Java tutorial
/******************************************************************************* * Copyright (c) 2006, 2016 IBM Corporation and others. * * This program and the accompanying materials * are made available under the terms of the Eclipse Public License 2.0 * which accompanies this distribution, and is available at * https://www.eclipse.org/legal/epl-2.0/ * * SPDX-License-Identifier: EPL-2.0 * * Contributors: * IBM Corporation - initial API and implementation *******************************************************************************/ package org.eclipse.swt.examples.graphics; import org.eclipse.swt.SWT; import org.eclipse.swt.graphics.Device; import org.eclipse.swt.graphics.GC; import org.eclipse.swt.graphics.Path; import org.eclipse.swt.graphics.Pattern; import org.eclipse.swt.graphics.Point; import org.eclipse.swt.graphics.Rectangle; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Button; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Menu; /** * This is another tab that demonstrates the use of a path clipping. */ public class PathClippingAnimTab extends AnimatedGraphicsTab { private Button colorButton; private GraphicsBackground background; private Menu menu; private int rectWidth = 300; private int rectHeight = 300; private int incWidth = 5; private int incHeight = 5; private boolean vertical = false; private int angle; public PathClippingAnimTab(GraphicsExample example) { super(example); } @Override public String getCategory() { return GraphicsExample.getResourceString("Clipping"); //$NON-NLS-1$ } @Override public String getText() { return GraphicsExample.getResourceString("AnimPathClipping"); //$NON-NLS-1$ } @Override public String getDescription() { return GraphicsExample.getResourceString("AnimPathClippingDesc"); //$NON-NLS-1$ } @Override public void dispose() { if (menu != null) { menu.dispose(); menu = null; } } /** * Creates the widgets used to control the drawing. */ @Override public void createControlPanel(Composite parent) { super.createControlPanel(parent); // color menu ColorMenu cm = new ColorMenu(); cm.setPatternItems(example.checkAdvancedGraphics()); menu = cm.createMenu(parent.getParent(), gb -> { background = gb; colorButton.setImage(gb.getThumbNail()); example.redraw(); }); // initialize the background to the 5th item in the menu (blue) background = (GraphicsBackground) menu.getItem(4).getData(); // color button Composite comp = new Composite(parent, SWT.NONE); comp.setLayout(new GridLayout(2, false)); colorButton = new Button(comp, SWT.PUSH); colorButton.setText(GraphicsExample.getResourceString("Color")); //$NON-NLS-1$ colorButton.setImage(background.getThumbNail()); colorButton.addListener(SWT.Selection, event -> { final Button button = (Button) event.widget; final Composite parent1 = button.getParent(); Rectangle bounds = button.getBounds(); Point point = parent1.toDisplay(new Point(bounds.x, bounds.y)); menu.setLocation(point.x, point.y + bounds.height); menu.setVisible(true); }); } @Override public void next(int width, int height) { angle = (angle + 5) % 360; if (vertical) { if (rectHeight <= 0) { incHeight = -incHeight; } if (rectHeight >= height) { incHeight = -incHeight; vertical = false; } rectHeight = rectHeight + incHeight; } else { if (rectWidth <= 0) { incWidth = -incWidth; } if (rectWidth >= width) { incWidth = -incWidth; vertical = true; } rectWidth = rectWidth + incWidth; } } @Override public void paint(GC gc, int width, int height) { if (!example.checkAdvancedGraphics()) return; Device device = gc.getDevice(); // top triangle Path path = new Path(device); path.moveTo(width / 2, 0); path.lineTo(width / 2 + 100, 173); path.lineTo(width / 2 - 100, 173); path.lineTo(width / 2, 0); // bottom triangle Path path2 = new Path(device); path2.moveTo(width / 2, height); path2.lineTo(width / 2 + 100, height - 173); path2.lineTo(width / 2 - 100, height - 173); path2.lineTo(width / 2, height); // left triangle Path path3 = new Path(device); path3.moveTo(0, height / 2); path3.lineTo(173, height / 2 - 100); path3.lineTo(173, height / 2 + 100); path3.lineTo(0, height / 2); // right triangle Path path4 = new Path(device); path4.moveTo(width, height / 2); path4.lineTo(width - 173, height / 2 - 100); path4.lineTo(width - 173, height / 2 + 100); path4.lineTo(width, height / 2); // circle Path path5 = new Path(device); path5.moveTo((width - 200) / 2, (height - 200) / 2); path5.addArc((width - 200) / 2, (height - 200) / 2, 200, 200, 0, 360); // top rectangle Path path6 = new Path(device); path6.addRectangle((width - 40) / 2, 175, 40, ((height - 200) / 2) - 177); // bottom rectangle Path path7 = new Path(device); path7.addRectangle((width - 40) / 2, ((height - 200) / 2) + 202, 40, (height - 175) - (((height - 200) / 2) + 202)); // left rectangle Path path8 = new Path(device); path8.addRectangle(175, (height - 40) / 2, ((width - 200) / 2) - 177, 40); // right rectangle Path path9 = new Path(device); path9.addRectangle((width - 200) / 2 + 202, (height - 40) / 2, (width - 175) - ((width - 200) / 2 + 202), 40); path.addPath(path2); path.addPath(path3); path.addPath(path4); path.addPath(path5); path.addPath(path6); path.addPath(path7); path.addPath(path8); path.addPath(path9); gc.setClipping(path); Pattern pattern = null; if (background.getBgColor1() != null) { gc.setBackground(background.getBgColor1()); } else if (background.getBgImage() != null) { pattern = new Pattern(device, background.getBgImage()); gc.setBackgroundPattern(pattern); } gc.setLineWidth(2); gc.fillRectangle((width - rectWidth) / 2, (height - rectHeight) / 2, rectWidth, rectHeight); gc.drawPath(path); if (pattern != null) pattern.dispose(); path9.dispose(); path8.dispose(); path7.dispose(); path6.dispose(); path5.dispose(); path4.dispose(); path3.dispose(); path2.dispose(); path.dispose(); } }