examples/org.eclipse.swt.examples/src/org/eclipse/swt/examples/graphics/CurvesTab.java - platform/eclipse.platform.swt - Git at Google

 /*******************************************************************************
  * 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.events.*;
 import org.eclipse.swt.graphics.*;
 import org.eclipse.swt.widgets.*;

 /**
  * This tab presents cubic and quadratic curves that can be drawn.
  * The user may reposition the cubic and quadratic handles.
  */
 public class CurvesTab extends GraphicsTab {
 	/** These rectangles represent the handles on the curves. */
 	private Rectangle quadHndl, quadEndHndl, cubHndl1, cubHndl2, cubEndHndl;

 	/** These values represent the positions of the curves. */
 	private float quadXPos, quadYPos, cubXPos, cubYPos;

 	/** These values represent the x and y displacement of each handle. */
 	private float quadDiffX, quadDiffY, quadEndDiffX, quadEndDiffY;
 	private float cubDiffX1, cubDiffY1, cubDiffX2, cubDiffY2, cubEndDiffX, cubEndDiffY;

 	/** These are flags that indicate whether or not a handle has been moved. */
 	private boolean quadPtMoved, quadEndPtMoved, cubPt1Moved, cubPt2Moved, cubEndPtMoved;

 	private MouseMoveListener mouseMoveListener;
 	private MouseListener mouseListener;
 	private Cursor cursor;

 	/** true if hovering over a handle, false otherwise */
 	private boolean hovering = false;

 	/** true if left mouse button is held down, false otherwise */
 	private boolean mouseDown = false;


 public CurvesTab(GraphicsExample example) {
 	super(example);
 	quadHndl = new Rectangle(200, 150, 5, 5);
 	quadEndHndl = new Rectangle(400, 0, 5, 5);
 	quadDiffX = quadDiffY = quadEndDiffX = quadEndDiffY = 0;
 	cubHndl1 = new Rectangle(133, -60, 5, 5);
 	cubHndl2 = new Rectangle(266, 60, 5, 5);
 	cubDiffX1 = cubDiffY1 = cubDiffX2 = cubDiffY2 = 0;
 	cubEndHndl = new Rectangle(400, 0, 5, 5);
 	cubEndDiffX = cubEndDiffY = 0;
 }

 public String getCategory() {
 	return GraphicsExample.getResourceString("Curves"); //$NON-NLS-1$
 }

 public String getText() {
 	return GraphicsExample.getResourceString("Curves"); //$NON-NLS-1$
 }

 public String getDescription() {
 	return GraphicsExample.getResourceString("CurvesDescription"); //$NON-NLS-1$
 }

 public boolean getDoubleBuffered() {
 	return true;
 }

 public void dispose() {
 	if (mouseListener != null)
 		example.canvas.removeMouseListener(mouseListener);

 	if (mouseMoveListener != null)
 		example.canvas.removeMouseMoveListener(mouseMoveListener);

 	if (cursor != null) {
 		cursor.dispose();
 		cursor = null;
 	}
 }

 /**
  * This helper method determines whether or not the cursor is positioned
  * over a handle.
  *
  * @param e
  *            A MouseEvent
  * @return true if cursor is positioned over a handle; false otherwise
  */
 private boolean isHovering(MouseEvent e) {
 	Rectangle quad = new Rectangle(quadHndl.x + (int)quadXPos - 1, quadHndl.y + (int)quadYPos - 1, quadHndl.width+2, quadHndl.height+2);
 	Rectangle quadEnd = new Rectangle(quadEndHndl.x + (int)quadXPos - 1, quadEndHndl.y + (int)quadYPos - 1, quadEndHndl.width+2, quadEndHndl.height+2);
 	Rectangle cub1 = new Rectangle(cubHndl1.x + (int)cubXPos - 1, cubHndl1.y + (int)cubYPos - 1, cubHndl1.width+2, cubHndl1.height+2);
 	Rectangle cub2 = new Rectangle(cubHndl2.x + (int)cubXPos - 1, cubHndl2.y + (int)cubYPos - 1, cubHndl2.width+2, cubHndl2.height+2);
 	Rectangle cubEnd = new Rectangle(cubEndHndl.x + (int)cubXPos - 1, cubEndHndl.y + (int)cubYPos - 1, cubEndHndl.width+2, cubEndHndl.height+2);

 	return ( quad.contains(e.x, e.y) || quadEnd.contains(e.x, e.y)
 		 || cub1.contains(e.x, e.y) || cub2.contains(e.x, e.y)
 		 || cubEnd.contains(e.x, e.y));
 }
 /**
  * Creates the widgets used to control the drawing.
  */
 public void createControlPanel(Composite parent) {
 	if (cursor == null) {
 		cursor = new Cursor(parent.getDisplay(), SWT.CURSOR_HAND);
 	}

 	mouseMoveListener = new MouseMoveListener() {

 		public void mouseMove(MouseEvent e) {
 			if (hovering && mouseDown) {
 				example.canvas.setCursor(cursor);
 			} else if (isHovering(e)) {
 				example.canvas.setCursor(cursor);
 				hovering = true;
 			} else {
 				example.canvas.setCursor(null);
 				hovering = false;
 			}

