| /******************************************************************************* |
| * Copyright (c) 2006 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| |
| package org.eclipse.swt.examples.graphics; |
| |
| import org.eclipse.swt.*; |
| import org.eclipse.swt.graphics.*; |
| import org.eclipse.swt.layout.*; |
| import org.eclipse.swt.widgets.*; |
| |
| /** |
| * This tab demonstrates the use of alpha blending. It allows a user to specify |
| * a custom alpha value. |
| */ |
| public class CustomAlphaTab extends AnimatedGraphicsTab { |
| |
| private Spinner alphaSpinner; |
| private Button colorButton; |
| private GraphicsBackground background; |
| private Menu menu; |
| private int angle; |
| |
| public CustomAlphaTab(GraphicsExample example) { |
| super(example); |
| } |
| |
| public String getCategory() { |
| return GraphicsExample.getResourceString("Alpha"); //$NON-NLS-1$ |
| } |
| |
| public String getText() { |
| return GraphicsExample.getResourceString("CustomAlpha"); //$NON-NLS-1$ |
| } |
| |
| public String getDescription() { |
| return GraphicsExample.getResourceString("CustomAlphaDescription"); //$NON-NLS-1$ |
| } |
| |
| public void dispose() { |
| if (menu != null) { |
| menu.dispose(); |
| menu = null; |
| } |
| } |
| |
| /** |
| * Creates the widgets used to control the drawing. |
| */ |
| public void createControlPanel(Composite parent) { |
| super.createControlPanel(parent); |
| |
| // create drop down combo for choosing clipping |
| Composite comp; |
| |
| // create spinner for line width |
| comp = new Composite(parent, SWT.NONE); |
| comp.setLayout(new GridLayout(2, false)); |
| new Label(comp, SWT.CENTER).setText(GraphicsExample |
| .getResourceString("Alpha")); //$NON-NLS-1$ |
| alphaSpinner = new Spinner(comp, SWT.BORDER | SWT.WRAP); |
| alphaSpinner.setMinimum(0); |
| alphaSpinner.setMaximum(255); |
| alphaSpinner.setSelection(127); |
| alphaSpinner.addListener(SWT.Selection, new Listener() { |
| public void handleEvent(Event event) { |
| example.redraw(); |
| } |
| }); |
| |
| // color menu |
| ColorMenu cm = new ColorMenu(); |
| cm.setPatternItems(example.checkAdvancedGraphics()); |
| menu = cm.createMenu(parent.getParent(), new ColorListener() { |
| public void setColor(GraphicsBackground 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 |
| 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, new Listener() { |
| public void handleEvent(Event event) { |
| final Button button = (Button) event.widget; |
| final Composite parent = button.getParent(); |
| Rectangle bounds = button.getBounds(); |
| Point point = parent.toDisplay(new Point(bounds.x, bounds.y)); |
| menu.setLocation(point.x, point.y + bounds.height); |
| menu.setVisible(true); |
| } |
| }); |
| } |
| |
| public void next(int width, int height) { |
| |
| angle = (angle+1)%360; |
| } |
| |
| public void paint(GC gc, int width, int height) { |
| if (!example.checkAdvancedGraphics()) return; |
| Device device = gc.getDevice(); |
| |
| 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.setAntialias(SWT.ON); |
| gc.setAlpha(alphaSpinner.getSelection()); |
| |
| // rotate on center |
| Transform transform = new Transform(device); |
| transform.translate(width/2, height/2); |
| transform.rotate(-angle); |
| transform.translate(-width/2, -height/2); |
| gc.setTransform(transform); |
| transform.dispose(); |
| |
| // choose the smallest between height and width |
| int diameter = (height < width) ? height : width; |
| |
| Path path = new Path(device); |
| path.addArc((width-diameter/5)/2, (height-diameter/5)/2, diameter/5, diameter/5, 0, 360); |
| path.addArc(5*(width-diameter/8)/12, 4*(height-diameter/8)/12, diameter/8, diameter/8, 0, 360); |
| path.addArc(7*(width-diameter/8)/12, 8*(height-diameter/8)/12, diameter/8, diameter/8, 0, 360); |
| path.addArc(6*(width-diameter/12)/12, 3*(height-diameter/12)/12, diameter/12, diameter/12, 0, 360); |
| path.addArc(6*(width-diameter/12)/12, 9*(height-diameter/12)/12, diameter/12, diameter/12, 0, 360); |
| path.addArc(11.5f*(width-diameter/18)/20, 5*(height-diameter/18)/18, diameter/18, diameter/18, 0, 360); |
| path.addArc(8.5f*(width-diameter/18)/20, 13*(height-diameter/18)/18, diameter/18, diameter/18, 0, 360); |
| path.addArc(62f*(width-diameter/25)/100, 32*(height-diameter/25)/100, diameter/25, diameter/25, 0, 360); |
| path.addArc(39f*(width-diameter/25)/100, 67*(height-diameter/25)/100, diameter/25, diameter/25, 0, 360); |
| |
| gc.fillPath(path); |
| path.dispose(); |
| |
| if (pattern != null) pattern.dispose(); |
| } |
| } |