blob: 280bb913a37a1dbb140e646bd9b3c6ba5f400e20 [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 SkUnicode_DEFINED
#define SkUnicode_DEFINED
#include "include/core/SkSpan.h"
#include "include/core/SkTypes.h"
#include "src/utils/SkUTF.h"
#include <vector>
#if !defined(SKUNICODE_IMPLEMENTATION)
#define SKUNICODE_IMPLEMENTATION 0
#endif
#if !defined(SKUNICODE_API)
#if defined(SKUNICODE_DLL)
#if defined(_MSC_VER)
#if SKUNICODE_IMPLEMENTATION
#define SKUNICODE_API __declspec(dllexport)
#else
#define SKUNICODE_API __declspec(dllimport)
#endif
#else
#define SKUNICODE_API __attribute__((visibility("default")))
#endif
#else
#define SKUNICODE_API
#endif
#endif
class SKUNICODE_API SkBidiIterator {
public:
typedef int32_t Position;
typedef uint8_t Level;
struct Region {
Region(Position start, Position end, Level level)
: start(start), end(end), level(level) { }
Position start;
Position end;
Level level;
};
enum Direction {
kLTR,
kRTL,
};
virtual ~SkBidiIterator() = default;
virtual Position getLength() = 0;
virtual Level getLevelAt(Position) = 0;
static void ReorderVisual(const Level runLevels[], int levelsCount, int32_t logicalFromVisual[]);
};
class SKUNICODE_API SkBreakIterator {
public:
typedef int32_t Position;
typedef int32_t Status;
virtual ~SkBreakIterator() = default;
virtual Position first() = 0;
virtual Position current() = 0;
virtual Position next() = 0;
virtual Position preceding(Position offset) = 0;
virtual Position following(Position offset) = 0;
virtual Status status() = 0;
virtual bool isDone() = 0;
virtual bool setText(const char utftext8[], int utf8Units) = 0;
virtual bool setText(const char16_t utftext16[], int utf16Units) = 0;
};
class SKUNICODE_API SkScriptIterator {
public:
typedef uint32_t ScriptID;
virtual ~SkScriptIterator() = default;
virtual bool getScript(SkUnichar u, ScriptID* script) = 0;
};
class SKUNICODE_API SkUnicode {
public:
typedef uint32_t CombiningClass;
typedef uint32_t GeneralCategory;
enum class TextDirection {
kLTR,
kRTL,
};
typedef size_t Position;
typedef uint8_t BidiLevel;
struct BidiRegion {
BidiRegion(Position start, Position end, BidiLevel level)
: start(start), end(end), level(level) { }
Position start;
Position end;
BidiLevel level;
};
enum class LineBreakType {
kSoftLineBreak = 0,
kHardLineBreak = 100,
};
enum class BreakType {
kWords,
kGraphemes,
kLines
};
struct LineBreakBefore {
LineBreakBefore(Position pos, LineBreakType breakType)
: pos(pos), breakType(breakType) { }
Position pos;
LineBreakType breakType;
};
virtual ~SkUnicode() = default;
virtual bool isControl(SkUnichar utf8) = 0;
virtual bool isWhitespace(SkUnichar utf8) = 0;
virtual bool isSpace(SkUnichar utf8) = 0;
virtual SkString convertUtf16ToUtf8(const std::u16string& utf16) = 0;
virtual SkString toUpper(const SkString&) = 0;
// Methods used in SkShaper and SkText
virtual std::unique_ptr<SkBidiIterator> makeBidiIterator
(const uint16_t text[], int count, SkBidiIterator::Direction) = 0;
virtual std::unique_ptr<SkBidiIterator> makeBidiIterator
(const char text[], int count, SkBidiIterator::Direction) = 0;
virtual std::unique_ptr<SkBreakIterator> makeBreakIterator
(const char locale[], BreakType breakType) = 0;
virtual std::unique_ptr<SkBreakIterator> makeBreakIterator(BreakType type) = 0;
virtual std::unique_ptr<SkScriptIterator> makeScriptIterator() = 0;
// High level methods (that we actually use somewhere=SkParagraph)
virtual bool getBidiRegions
(const char utf8[], int utf8Units, TextDirection dir, std::vector<BidiRegion>* results) = 0;
virtual bool getLineBreaks
(const char utf8[], int utf8Units, std::vector<LineBreakBefore>* results) = 0;
virtual bool getWords
(const char utf8[], int utf8Units, std::vector<Position>* results) = 0;
virtual bool getGraphemes
(const char utf8[], int utf8Units, std::vector<Position>* results) = 0;
template <typename Callback>
void forEachCodepoint(const char* utf8, int32_t utf8Units, Callback&& callback) {
const char* current = utf8;
const char* end = utf8 + utf8Units;
while (current < end) {
auto before = current - utf8;
SkUnichar unichar = SkUTF::NextUTF8(&current, end);
if (unichar < 0) unichar = 0xFFFD;
auto after = current - utf8;
callback(unichar, before, after);
}
}
template <typename Callback>
void forEachCodepoint(const char16_t* utf16, int32_t utf16Units, Callback&& callback) {
const char16_t* current = utf16;
const char16_t* end = utf16 + utf16Units;
while (current < end) {
auto before = current - utf16;
SkUnichar unichar = SkUTF::NextUTF16((const uint16_t**)&current, (const uint16_t*)end);
auto after = current - utf16;
callback(unichar, before, after);
}
}
template <typename Callback>
void forEachBidiRegion(const uint16_t utf16[], int utf16Units, SkBidiIterator::Direction dir, Callback&& callback) {
auto iter = makeBidiIterator(utf16, utf16Units, dir);
const uint16_t* start16 = utf16;
const uint16_t* end16 = utf16 + utf16Units;
SkBidiIterator::Level currentLevel = 0;
SkBidiIterator::Position pos16 = 0;
while (pos16 <= iter->getLength()) {
auto level = iter->getLevelAt(pos16);
if (pos16 == 0) {
currentLevel = level;
} else if (level != currentLevel) {
callback(pos16, start16 - utf16, currentLevel);
currentLevel = level;
}
if (start16 == end16) {
break;
}
SkUnichar u = SkUTF::NextUTF16(&start16, end16);
pos16 += SkUTF::ToUTF16(u);
}
}
template <typename Callback>
void forEachBreak(const char16_t utf16[], int utf16Units, SkUnicode::BreakType type, Callback&& callback) {
auto iter = makeBreakIterator(type);
iter->setText(utf16, utf16Units);
auto pos = iter->first();
do {
callback(pos, iter->status());
pos = iter->next();
} while (!iter->isDone());
}
virtual void reorderVisual(const BidiLevel runLevels[], int levelsCount, int32_t logicalFromVisual[]) = 0;
static std::unique_ptr<SkUnicode> Make();
};
#endif // SkUnicode_DEFINED