/*
* Copyright 2009 Hao Nguyen
*
* 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 gwt.g2d.client.demo;
import gwt.g2d.client.graphics.Gradient;
import gwt.g2d.client.graphics.KnownColor;
import gwt.g2d.client.graphics.RadialGradient;
import gwt.g2d.client.graphics.Surface;
import gwt.g2d.client.graphics.shapes.Shape;
import gwt.g2d.client.graphics.shapes.ShapeBuilder;
import gwt.g2d.client.math.Circle;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.Panel;
/**
* Demo the use of drawing canvas onto canvas.
*
* @author hao1300@gmail.com
*/
public class CanvasOnCanvasDemo extends AbstractDemo {
public CanvasOnCanvasDemo(Panel parentContainer) {
super("Canvas on Canvas Demo", parentContainer);
}
@Override
public void initialize() {
add(new Label("This demo does not work under IE."));
Surface originalCanvas = new Surface(300, 300);
Circle smallCircle = new Circle(150, 150, 140);
Circle bigCircle = new Circle(150, 150, 150);
Shape smallCircleShape = new ShapeBuilder().drawCircle(smallCircle).build();
Shape bigCircleShape = new ShapeBuilder().drawCircle(bigCircle).build();
Gradient radialGradient = new RadialGradient(new Circle(150, 150, 0), smallCircle)
.addColorStop(0, KnownColor.RED)
.addColorStop(1, KnownColor.GREEN);
originalCanvas.setFillStyle(KnownColor.BLACK)
.fillShape(bigCircleShape)
.setFillStyle(radialGradient)
.fillShape(smallCircleShape);
add(new Label("Original Canvas"));
add(originalCanvas);
add(new Label("Canvas with the original canvas drawn on top of it."));
add(getPrimarySurface());
getPrimarySurface().clear()
.fillBackground(KnownColor.GRAY)
.drawImage(originalCanvas.getCanvas(), 0, 0)
.drawImage(originalCanvas.getCanvas(), 300, 0)
.drawImage(originalCanvas.getCanvas(), 0, 300)
.drawImage(originalCanvas.getCanvas(), 300, 300)
.drawImage(originalCanvas.getCanvas(), 150, 150);
}
@Override
public void update() {
}
}