AvoidXfermode.java revision 736c525a04a4d5e1c83541deca009ca97b99ef92
1/* 2 * Copyright (C) 2008 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 17package android.graphics; 18 19/** 20 * AvoidXfermode xfermode will draw the src everywhere except on top of the 21 * opColor or, depending on the Mode, draw only on top of the opColor. 22 */ 23public class AvoidXfermode extends Xfermode { 24 25 // these need to match the enum in SkAvoidXfermode.h on the native side 26 public enum Mode { 27 AVOID (0), //!< draw everywhere except on the opColor 28 TARGET (1); //!< draw only on top of the opColor 29 30 Mode(int nativeInt) { 31 this.nativeInt = nativeInt; 32 } 33 final int nativeInt; 34 } 35 36 /** This xfermode draws, or doesn't draw, based on the destination's 37 * distance from an op-color. 38 * 39 * There are two modes, and each mode interprets a tolerance value. 40 * 41 * AVOID: In this mode, drawing is allowed only on destination pixels that 42 * are different from the op-color. 43 * Tolerance near 0: avoid anything close to the op-color 44 * Tolerance near 255: avoid only colors very close to the op-color 45 * 46 * TARGET: In this mode, drawing only occurs on destination pixels that 47 * are similar to the op-color 48 * Tolerance near 0: draw on colors that are very close to op-color 49 * Tolerance near 255: draw on colors that to the op-color 50 */ 51 public AvoidXfermode(int opColor, int tolerance, Mode mode) { 52 if (tolerance < 0 || tolerance > 255) { 53 throw new IllegalArgumentException("tolerance must be 0..255"); 54 } 55 native_instance = nativeCreate(opColor, tolerance, mode.nativeInt); 56 } 57 58 private static native int nativeCreate(int opColor, int tolerance, 59 int nativeMode); 60} 61