skrueger/geotools/RenderingExecutor.java

package skrueger.geotools;

import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.geom.AffineTransform;

import javax.swing.SwingUtilities;

import org.geotools.geometry.jts.ReferencedEnvelope;
import org.geotools.renderer.GTRenderer;
import org.geotools.renderer.RenderListener;
import org.opengis.feature.simple.SimpleFeature;

import schmitzm.swing.SwingUtil;

/**
 * This class is used by {@link XMapPane} to start and stop the rendering a
 * {@link Thread} for rendering.
 */
class RenderingExecutor {

        /**
         * Instance to a {@link RenderThread} doing any work. It's volatile so the
         * correct value will always be visible to any {@link Thread}
         **/
        private volatile RenderThread renderThread;

        private final XMapPane mapPane;

        public RenderingExecutor(XMapPane mapPane) {
                this.mapPane = mapPane;
        }

        /**
         * Submit a new rendering task. If no rendering task is presently running
         * this new job will be accepted; otherwise it will be rejected and it
         * returns <code>false</code>.
         * 
         * @param envelope
         *            the map area (world coordinates) to be rendered.
         * @param graphics
         *            the graphics object to draw on.
         * @param paintArea
         *            size of the area to paint the world into.
         * @param worldToScreen
         *            the {@link AffineTransform} from world coordinates to screen
         *            coordinates.
         * @param renderer
         *            the {@link GTRenderer} to use.
         * 
         * @return true if the rendering task was accepted; false if it was rejected
         */
        public synchronized boolean submit(ReferencedEnvelope envelope,
                        Rectangle paintArea, Graphics2D graphics,
                        final GTRenderer renderer, AffineTransform worldToScreen) {
                if (renderThread == null || !renderThread.isAlive()) {
                        // System.out.println("is vacant... starting thread!");
                        renderThread = null;

                        renderThread = new RenderThread(paintArea, graphics, renderer,
                                        worldToScreen);
                        renderThread.start();

                        return true;
                } else {
                        // System.out.println("is busy... requesting stop!");
                        renderThread.getRenderer().stopRendering();
                        return false;
                }
        }

        /**
         * For every new rendering job submitted and accepted, an instance of this
         * {@link Thread} will be started.
         * 
         */
        class RenderThread extends Thread {

                private final GTRenderer renderer;

                public RenderThread(final Rectangle paintArea,
                                final Graphics2D graphics, GTRenderer renderer,
                                AffineTransform worldToScreen) {
                        super(new RenderRun(paintArea, graphics, renderer, worldToScreen));
                        this.renderer = renderer;

                        setName("Render" + getName());

                        // System.out.println("starting render thread " + getName());
                }

                public GTRenderer getRenderer() {
                        return renderer;
                }

        }

        /**
         * This {@link Runnable} will actually start the rendering
         */
        class RenderRun implements Runnable, RenderListener {
                private final Rectangle paintArea;
                private final Graphics2D graphics;
                private final AffineTransform worldToScreen;
                private final GTRenderer renderer;

                public RenderRun(Rectangle paintArea, Graphics2D graphics,
                                GTRenderer renderer, AffineTransform worldToScreen) {
                        this.paintArea = paintArea;
                        this.graphics = graphics;
                        this.renderer = renderer;
                        this.worldToScreen = worldToScreen;
                }

                @Override
                public void run() {
                        try {
                                renderer.addRenderListener(this);
                                System.out.println("start rendering...");
                                // try {
                                // Thread.sleep(1000);
                                // } catch (InterruptedException e) {
                                // e.printStackTrace();
                                // }

                                // Clear the graphics context
                                graphics.setBackground(mapPane.getMapBackgroundColor());
                                graphics.clearRect(paintArea.x, paintArea.y, paintArea.width,
                                                paintArea.height);

                                renderer.paint(graphics, paintArea, worldToScreen);

                                // Invoked later, so when onRenderingCompleted is called, the Thread is not running anymore (#isRunning = false)
                                SwingUtilities.invokeLater(new Runnable() {
                                        @Override
                                        public void run() {
                                                mapPane.onRenderingCompleted();
                                        };
                                });
                        } finally {
                                renderer.removeRenderListener(this);
                        }
                }

