flutter_flutter/include/minikin/FontCollection.h
Raph Levien 253320d25f Move coverage bitmap from FontCollection to FontFamily
This will significantly reduce memory usage and also speed the creation
of new font families. In particular, the coverage bitmaps for the fonts
in the fallback stack will be computed once in the Zygote, rather than
separately in each app process.

Bug: 17756900
Change-Id: I66f5706bddd4658d78fe5b709f7251ca9d2ff4f8
2014-10-29 12:34:50 -07:00

83 lines
2.3 KiB
C++

/*
* Copyright (C) 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef MINIKIN_FONT_COLLECTION_H
#define MINIKIN_FONT_COLLECTION_H
#include <vector>
#include <minikin/MinikinRefCounted.h>
#include <minikin/MinikinFont.h>
#include <minikin/FontFamily.h>
namespace android {
class FontCollection : public MinikinRefCounted {
public:
explicit FontCollection(const std::vector<FontFamily*>& typefaces);
~FontCollection();
struct Run {
FakedFont fakedFont;
int start;
int end;
};
void itemize(const uint16_t *string, size_t string_length, FontStyle style,
std::vector<Run>* result) const;
// Get the base font for the given style, useful for font-wide metrics.
MinikinFont* baseFont(FontStyle style);
// Get base font with fakery information (fake bold could affect metrics)
FakedFont baseFontFaked(FontStyle style);
uint32_t getId() const;
private:
static const int kLogCharsPerPage = 8;
static const int kPageMask = (1 << kLogCharsPerPage) - 1;
struct Range {
size_t start;
size_t end;
};
FontFamily* getFamilyForChar(uint32_t ch, FontLanguage lang, int variant) const;
// static for allocating unique id's
static uint32_t sNextId;
// unique id for this font collection (suitable for cache key)
uint32_t mId;
// Highest UTF-32 code point that can be mapped
uint32_t mMaxChar;
// This vector has ownership of the bitsets and typeface objects.
std::vector<FontFamily*> mFamilies;
// This vector contains pointers into mInstances
std::vector<FontFamily*> mFamilyVec;
// These are offsets into mInstanceVec, one range per page
std::vector<Range> mRanges;
};
} // namespace android
#endif // MINIKIN_FONT_COLLECTION_H