/* * Copyright (C) 2010 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; import com.android.ide.common.rendering.api.LayoutLog; import com.android.layoutlib.bridge.Bridge; import com.android.layoutlib.bridge.impl.DelegateManager; import com.android.tools.layoutlib.annotations.LayoutlibDelegate; /** * Delegate implementing the native methods of android.graphics.SweepGradient * * Through the layoutlib_create tool, the original native methods of SweepGradient have been * replaced by calls to methods of the same name in this delegate class. * * This class behaves like the original native implementation, but in Java, keeping previously * native data into its own objects and mapping them to int that are sent back and forth between * it and the original SweepGradient class. * * Because this extends {@link Shader_Delegate}, there's no need to use a {@link DelegateManager}, * as all the Shader classes will be added to the manager owned by {@link Shader_Delegate}. * * @see Shader_Delegate * */ public class SweepGradient_Delegate extends Gradient_Delegate { // ---- delegate data ---- private java.awt.Paint mJavaPaint; // ---- Public Helper methods ---- @Override public java.awt.Paint getJavaPaint() { return mJavaPaint; } // ---- native methods ---- @LayoutlibDelegate /*package*/ static long nativeCreate1(long matrix, float x, float y, int colors[], float positions[]) { SweepGradient_Delegate newDelegate = new SweepGradient_Delegate(matrix, x, y, colors, positions); return sManager.addNewDelegate(newDelegate); } @LayoutlibDelegate /*package*/ static long nativeCreate2(long matrix, float x, float y, int color0, int color1) { return nativeCreate1(matrix, x, y, new int[] { color0, color1 }, null /*positions*/); } // ---- Private delegate/helper methods ---- /** * A subclass of Shader that draws a sweep gradient around a center point. * * @param nativeMatrix reference to the shader's native transformation matrix * @param cx The x-coordinate of the center * @param cy The y-coordinate of the center * @param colors The colors to be distributed between around the center. * There must be at least 2 colors in the array. * @param positions May be NULL. The relative position of * each corresponding color in the colors array, beginning * with 0 and ending with 1.0. If the values are not * monotonic, the drawing may produce unexpected results. * If positions is NULL, then the colors are automatically * spaced evenly. */ private SweepGradient_Delegate(long nativeMatrix, float cx, float cy, int colors[], float positions[]) { super(nativeMatrix, colors, positions); mJavaPaint = new SweepGradientPaint(cx, cy, mColors, mPositions); } private class SweepGradientPaint extends GradientPaint { private final float mCx; private final float mCy; public SweepGradientPaint(float cx, float cy, int[] colors, float[] positions) { super(colors, positions, null /*tileMode*/); mCx = cx; mCy = cy; } @Override 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(); java.awt.geom.AffineTransform canvasMatrix; try { canvasMatrix = xform.createInverse(); } catch (java.awt.geom.NoninvertibleTransformException e) { Bridge.getLog().fidelityWarning(LayoutLog.TAG_MATRIX_INVERSE, "Unable to inverse matrix in SweepGradient", e, null /*data*/); canvasMatrix = new java.awt.geom.AffineTransform(); } java.awt.geom.AffineTransform localMatrix = getLocalMatrix(); try { localMatrix = localMatrix.createInverse(); } catch (java.awt.geom.NoninvertibleTransformException e) { Bridge.getLog().fidelityWarning(LayoutLog.TAG_MATRIX_INVERSE, "Unable to inverse matrix in SweepGradient", e, null /*data*/); localMatrix = new java.awt.geom.AffineTransform(); } return new SweepGradientPaintContext(canvasMatrix, localMatrix, colorModel); } private class SweepGradientPaintContext implements java.awt.PaintContext { private final java.awt.geom.AffineTransform mCanvasMatrix; private final java.awt.geom.AffineTransform mLocalMatrix; private final java.awt.image.ColorModel mColorModel; public SweepGradientPaintContext( java.awt.geom.AffineTransform canvasMatrix, java.awt.geom.AffineTransform localMatrix, java.awt.image.ColorModel colorModel) { mCanvasMatrix = canvasMatrix; mLocalMatrix = localMatrix; mColorModel = colorModel; } @Override public void dispose() { } @Override public java.awt.image.ColorModel getColorModel() { return mColorModel; } @Override public java.awt.image.Raster getRaster(int x, int y, int w, int h) { java.awt.image.BufferedImage image = new java.awt.image.BufferedImage( mColorModel, mColorModel.createCompatibleWritableRaster(w, h), mColorModel.isAlphaPremultiplied(), null); int[] data = new int[w*h]; // compute angle from each point to the center, and figure out the distance from // it. int index = 0; float[] pt1 = new float[2]; float[] pt2 = new float[2]; for (int iy = 0 ; iy < h ; iy++) { for (int ix = 0 ; ix < w ; ix++) { // handle the canvas transform pt1[0] = x + ix; pt1[1] = y + iy; mCanvasMatrix.transform(pt1, 0, pt2, 0, 1); // handle the local matrix pt1[0] = pt2[0] - mCx; pt1[1] = pt2[1] - mCy; mLocalMatrix.transform(pt1, 0, pt2, 0, 1); float dx = pt2[0]; float dy = pt2[1]; float angle; if (dx == 0) { angle = (float) (dy < 0 ? 3 * Math.PI / 2 : Math.PI / 2); } else if (dy == 0) { angle = (float) (dx < 0 ? Math.PI : 0); } else { angle = (float) Math.atan(dy / dx); if (dx > 0) { if (dy < 0) { angle += Math.PI * 2; } } else { angle += Math.PI; } } // convert to 0-1. value and get color data[index++] = getGradientColor((float) (angle / (2 * Math.PI))); } } image.setRGB(0 /*startX*/, 0 /*startY*/, w, h, data, 0 /*offset*/, w /*scansize*/); return image.getRaster(); } } } }