skia2/include/core/SkFontArguments.h
Ben Wagner e346b1eea4 Add SkTypeface::getVariationDesignParameters
This adds a way for users to query the axis parameters for a typeface.

Change-Id: Idc2ac0d84bc7ae2ca484ae410cba5b01883418e5
Reviewed-on: https://skia-review.googlesource.com/137706
Commit-Queue: Ben Wagner <bungeman@google.com>
Reviewed-by: Mike Reed <reed@google.com>
2018-07-12 17:30:20 +00:00

80 lines
2.5 KiB
C++

/*
* Copyright 2017 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkFontArguments_DEFINED
#define SkFontArguments_DEFINED
#include "SkScalar.h"
#include "SkTypes.h"
/** Represents a set of actual arguments for a font. */
struct SkFontArguments {
struct VariationPosition {
struct Coordinate {
SkFourByteTag axis;
float value;
};
const Coordinate* coordinates;
int coordinateCount;
};
// deprecated, use VariationPosition::Coordinate instead
struct Axis {
SkFourByteTag fTag;
float fStyleValue;
};
SkFontArguments() : fCollectionIndex(0), fVariationDesignPosition{nullptr, 0} {}
/** Specify the index of the desired font.
*
* Font formats like ttc, dfont, cff, cid, pfr, t42, t1, and fon may actually be indexed
* collections of fonts.
*/
SkFontArguments& setCollectionIndex(int collectionIndex) {
fCollectionIndex = collectionIndex;
return *this;
}
// deprecated, use setVariationDesignPosition instead.
SkFontArguments& setAxes(const Axis* axes, int axisCount) {
fVariationDesignPosition.coordinates =
reinterpret_cast<const VariationPosition::Coordinate*>(axes);
fVariationDesignPosition.coordinateCount = axisCount;
return *this;
}
/** Specify a position in the variation design space.
*
* Any axis not specified will use the default value.
* Any specified axis not actually present in the font will be ignored.
*
* @param position not copied. The value must remain valid for life of SkFontArguments.
*/
SkFontArguments& setVariationDesignPosition(VariationPosition position) {
fVariationDesignPosition.coordinates = position.coordinates;
fVariationDesignPosition.coordinateCount = position.coordinateCount;
return *this;
}
int getCollectionIndex() const {
return fCollectionIndex;
}
// deprecated, use getVariationDesignPosition instead.
const Axis* getAxes(int* axisCount) const {
*axisCount = fVariationDesignPosition.coordinateCount;
return reinterpret_cast<const Axis*>(fVariationDesignPosition.coordinates);
}
VariationPosition getVariationDesignPosition() const {
return fVariationDesignPosition;
}
private:
int fCollectionIndex;
VariationPosition fVariationDesignPosition;
};
#endif