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 package android.graphics; 18 19 import com.android.layoutlib.bridge.impl.DelegateManager; 20 import com.android.tools.layoutlib.annotations.LayoutlibDelegate; 21 22 import android.graphics.PorterDuff.Mode; 23 24 import java.awt.Graphics2D; 25 import java.awt.image.BufferedImage; 26 27 import static com.android.layoutlib.bridge.impl.PorterDuffUtility.getComposite; 28 import static com.android.layoutlib.bridge.impl.PorterDuffUtility.getPorterDuffMode; 29 30 /** 31 * Delegate implementing the native methods of android.graphics.PorterDuffColorFilter 32 * 33 * Through the layoutlib_create tool, the original native methods of PorterDuffColorFilter have 34 * been replaced by calls to methods of the same name in this delegate class. 35 * 36 * This class behaves like the original native implementation, but in Java, keeping previously 37 * native data into its own objects and mapping them to int that are sent back and forth between 38 * it and the original PorterDuffColorFilter class. 39 * 40 * Because this extends {@link ColorFilter_Delegate}, there's no need to use a 41 * {@link DelegateManager}, as all the Shader classes will be added to the manager 42 * owned by {@link ColorFilter_Delegate}. 43 * 44 * @see ColorFilter_Delegate 45 * 46 */ 47 public class PorterDuffColorFilter_Delegate extends ColorFilter_Delegate { 48 49 // ---- delegate data ---- 50 51 private final java.awt.Color mSrcColor; 52 private final Mode mMode; 53 54 55 // ---- Public Helper methods ---- 56 57 @Override 58 public boolean isSupported() { 59 return true; 60 } 61 62 @Override 63 public String getSupportMessage() { 64 return "PorterDuff Color Filter is not supported for mode: " + mMode.name() + "."; 65 } 66 67 @Override 68 public void applyFilter(Graphics2D g, int width, int height) { 69 g.setComposite(getComposite(mMode, 0xFF)); 70 g.setColor(mSrcColor); 71 g.fillRect(0, 0, width, height); 72 } 73 74 // ---- native methods ---- 75 76 @LayoutlibDelegate 77 /*package*/ static long native_CreatePorterDuffFilter(int srcColor, int porterDuffMode) { 78 PorterDuffColorFilter_Delegate newDelegate = 79 new PorterDuffColorFilter_Delegate(srcColor, porterDuffMode); 80 return sManager.addNewDelegate(newDelegate); 81 } 82 83 84 // ---- Private delegate/helper methods ---- 85 86 private PorterDuffColorFilter_Delegate(int srcColor, int mode) { 87 mSrcColor = new java.awt.Color(srcColor, true /* hasAlpha */); 88 mMode = getCompatibleMode(getPorterDuffMode(mode)); 89 } 90 91 // For filtering the colors, the src image should contain the "color" only for pixel values 92 // which are not transparent in the target image. But, we are using a simple rectangular image 93 // completely filled with color. Hence some Composite rules do not apply as intended. However, 94 // in such cases, they can usually be mapped to some other mode, which produces an approximately 95 // equivalent result. 96 private Mode getCompatibleMode(Mode mode) { 97 Mode m = mode; 98 // Modes that are directly supported: 99 // CLEAR, DST, SRC_IN, DST_IN, DST_OUT, SRC_ATOP, DARKEN, LIGHTEN, MULTIPLY, SCREEN, 100 // ADD, OVERLAY 101 switch (mode) { 102 // Modes that can be mapped to one of the supported modes. 103 case SRC: 104 m = Mode.SRC_IN; 105 break; 106 case SRC_OVER: 107 m = Mode.SRC_ATOP; 108 break; 109 case DST_OVER: 110 m = Mode.DST; 111 break; 112 case SRC_OUT: 113 m = Mode.CLEAR; 114 break; 115 case DST_ATOP: 116 m = Mode.DST_IN; 117 break; 118 case XOR: 119 m = Mode.DST_OUT; 120 break; 121 } 122 return m; 123 } 124 } 125