com.akjava.gwt.threetest.client.CanvasDemo.java Source code

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Here is the source code for com.akjava.gwt.threetest.client.CanvasDemo.java

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/*
 * Copyright (C) 2011 aki@akjava.com
 *
 * 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 com.akjava.gwt.threetest.client;

import com.akjava.gwt.lib.client.ExportUtils;
import com.akjava.gwt.three.client.THREE;
import com.akjava.gwt.three.client.cameras.Camera;
import com.akjava.gwt.three.client.lights.Light;
import com.akjava.gwt.three.client.objects.Mesh;
import com.akjava.gwt.three.client.renderers.WebGLRenderer;
import com.akjava.gwt.three.client.scenes.Scene;
import com.akjava.gwt.three.client.textures.Texture;
import com.akjava.gwt.threetest.client.resources.Bundles;
import com.google.gwt.canvas.client.Canvas;
import com.google.gwt.dom.client.ImageElement;
import com.google.gwt.dom.client.NativeEvent;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.event.dom.client.MouseMoveEvent;
import com.google.gwt.user.client.Timer;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.FocusPanel;
import com.google.gwt.user.client.ui.Image;
import com.google.gwt.user.client.ui.Widget;

public class CanvasDemo extends AbstractDemo {

    @Override
    public void start(final WebGLRenderer renderer, final int width, final int height, FocusPanel panel) {
        super.start(renderer, width, height, panel);
        canvas = Canvas.createIfSupported();
        canvas.setCoordinateSpaceWidth(100);
        canvas.setCoordinateSpaceHeight(100);
        canvas.getContext2d().setFillStyle("#cccccc");
        canvas.getContext2d().fillRect(0, 0, canvas.getCoordinateSpaceWidth(), canvas.getCoordinateSpaceHeight());
        canvas.getContext2d().strokeText("Hello World", 25, 25);
        String url = canvas.toDataUrl();
        Image img = new Image(url);
        ImageElement imageElement = ImageElement.as(img.getElement());
        Texture texture = THREE.Texture(imageElement);
        texture.setNeedsUpdate(true);

        final Scene scene = THREE.Scene();
        final Camera camera = THREE.PerspectiveCamera(35, (double) width / height, .1, 10000);
        scene.add(camera);
        cameraControle.setPositionZ(20);

        final Mesh mesh = THREE.Mesh(THREE.CubeGeometry(5, 5, 5), THREE.MeshLambertMaterial().map(texture).build());
        scene.add(mesh);

        final Light light = THREE.PointLight(0xffffff);
        light.setPosition(10, 0, 10);
        scene.add(light);

        Timer timer = new Timer() {
            public void run() {
                MainWidget.stats.update();
                camera.setPosition(cameraControle.getPositionX(), cameraControle.getPositionY(),
                        cameraControle.getPositionZ());

                mesh.setRotation(cameraControle.getRadiantRotationX(), cameraControle.getRadiantRotationY(),
                        cameraControle.getRadiantRotationZ());

                renderer.render(scene, camera);
            }
        };

        startTimer(timer);
    }

    @Override
    public void onMouseMove(MouseMoveEvent event) {
        super.onMouseMove(event);
        if (event.getNativeButton() == NativeEvent.BUTTON_LEFT && mouseDown) {
            int diffX = event.getX() - mouseDownX;
            int diffY = event.getY() - mouseDownY;
            mouseDownX = event.getX();
            mouseDownY = event.getY();

            cameraControle.incrementRotationX(diffY);
            cameraControle.incrementRotationY(diffX);
        }
    }

    Button exportButton;
    private Canvas canvas;

    @Override
    public Widget getControler() {
        if (exportButton == null) {
            exportButton = new Button("Export Image");
            exportButton.addClickHandler(new ClickHandler() {

                @Override
                public void onClick(ClickEvent event) {
                    String url = canvas.toDataUrl();
                    ExportUtils.openTabAbsoluteURLImage(url, "canvastest");
                }
            });
        }
        return exportButton;
    }

    @Override
    public String getName() {
        return "Canvas";
    }

    @Override
    public String getHowToHtml() {
        return Bundles.INSTANCE.canvas().getText();
    }
}