| /* |
| * Copyright (C) 2008 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; |
| |
| public class RadialGradient extends GradientShader { |
| |
| private RadialGradientPaint mPaint; |
| |
| /** |
| * Create a shader that draws a radial gradient given the center and radius. |
| * |
| * @param x The x-coordinate of the center of the radius |
| * @param y The y-coordinate of the center of the radius |
| * @param radius Must be positive. The radius of the circle for this |
| * gradient |
| * @param colors The colors to be distributed between the center and edge of |
| * the circle |
| * @param positions May be NULL. The relative position of each corresponding |
| * color in the colors array. If this is NULL, the the colors are |
| * distributed evenly between the center and edge of the circle. |
| * @param tile The Shader tiling mode |
| */ |
| public RadialGradient(float x, float y, float radius, int colors[], float positions[], |
| TileMode tile) { |
| super(colors, positions); |
| if (radius <= 0) { |
| throw new IllegalArgumentException("radius must be > 0"); |
| } |
| |
| mPaint = new RadialGradientPaint(x, y, radius, mColors, mPositions, tile); |
| } |
| |
| /** |
| * Create a shader that draws a radial gradient given the center and radius. |
| * |
| * @param x The x-coordinate of the center of the radius |
| * @param y The y-coordinate of the center of the radius |
| * @param radius Must be positive. The radius of the circle for this |
| * gradient |
| * @param color0 The color at the center of the circle. |
| * @param color1 The color at the edge of the circle. |
| * @param tile The Shader tiling mode |
| */ |
| public RadialGradient(float x, float y, float radius, int color0, int color1, TileMode tile) { |
| this(x, y, radius, new int[] { color0, color1 }, null /* positions */, tile); |
| } |
| |
| @Override |
| java.awt.Paint getJavaPaint() { |
| return mPaint; |
| } |
| |
| private static class RadialGradientPaint extends GradientPaint { |
| |
| private final float mX; |
| private final float mY; |
| private final float mRadius; |
| |
| public RadialGradientPaint(float x, float y, float radius, int[] colors, float[] positions, TileMode mode) { |
| super(colors, positions, mode); |
| mX = x; |
| mY = y; |
| mRadius = radius; |
| } |
| |
| public java.awt.PaintContext createContext( |
| java.awt.image.ColorModel colorModel, |
| java.awt.Rectangle deviceBounds, |
| java.awt.geom.Rectangle2D userBounds, |
| java.awt.geom.AffineTransform xform, |
| java.awt.RenderingHints hints) { |
| precomputeGradientColors(); |
| return new RadialGradientPaintContext(colorModel); |
| } |
| |
| private class RadialGradientPaintContext implements java.awt.PaintContext { |
| |
| private final java.awt.image.ColorModel mColorModel; |
| |
| public RadialGradientPaintContext(java.awt.image.ColorModel colorModel) { |
| mColorModel = colorModel; |
| } |
| |
| public void dispose() { |
| } |
| |
| public java.awt.image.ColorModel getColorModel() { |
| return mColorModel; |
| } |
| |
| public java.awt.image.Raster getRaster(int x, int y, int w, int h) { |
| java.awt.image.BufferedImage image = new java.awt.image.BufferedImage(w, h, |
| java.awt.image.BufferedImage.TYPE_INT_ARGB); |
| |
| int[] data = new int[w*h]; |
| |
| // compute distance from each point to the center, and figure out the distance from |
| // it. |
| int index = 0; |
| for (int iy = 0 ; iy < h ; iy++) { |
| for (int ix = 0 ; ix < w ; ix++) { |
| float _x = x + ix - mX; |
| float _y = y + iy - mY; |
| float distance = (float) Math.sqrt(_x * _x + _y * _y); |
| |
| data[index++] = getGradientColor(distance / mRadius); |
| } |
| } |
| |
| image.setRGB(0 /*startX*/, 0 /*startY*/, w, h, data, 0 /*offset*/, w /*scansize*/); |
| |
| return image.getRaster(); |
| } |
| |
| } |
| } |
| |
| } |