1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "jni.h" 18 19 #include "SkCanvas.h" 20 #include "SkPaint.h" 21 #include "unicode/utypes.h" 22 23 #include "TextLayoutCache.h" 24 25 namespace android { 26 27 #define UNICODE_NOT_A_CHAR 0xffff 28 #define UNICODE_ZWSP 0x200b 29 #define UNICODE_FIRST_LOW_SURROGATE 0xdc00 30 #define UNICODE_FIRST_HIGH_SURROGATE 0xd800 31 #define UNICODE_FIRST_PRIVATE_USE 0xe000 32 #define UNICODE_FIRST_RTL_CHAR 0x0590 33 34 /* 35 * Temporary buffer size 36 */ 37 #define CHAR_BUFFER_SIZE 80 38 39 /** 40 * Turn on for using the Cache 41 */ 42 #define USE_TEXT_LAYOUT_CACHE 1 43 44 enum { 45 kBidi_LTR = 0, 46 kBidi_RTL = 1, 47 kBidi_Default_LTR = 2, 48 kBidi_Default_RTL = 3, 49 kBidi_Force_LTR = 4, 50 kBidi_Force_RTL = 5, 51 52 kBidi_Mask = 0x7 53 }; 54 55 enum { 56 kDirection_LTR = 0, 57 kDirection_RTL = 1, 58 59 kDirection_Mask = 0x1 60 }; 61 62 class TextLayout { 63 public: 64 65 /* 66 * Draws a unidirectional run of text. 67 */ 68 static void drawTextRun(SkPaint* paint, const jchar* chars, 69 jint start, jint count, jint contextCount, 70 int dirFlags, jfloat x, jfloat y, SkCanvas* canvas); 71 72 static void getTextRunAdvances(SkPaint* paint, const jchar* chars, jint start, 73 jint count, jint contextCount, jint dirFlags, 74 jfloat* resultAdvances, jfloat* resultTotalAdvance); 75 76 static void getTextRunAdvancesICU(SkPaint* paint, const jchar* chars, jint start, 77 jint count, jint contextCount, jint dirFlags, 78 jfloat* resultAdvances, jfloat& resultTotalAdvance); 79 80 static void drawText(SkPaint* paint, const jchar* text, jsize len, 81 jint bidiFlags, jfloat x, jfloat y, SkCanvas* canvas); 82 83 static void getTextPath(SkPaint* paint, const jchar* text, jsize len, 84 jint bidiFlags, jfloat x, jfloat y, SkPath* path); 85 86 static void drawTextOnPath(SkPaint* paint, const jchar* text, jsize len, 87 int bidiFlags, jfloat hOffset, jfloat vOffset, 88 SkPath* path, SkCanvas* canvas); 89 90 static bool prepareText(SkPaint* paint, const jchar* text, jsize len, jint bidiFlags, 91 const jchar** outText, int32_t* outBytes, jchar** outBuffer); 92 93 static bool prepareRtlTextRun(const jchar* context, jsize start, jsize& count, 94 jsize contextCount, jchar* shaped); 95 96 97 private: 98 static bool needsLayout(const jchar* text, jint len, jint bidiFlags); 99 static int shapeRtlText(const jchar* context, jsize start, jsize count, jsize contextCount, 100 jchar* shaped, UErrorCode& status); 101 static jint layoutLine(const jchar* text, jint len, jint flags, int &dir, jchar* buffer, 102 UErrorCode &status); 103 static void handleText(SkPaint* paint, const jchar* text, jsize len, 104 int bidiFlags, jfloat x, jfloat y, SkCanvas* canvas, SkPath* path); 105 106 static void computeAdvancesWithICU(SkPaint* paint, const UChar* chars, 107 size_t start, size_t count, size_t contextCount, int dirFlags, 108 jfloat* outAdvances, jfloat* outTotalAdvance); 109 }; 110 } // namespace android 111