1 /* 2 * Copyright (C) 2009 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.cts; 18 19 import static org.junit.Assert.assertEquals; 20 import static org.junit.Assert.assertTrue; 21 22 import android.graphics.Bitmap; 23 import android.graphics.Bitmap.Config; 24 import android.graphics.Canvas; 25 import android.graphics.Color; 26 import android.graphics.DiscretePathEffect; 27 import android.graphics.Paint; 28 import android.graphics.Paint.Style; 29 import android.graphics.Path; 30 import android.graphics.PorterDuff.Mode; 31 import android.graphics.PorterDuffXfermode; 32 33 import androidx.test.filters.SmallTest; 34 import androidx.test.runner.AndroidJUnit4; 35 36 import org.junit.Test; 37 import org.junit.runner.RunWith; 38 39 @SmallTest 40 @RunWith(AndroidJUnit4.class) 41 public class DiscretePathEffectTest { 42 private static final int BITMAP_WIDTH = 200; 43 private static final int BITMAP_HEIGHT = 100; 44 private static final int START_X = 10; 45 private static final int END_X = BITMAP_WIDTH - START_X; 46 private static final int COORD_Y = BITMAP_HEIGHT / 2; 47 private static final int SEGMENT_LENGTH = 10; // must be < BITMAP_WIDTH 48 private static final int DEVIATION = 10; // must be < BITMAP_HEIGHT 49 50 @Test testDiscretePathEffect()51 public void testDiscretePathEffect() { 52 DiscretePathEffect effect = new DiscretePathEffect(SEGMENT_LENGTH, DEVIATION); 53 54 Paint paint = new Paint(); 55 paint.setColor(Color.GREEN); 56 paint.setStyle(Style.STROKE); 57 paint.setStrokeWidth(0); 58 paint.setPathEffect(effect); 59 60 Path path = new Path(); 61 path.moveTo(START_X, COORD_Y); 62 path.lineTo(END_X, COORD_Y); 63 64 Bitmap bitmap = Bitmap.createBitmap(BITMAP_WIDTH, BITMAP_HEIGHT, Config.ARGB_8888); 65 bitmap.eraseColor(Color.TRANSPARENT); 66 67 Canvas canvas = new Canvas(bitmap); 68 canvas.drawPath(path, paint); 69 70 // draw guide line into red channel (each segment should cross this once) 71 paint = new Paint(); 72 paint.setColor(Color.RED); 73 paint.setStyle(Style.STROKE); 74 paint.setStrokeWidth(0); 75 paint.setXfermode(new PorterDuffXfermode(Mode.SCREEN)); 76 canvas.drawPath(path, paint); 77 78 // draw guide rectangle into blue channel (each segment must be completely inside this) 79 paint.setColor(Color.BLUE); 80 paint.setStrokeWidth(1 + 2 * DEVIATION); 81 canvas.drawPath(path, paint); 82 83 int intersect = 0; 84 int numGreenPixels = 0; 85 int minY = BITMAP_HEIGHT; 86 int maxY = 0; 87 for (int y = 0; y < BITMAP_HEIGHT; y++) { 88 for (int x = 0; x < BITMAP_WIDTH; x++) { 89 int pixel = bitmap.getPixel(x, y); 90 if (Color.green(pixel) > 0) { 91 numGreenPixels += 1; 92 minY = Math.min(minY, y); 93 maxY = Math.max(maxY, y); 94 assertEquals(0xFF, Color.blue(pixel)); 95 if (Color.red(pixel) > 0) { 96 intersect += 1; 97 } 98 } 99 } 100 } 101 int lineLength = END_X - START_X; 102 // the number of pixels in all segments must be at least the same as the line length 103 assertTrue(numGreenPixels >= lineLength); 104 // green line must vary in y direction 105 assertTrue(maxY - minY > 0); 106 // ... but not too much 107 assertTrue(maxY - minY <= 1 + 2 * DEVIATION); 108 // intersecting pixels must be less than line length, otherwise deviation doesn't work 109 assertTrue(intersect < lineLength); 110 // there must be at least as many intersecting pixels as there are full segments 111 assertTrue(intersect >= lineLength / SEGMENT_LENGTH); 112 } 113 } 114