mirror of
https://github.com/flutter/flutter.git
synced 2026-02-20 02:29:02 +08:00
6b1c227da6
Before this patch, the font fallback chain iterated all installed font families if a variation selector was specified. This CL narrows down the range of iteration. To decide the font family for the variation sequence, we need to search for both the variation sequence and its base code point. The new range of the iteration is a union of them. With this change, the running time of Paint.hasGlyph for the variation sequence improves 50% and the running time of Paint.measureText for the variation sequence improves 40% for the large text case on Nexus 6 userdebug. Bug: 26784699 Bug: 11750374 Change-Id: Iced1349e3ca750821d8882c551551f65bb569794
102 lines
3.2 KiB
C++
102 lines
3.2 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;
|
|
|
|
// Returns true if there is a glyph for the code point and variation selector pair.
|
|
// Returns false if no fonts have a glyph for the code point and variation
|
|
// selector pair, or invalid variation selector is passed.
|
|
bool hasVariationSelector(uint32_t baseCodepoint, uint32_t variationSelector) 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, uint32_t vs, uint32_t langListId, int variant) const;
|
|
|
|
uint32_t calcFamilyScore(uint32_t ch, uint32_t vs, int variant, uint32_t langListId,
|
|
FontFamily* fontFamily) const;
|
|
|
|
uint32_t calcCoverageScore(uint32_t ch, uint32_t vs, FontFamily* fontFamily) const;
|
|
|
|
static uint32_t calcLanguageMatchingScore(uint32_t userLangListId,
|
|
const FontFamily& fontFamily);
|
|
|
|
static uint32_t calcVariantMatchingScore(int variant, const FontFamily& fontFamily);
|
|
|
|
// 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;
|
|
|
|
// This vector has pointers to the font family instance which has cmap 14 subtable.
|
|
std::vector<FontFamily*> mVSFamilyVec;
|
|
|
|
// These are offsets into mInstanceVec, one range per page
|
|
std::vector<Range> mRanges;
|
|
};
|
|
|
|
} // namespace android
|
|
|
|
#endif // MINIKIN_FONT_COLLECTION_H
|