1 /* 2 * Copyright (C) 2013 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 package com.android.inputmethod.latin.utils; 18 19 import android.graphics.Paint; 20 import android.graphics.Rect; 21 import android.graphics.Typeface; 22 import android.util.SparseArray; 23 24 public final class TypefaceUtils { 25 private TypefaceUtils() { 26 // This utility class is not publicly instantiable. 27 } 28 29 // This sparse array caches key label text height in pixel indexed by key label text size. 30 private static final SparseArray<Float> sTextHeightCache = CollectionUtils.newSparseArray(); 31 // Working variable for the following method. 32 private static final Rect sTextHeightBounds = new Rect(); 33 34 public static float getCharHeight(final char[] referenceChar, final Paint paint) { 35 final int key = getCharGeometryCacheKey(referenceChar[0], paint); 36 synchronized (sTextHeightCache) { 37 final Float cachedValue = sTextHeightCache.get(key); 38 if (cachedValue != null) { 39 return cachedValue; 40 } 41 42 paint.getTextBounds(referenceChar, 0, 1, sTextHeightBounds); 43 final float height = sTextHeightBounds.height(); 44 sTextHeightCache.put(key, height); 45 return height; 46 } 47 } 48 49 // This sparse array caches key label text width in pixel indexed by key label text size. 50 private static final SparseArray<Float> sTextWidthCache = CollectionUtils.newSparseArray(); 51 // Working variable for the following method. 52 private static final Rect sTextWidthBounds = new Rect(); 53 54 public static float getCharWidth(final char[] referenceChar, final Paint paint) { 55 final int key = getCharGeometryCacheKey(referenceChar[0], paint); 56 synchronized (sTextWidthCache) { 57 final Float cachedValue = sTextWidthCache.get(key); 58 if (cachedValue != null) { 59 return cachedValue; 60 } 61 62 paint.getTextBounds(referenceChar, 0, 1, sTextWidthBounds); 63 final float width = sTextWidthBounds.width(); 64 sTextWidthCache.put(key, width); 65 return width; 66 } 67 } 68 69 public static float getStringWidth(final String string, final Paint paint) { 70 paint.getTextBounds(string, 0, string.length(), sTextWidthBounds); 71 return sTextWidthBounds.width(); 72 } 73 74 private static int getCharGeometryCacheKey(final char referenceChar, final Paint paint) { 75 final int labelSize = (int)paint.getTextSize(); 76 final Typeface face = paint.getTypeface(); 77 final int codePointOffset = referenceChar << 15; 78 if (face == Typeface.DEFAULT) { 79 return codePointOffset + labelSize; 80 } else if (face == Typeface.DEFAULT_BOLD) { 81 return codePointOffset + labelSize + 0x1000; 82 } else if (face == Typeface.MONOSPACE) { 83 return codePointOffset + labelSize + 0x2000; 84 } else { 85 return codePointOffset + labelSize; 86 } 87 } 88 89 public static float getLabelWidth(final String label, final Paint paint) { 90 final Rect textBounds = new Rect(); 91 paint.getTextBounds(label, 0, label.length(), textBounds); 92 return textBounds.width(); 93 } 94 } 95
