| /* |
| * Copyright (C) 2009 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package android.graphics.cts; |
| |
| |
| import android.graphics.Bitmap; |
| import android.graphics.Canvas; |
| import android.graphics.Color; |
| import android.graphics.Paint; |
| import android.graphics.Rect; |
| import android.graphics.Shader; |
| import android.graphics.SweepGradient; |
| import android.graphics.Bitmap.Config; |
| |
| import junit.framework.TestCase; |
| |
| public class SweepGradientTest extends TestCase { |
| |
| private Paint mPaint; |
| private Canvas mCanvas; |
| private Bitmap mBitmap; |
| |
| private static final int SIZE = 200; |
| private static final int CENTER = SIZE / 2; |
| private static final int RADIUS = 80; |
| private static final int NUM_STEPS = 100; |
| private static final int TOLERANCE = 10; |
| |
| @Override |
| protected void setUp() throws Exception { |
| super.setUp(); |
| mPaint = new Paint(); |
| mBitmap = Bitmap.createBitmap(SIZE, SIZE, Config.ARGB_8888); |
| mBitmap.eraseColor(Color.TRANSPARENT); |
| mCanvas = new Canvas(mBitmap); |
| } |
| |
| public void test2Colors() { |
| final int[] colors = new int[] { Color.GREEN, Color.RED }; |
| final float[] positions = new float[] { 0f, 1f }; |
| Shader shader = new SweepGradient(CENTER, CENTER, colors[0], colors[1]); |
| mPaint.setShader(shader); |
| mCanvas.drawRect(new Rect(0, 0, SIZE, SIZE), mPaint); |
| checkColors(colors, positions, TOLERANCE); |
| } |
| |
| public void testColorArray() { |
| final int[] colors = new int[] { Color.GREEN, Color.RED, Color.BLUE }; |
| final float[] positions = new float[] { 0f, 0.3f, 1f }; |
| Shader shader = new SweepGradient(CENTER, CENTER, colors, positions); |
| mPaint.setShader(shader); |
| mCanvas.drawRect(new Rect(0, 0, SIZE, SIZE), mPaint); |
| |
| checkColors(colors, positions, TOLERANCE); |
| } |
| |
| public void testMultiColor() { |
| final int[] colors = new int[] { Color.GREEN, Color.RED, Color.BLUE, Color.GREEN }; |
| final float[] positions = new float[] { 0f, 0.25f, 0.5f, 1f }; |
| |
| Shader shader = new SweepGradient(CENTER, CENTER, colors, positions); |
| mPaint.setShader(shader); |
| mCanvas.drawRect(new Rect(0, 0, SIZE, SIZE), mPaint); |
| |
| checkColors(colors, positions, TOLERANCE); |
| } |
| |
| private void checkColors(int[] colors, float[] positions, int tolerance) { |
| final double twoPi = Math.PI * 2; |
| final double step = twoPi / NUM_STEPS; |
| |
| // exclude angle 0, which is not defined |
| for (double rad = step; rad <= twoPi - step; rad += step) { |
| int x = CENTER + (int)(Math.cos(rad) * RADIUS); |
| int y = CENTER + (int)(Math.sin(rad) * RADIUS); |
| |
| float relPos = (float)(rad / twoPi); |
| int idx; |
| int color; |
| for (idx = 0; idx < positions.length; idx++) { |
| if (positions[idx] > relPos) { |
| break; |
| } |
| } |
| if (idx == 0) { |
| // use start color |
| color = colors[0]; |
| } else if (idx == positions.length) { |
| // clamp to end color |
| color = colors[positions.length - 1]; |
| } else { |
| // linear interpolation |
| int i1 = idx - 1; // index of next lower color and position |
| int i2 = idx; // index of next higher color and position |
| double delta = (relPos - positions[i1]) / (positions[i2] - positions[i1]); |
| int alpha = (int) ((1d - delta) * Color.alpha(colors[i1]) + |
| delta * Color.alpha(colors[i2])); |
| int red = (int) ((1d - delta) * Color.red(colors[i1]) + |
| delta * Color.red(colors[i2])); |
| int green = (int) ((1d - delta) * Color.green(colors[i1]) + |
| delta * Color.green(colors[i2])); |
| int blue = (int) ((1d - delta) * Color.blue(colors[i1]) + |
| delta * Color.blue(colors[i2])); |
| color = Color.argb(alpha, red, green, blue); |
| } |
| |
| int pixel = mBitmap.getPixel(x, y); |
| |
| try { |
| assertEquals(Color.alpha(color), Color.alpha(pixel), tolerance); |
| assertEquals(Color.red(color), Color.red(pixel), tolerance); |
| assertEquals(Color.green(color), Color.green(pixel), tolerance); |
| assertEquals(Color.blue(color), Color.blue(pixel), tolerance); |
| } catch (Error e) { |
| System.out.println("***************"); |
| System.out.println(rad); |
| System.out.println(x); |
| System.out.println(y); |
| System.out.println(Integer.toHexString(pixel)); |
| System.out.println(Integer.toHexString(color)); |
| throw e; |
| } |
| } |
| } |
| } |