blob: ad6ed545d9d58b6b8decac26a1005790ddb4d2f4 [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 SkFontMgr_DEFINED
#define SkFontMgr_DEFINED
#include "SkFontStyle.h"
#include "SkRefCnt.h"
#include "SkScalar.h"
#include "SkTypes.h"
class SkData;
class SkFontData;
class SkStreamAsset;
class SkString;
class SkTypeface;
class SK_API SkFontStyleSet : public SkRefCnt {
public:
virtual int count() = 0;
virtual void getStyle(int index, SkFontStyle*, SkString* style) = 0;
virtual SkTypeface* createTypeface(int index) = 0;
virtual SkTypeface* matchStyle(const SkFontStyle& pattern) = 0;
static SkFontStyleSet* CreateEmpty();
protected:
SkTypeface* matchStyleCSS3(const SkFontStyle& pattern);
private:
typedef SkRefCnt INHERITED;
};
class SK_API SkFontMgr : public SkRefCnt {
public:
int countFamilies() const;
void getFamilyName(int index, SkString* familyName) const;
SkFontStyleSet* createStyleSet(int index) const;
/**
* The caller must call unref() on the returned object.
* Never returns NULL; will return an empty set if the name is not found.
*
* Passing |nullptr| as the parameter will return the default system font.
*
* It is possible that this will return a style set not accessible from
* createStyleSet(int) due to hidden or auto-activated fonts.
*/
SkFontStyleSet* matchFamily(const char familyName[]) const;
/**
* Find the closest matching typeface to the specified familyName and style
* and return a ref to it. The caller must call unref() on the returned
* object. Will never return NULL, as it will return the default font if
* no matching font is found.
*
* Passing |nullptr| as the parameter for |familyName| will return the
* default system font.
*
* It is possible that this will return a style set not accessible from
* createStyleSet(int) or matchFamily(const char[]) due to hidden or
* auto-activated fonts.
*/
SkTypeface* matchFamilyStyle(const char familyName[], const SkFontStyle&) const;
/**
* Use the system fallback to find a typeface for the given character.
* Note that bcp47 is a combination of ISO 639, 15924, and 3166-1 codes,
* so it is fine to just pass a ISO 639 here.
*
* Will return NULL if no family can be found for the character
* in the system fallback.
*
* Passing |nullptr| as the parameter for |familyName| will return the
* default system font.
*
* bcp47[0] is the least significant fallback, bcp47[bcp47Count-1] is the
* most significant. If no specified bcp47 codes match, any font with the
* requested character will be matched.
*/
SkTypeface* matchFamilyStyleCharacter(const char familyName[], const SkFontStyle&,
const char* bcp47[], int bcp47Count,
SkUnichar character) const;
SkTypeface* matchFaceStyle(const SkTypeface*, const SkFontStyle&) const;
/**
* Create a typeface for the specified data and TTC index (pass 0 for none)
* or NULL if the data is not recognized. The caller must call unref() on
* the returned object if it is not null.
*/
SkTypeface* createFromData(SkData*, int ttcIndex = 0) const;
/**
* Create a typeface for the specified stream and TTC index
* (pass 0 for none) or NULL if the stream is not recognized. The caller
* must call unref() on the returned object if it is not null.
*/
SkTypeface* createFromStream(SkStreamAsset*, int ttcIndex = 0) const;
struct FontParameters {
struct Axis {
SkFourByteTag fTag;
SkScalar fStyleValue;
};
FontParameters() : fCollectionIndex(0), fAxisCount(0), fAxes(nullptr) {}
/** 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.
*/
FontParameters& setCollectionIndex(int collectionIndex) {
fCollectionIndex = collectionIndex;
return *this;
}
/** Specify the GX variation axis values.
*
* Any axes not specified will use the default value. Specified axes not present in the
* font will be ignored.
*
* @param axes not copied. This pointer must remain valid for life of FontParameters.
*/
FontParameters& setAxes(const Axis* axes, int axisCount) {
fAxisCount = axisCount;
fAxes = axes;
return *this;
}
int getCollectionIndex() const {
return fCollectionIndex;
}
const Axis* getAxes(int* axisCount) const {
*axisCount = fAxisCount;
return fAxes;
}
private:
int fCollectionIndex;
int fAxisCount;
const Axis* fAxes;
};
/* Experimental, API subject to change. */
SkTypeface* createFromStream(SkStreamAsset*, const FontParameters&) const;
/**
* Create a typeface from the specified font data.
* Takes ownership of the font data, so the caller should not reference it again.
* Will return NULL if the typeface could not be created.
* The caller must call unref() on the returned object if it is not null.
*/
SkTypeface* createFromFontData(SkFontData*) const;
/**
* Create a typeface for the specified fileName and TTC index
* (pass 0 for none) or NULL if the file is not found, or its contents are
* not recognized. The caller must call unref() on the returned object
* if it is not null.
*/
SkTypeface* createFromFile(const char path[], int ttcIndex = 0) const;
SkTypeface* legacyCreateTypeface(const char familyName[], SkFontStyle style) const;
/**
* Return a ref to the default fontmgr. The caller must call unref() on
* the returned object.
*/
static SkFontMgr* RefDefault();
protected:
virtual int onCountFamilies() const = 0;
virtual void onGetFamilyName(int index, SkString* familyName) const = 0;
virtual SkFontStyleSet* onCreateStyleSet(int index)const = 0;
/** May return NULL if the name is not found. */
virtual SkFontStyleSet* onMatchFamily(const char familyName[]) const = 0;
virtual SkTypeface* onMatchFamilyStyle(const char familyName[],
const SkFontStyle&) const = 0;
virtual SkTypeface* onMatchFamilyStyleCharacter(const char familyName[], const SkFontStyle&,
const char* bcp47[], int bcp47Count,
SkUnichar character) const = 0;
virtual SkTypeface* onMatchFaceStyle(const SkTypeface*,
const SkFontStyle&) const = 0;
virtual SkTypeface* onCreateFromData(SkData*, int ttcIndex) const = 0;
virtual SkTypeface* onCreateFromStream(SkStreamAsset*, int ttcIndex) const = 0;
// TODO: make pure virtual.
virtual SkTypeface* onCreateFromStream(SkStreamAsset*, const FontParameters&) const;
virtual SkTypeface* onCreateFromFontData(SkFontData*) const;
virtual SkTypeface* onCreateFromFile(const char path[], int ttcIndex) const = 0;
virtual SkTypeface* onLegacyCreateTypeface(const char familyName[], SkFontStyle) const = 0;
private:
static SkFontMgr* Factory(); // implemented by porting layer
friend SkFontMgr* sk_fontmgr_create_default();
typedef SkRefCnt INHERITED;
};
#endif