                @Override
                public void errorOccurred(Exception e) {
                        // System.out.println("rendering error");
                        mapPane.onRenderingFailed(e);
                }

                @Override
                public void featureRenderer(SimpleFeature feature) {
                }

        }

        /**
         * Ask to stop the rendering. May be called often.
         */
        public void cancelTask() {
                if (renderThread != null && renderThread.isAlive()) {
                        // System.out.println("request stop for thread " +task.getName());
                        renderThread.getRenderer().stopRendering();
                }
        }

        /**
         * @return <code>true</code> if the {@link Thread} is busy rendering.
         */
        public boolean isRunning() {
                // if (task != null)
                // System.out.println("is running "+task.getName()+" = true");
                return (renderThread != null && renderThread.isAlive());
        }

        /**
         * Will stop rendering and remove the reference to the {@link Thread}.
         */
        public void dispose() {
                if (renderThread != null) {
                        renderThread.renderer.stopRendering();
                        renderThread = null;
                }
        }

}
1	alfonx	510	package skrueger.geotools;
2
3			import java.awt.Graphics2D;
4			import java.awt.Rectangle;
5	alfonx	529	import java.awt.geom.AffineTransform;
6	alfonx	510
7	alfonx	532	import javax.swing.SwingUtilities;
8
9	alfonx	510	import org.geotools.geometry.jts.ReferencedEnvelope;
10			import org.geotools.renderer.GTRenderer;
11			import org.geotools.renderer.RenderListener;
12			import org.opengis.feature.simple.SimpleFeature;
13
14	alfonx	532	import schmitzm.swing.SwingUtil;
15	alfonx	510
16	alfonx	532	/**
17			* This class is used by {@link XMapPane} to start and stop the rendering a
18			* {@link Thread} for rendering.
19			*/
20			class RenderingExecutor {
21
22			/**
23			* Instance to a {@link RenderThread} doing any work. It's volatile so the
24			* correct value will always be visible to any {@link Thread}
25			**/
26	alfonx	530	private volatile RenderThread renderThread;
27	alfonx	532
28	alfonx	530	private final XMapPane mapPane;
29
30	alfonx	529	public RenderingExecutor(XMapPane mapPane) {
31			this.mapPane = mapPane;
32	alfonx	530	}
33	alfonx	510
34	alfonx	530	/**
35			* Submit a new rendering task. If no rendering task is presently running
36	alfonx	532	* this new job will be accepted; otherwise it will be rejected and it
37			* returns <code>false</code>.
38	alfonx	530	*
39			* @param envelope
40	alfonx	532	* the map area (world coordinates) to be rendered.
41	alfonx	530	* @param graphics
42	alfonx	532	* the graphics object to draw on.
43			* @param paintArea
44			* size of the area to paint the world into.
45			* @param worldToScreen
46			* the {@link AffineTransform} from world coordinates to screen
47			* coordinates.
48			* @param renderer
49			* the {@link GTRenderer} to use.
50	alfonx	530	*
51			* @return true if the rendering task was accepted; false if it was rejected
52			*/
53			public synchronized boolean submit(ReferencedEnvelope envelope,
54			Rectangle paintArea, Graphics2D graphics,
55			final GTRenderer renderer, AffineTransform worldToScreen) {
56			if (renderThread == null \|\| !renderThread.isAlive()) {
57	alfonx	532	// System.out.println("is vacant... starting thread!");
58			renderThread = null;
59	alfonx	510
60	alfonx	530	renderThread = new RenderThread(paintArea, graphics, renderer,
61			worldToScreen);
62			renderThread.start();
63	alfonx	510
64	alfonx	530	return true;
65			} else {
66	alfonx	532	// System.out.println("is busy... requesting stop!");
