/*
* 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(float x, float y, int colors[], float positions[]) {
SweepGradient_Delegate newDelegate = new SweepGradient_Delegate(x, y, colors, positions);
return sManager.addNewDelegate(newDelegate);
}
@LayoutlibDelegate
/*package*/ static long nativeCreate2(float x, float y, int color0, int color1) {
return nativeCreate1(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 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(float cx, float cy,
int colors[], float positions[]) {
super(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(w, h,
java.awt.image.BufferedImage.TYPE_INT_ARGB);
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();
}
}
}
}
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