType;
}
if (!this->hasExplicitLocalCoords()) {
key |= kPositionCoords_Flag;
}
GR_STATIC_ASSERT(kGrSLPrecisionCount <= (1 << kPrecisionBits));
key |= (coordTransform->precision() << kPrecisionShift);
key <<= kTransformKeyBits * t;
SkASSERT(0 == (totalKey & key)); // keys for each transform ought not to overlap
totalKey |= key;
}
return totalKey;
}