67	alfonx	530	renderThread.getRenderer().stopRendering();
68	alfonx	532	return false;
69	alfonx	530	}
70			}
71
72	alfonx	532	/**
73			* For every new rendering job submitted and accepted, an instance of this
74			* {@link Thread} will be started.
75			*
76			*/
77	alfonx	530	class RenderThread extends Thread {
78
79			private final GTRenderer renderer;
80
81			public RenderThread(final Rectangle paintArea,
82			final Graphics2D graphics, GTRenderer renderer,
83			AffineTransform worldToScreen) {
84			super(new RenderRun(paintArea, graphics, renderer, worldToScreen));
85	alfonx	529	this.renderer = renderer;
86	alfonx	530
87	alfonx	532	setName("Render" + getName());
88
89			// System.out.println("starting render thread " + getName());
90	alfonx	529	}
91	alfonx	530
92			public GTRenderer getRenderer() {
93	alfonx	529	return renderer;
94			}
95
96	alfonx	530	}
97
98	alfonx	532	/**
99			* This {@link Runnable} will actually start the rendering
100			*/
101	alfonx	530	class RenderRun implements Runnable, RenderListener {
102			private final Rectangle paintArea;
103	alfonx	529	private final Graphics2D graphics;
104			private final AffineTransform worldToScreen;
105			private final GTRenderer renderer;
106	alfonx	510
107	alfonx	529	public RenderRun(Rectangle paintArea, Graphics2D graphics,
108			GTRenderer renderer, AffineTransform worldToScreen) {
109	alfonx	530	this.paintArea = paintArea;
110			this.graphics = graphics;
111			this.renderer = renderer;
112			this.worldToScreen = worldToScreen;
113	alfonx	529	}
114	alfonx	530
115	alfonx	529	@Override
116			public void run() {
117			try {
118	alfonx	530	renderer.addRenderListener(this);
119			System.out.println("start rendering...");
120	alfonx	532	// try {
121			// Thread.sleep(1000);
122			// } catch (InterruptedException e) {
123			// e.printStackTrace();
124			// }
125
126			// Clear the graphics context
127			graphics.setBackground(mapPane.getMapBackgroundColor());
128			graphics.clearRect(paintArea.x, paintArea.y, paintArea.width,
129			paintArea.height);
130
131	alfonx	530	renderer.paint(graphics, paintArea, worldToScreen);
132
133	alfonx	532	// Invoked later, so when onRenderingCompleted is called, the Thread is not running anymore (#isRunning = false)
134			SwingUtilities.invokeLater(new Runnable() {
135			@Override
136			public void run() {
137			mapPane.onRenderingCompleted();
138			};
139			});
140	alfonx	530	} finally {
141			renderer.removeRenderListener(this);
142			}
143	alfonx	529	}
144	alfonx	530
145	alfonx	529	@Override
146			public void errorOccurred(Exception e) {
147	alfonx	530	// System.out.println("rendering error");
148	alfonx	529	mapPane.onRenderingFailed(e);
149			}
150	alfonx	510
151	alfonx	529	@Override
152			public void featureRenderer(SimpleFeature feature) {
153			}
154	alfonx	510
155	alfonx	530	}
156
157	alfonx	532	/**
158			* Ask to stop the rendering. May be called often.
159			*/
160	alfonx	529	public void cancelTask() {
161	alfonx	530	if (renderThread != null && renderThread.isAlive()) {
162			// System.out.println("request stop for thread " +task.getName());
163			renderThread.getRenderer().stopRendering();
164	alfonx	529	}
165			}
166	alfonx	510
167	alfonx	532	/**
168			* @return <code>true</code> if the {@link Thread} is busy rendering.
169			*/
170	alfonx	529	public boolean isRunning() {
171	alfonx	530	// if (task != null)
172			// System.out.println("is running "+task.getName()+" = true");
173			return (renderThread != null && renderThread.isAlive());
174	alfonx	529	}
175	alfonx	510
176	alfonx	532	/**
177			* Will stop rendering and remove the reference to the {@link Thread}.
178			*/
179	alfonx	529	public void dispose() {
180	alfonx	530	if (renderThread != null) {
181			renderThread.renderer.stopRendering();
182			renderThread = null;
183	alfonx	529	}
184			}
185	alfonx	510
186			}