blob: 0d085e3ea9f1659c3413a0183e1c12996c58b7ea [file] [log] [blame]
/*
* Copyright 2020 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef sktext_gpu_SDFTControl_DEFINED
#define sktext_gpu_SDFTControl_DEFINED
#include "include/core/SkScalar.h"
#include "include/core/SkTypes.h"
#include <tuple>
class SkFont;
class SkMatrix;
class SkPaint;
class SkReadBuffer;
class SkWriteBuffer;
struct SkPoint;
namespace sktext::gpu {
#if !defined(SK_DISABLE_SDF_TEXT)
// Two numbers fMatrixMin and fMatrixMax such that if viewMatrix.getMaxScale() is between them then
// this SDFT size can be reused.
class SDFTMatrixRange {
public:
SDFTMatrixRange(SkScalar min, SkScalar max) : fMatrixMin{min}, fMatrixMax{max} {}
bool matrixInRange(const SkMatrix& matrix) const;
void flatten(SkWriteBuffer& buffer) const;
static SDFTMatrixRange MakeFromBuffer(SkReadBuffer& buffer);
private:
const SkScalar fMatrixMin,
fMatrixMax;
};
#endif
class SDFTControl {
public:
#if !defined(SK_DISABLE_SDF_TEXT)
SDFTControl(bool ableToUseSDFT, bool useSDFTForSmallText, bool useSDFTForPerspectiveText,
SkScalar min, SkScalar max);
// Produce a font, a scale factor from the nominal size to the source space size, and matrix
// range where this font can be reused.
std::tuple<SkFont, SkScalar, SDFTMatrixRange>
getSDFFont(const SkFont& font, const SkMatrix& viewMatrix, const SkPoint& textLocation) const;
bool isSDFT(SkScalar approximateDeviceTextSize, const SkPaint& paint,
const SkMatrix& matrix) const;
SkScalar maxSize() const { return fMaxDistanceFieldFontSize; }
#else
SDFTControl() {}
#endif
bool isDirect(SkScalar approximateDeviceTextSize, const SkPaint& paint,
const SkMatrix& matrix) const;
private:
#if !defined(SK_DISABLE_SDF_TEXT)
static SkScalar MinSDFTRange(bool useSDFTForSmallText, SkScalar min);
// Below this size (in device space) distance field text will not be used.
const SkScalar fMinDistanceFieldFontSize;
// Above this size (in device space) distance field text will not be used and glyphs will
// be rendered from outline as individual paths.
const SkScalar fMaxDistanceFieldFontSize;
const bool fAbleToUseSDFT;
const bool fAbleToUsePerspectiveSDFT;
#endif
};
} // namespace sktext::gpu
#endif // sktext_SDFTControl_DEFINED