 			if (quadPtMoved) {
 				quadDiffX = quadDiffX + e.x - (int)quadXPos - quadHndl.x;
 				quadDiffY = quadDiffY + e.y - (int)quadYPos - quadHndl.y;
 				quadHndl.x = e.x - (int)quadXPos;
 				quadHndl.y = e.y - (int)quadYPos;
 			} else if (quadEndPtMoved) {
 				quadEndDiffX = quadEndDiffX + e.x - (int)quadXPos - quadEndHndl.x;
 				quadEndDiffY = quadEndDiffY + e.y - (int)quadYPos - quadEndHndl.y;
 				quadEndHndl.x = e.x - (int)quadXPos;
 				quadEndHndl.y = e.y - (int)quadYPos;
 			} else if (cubPt1Moved) {
 				cubDiffX1 = cubDiffX1 + e.x - (int)cubXPos - cubHndl1.x;
 				cubDiffY1 = cubDiffY1 + e.y - (int)cubYPos - cubHndl1.y;
 				cubHndl1.x = e.x - (int)cubXPos;
 				cubHndl1.y = e.y - (int)cubYPos;
 			} else if (cubPt2Moved) {
 				cubDiffX2 = cubDiffX2 + e.x - (int)cubXPos - cubHndl2.x;
 				cubDiffY2 = cubDiffY2 + e.y - (int)cubYPos - cubHndl2.y;
 				cubHndl2.x = e.x - (int)cubXPos;
 				cubHndl2.y = e.y - (int)cubYPos;
 			} else if (cubEndPtMoved) {
 				cubEndDiffX = cubEndDiffX + e.x - (int)cubXPos - cubEndHndl.x;
 				cubEndDiffY = cubEndDiffY + e.y - (int)cubYPos - cubEndHndl.y;
 				cubEndHndl.x = e.x - (int)cubXPos;
 				cubEndHndl.y = e.y - (int)cubYPos;
 			}
 			example.redraw();
 		}
 	};

 	mouseListener = new MouseListener() {

 		public void mouseDoubleClick(MouseEvent e) {}

 		/**
 		 * Sent when a mouse button is pressed.
 		 *
 		 * @param e an event containing information about the mouse button press
 		 */
 		public void mouseDown(MouseEvent e) {
 			Rectangle quad = new Rectangle(quadHndl.x + (int)quadXPos - 1, quadHndl.y + (int)quadYPos - 1, quadHndl.width+2, quadHndl.height+2);
 			Rectangle quadEnd = new Rectangle(quadEndHndl.x + (int)quadXPos - 1, quadEndHndl.y + (int)quadYPos - 1, quadEndHndl.width+2, quadEndHndl.height+2);
 			Rectangle cub1 = new Rectangle(cubHndl1.x + (int)cubXPos - 1, cubHndl1.y + (int)cubYPos - 1, cubHndl1.width+2, cubHndl1.height+2);
 			Rectangle cub2 = new Rectangle(cubHndl2.x + (int)cubXPos - 1, cubHndl2.y + (int)cubYPos - 1, cubHndl2.width+2, cubHndl2.height+2);
 			Rectangle cubEnd = new Rectangle(cubEndHndl.x + (int)cubXPos - 1, cubEndHndl.y + (int)cubYPos - 1, cubEndHndl.width+2, cubEndHndl.height+2);

 			if (quad.contains(e.x, e.y)) {
 				quadPtMoved = true;
 				mouseDown = true;
 			} else if (quadEnd.contains(e.x, e.y)) {
 				quadEndPtMoved = true;
 				mouseDown = true;
 			} else if (cub1.contains(e.x, e.y)) {
 				cubPt1Moved = true;
 				mouseDown = true;
 			} else if (cub2.contains(e.x, e.y)) {
 				cubPt2Moved = true;
 				mouseDown = true;
 			} else if (cubEnd.contains(e.x, e.y)) {
 				cubEndPtMoved = true;
 				mouseDown = true;
 			}
 		}

 		/**
 		 * Sent when a mouse button is released.
 		 *
 		 * @param e an event containing information about the mouse button release
 		 */
 		public void mouseUp(MouseEvent e) {
 			mouseDown = false;
 			if (isHovering(e)) {
 				example.canvas.setCursor(cursor);
 			} else {
 				example.canvas.setCursor(null);
 			}

 			if (quadPtMoved)
 				quadPtMoved = false;
 			if (quadEndPtMoved)
 				quadEndPtMoved = false;
 			if (cubPt1Moved)
 				cubPt1Moved = false;
 			if (cubPt2Moved)
 				cubPt2Moved = false;
 			if (cubEndPtMoved)
 				cubEndPtMoved = false;

 			example.redraw();
 		}
 	};
 	example.canvas.addMouseMoveListener(mouseMoveListener);
 	example.canvas.addMouseListener(mouseListener);
 }

 public void paint(GC gc, int width, int height) {
 	if (!example.checkAdvancedGraphics()) return;
 	Device device = gc.getDevice();

 	Font font = new Font(device, getPlatformFont(), 16, SWT.ITALIC);
 	gc.setFont(font);
 	gc.setLineWidth(5);

 	Transform transform;

 	// ----- cubic curve -----
 	cubXPos = width/5;
 	cubYPos = height/3;

 	transform = new Transform(device);
 	transform.translate(cubXPos, cubYPos);
 	gc.setTransform(transform);
 	transform.dispose();

 	gc.setForeground(device.getSystemColor(SWT.COLOR_RED));
 	gc.drawString(GraphicsExample.getResourceString("Cubic"), 25, -70, true);

 	Path path = new Path(device);
 	path.cubicTo(133 + cubDiffX1, -60 + cubDiffY1, 266 + cubDiffX2, 60 + cubDiffY2, 400 + cubEndDiffX, 0 + cubEndDiffY);
 	gc.drawPath(path);
 	path.dispose();

 	gc.setTransform(null);
 	gc.setForeground(device.getSystemColor(SWT.COLOR_DARK_BLUE));
 	gc.drawRectangle(cubHndl1.x + (int)cubXPos, cubHndl1.y + (int)cubYPos, cubHndl1.width, cubHndl1.height);
 	gc.drawRectangle(cubHndl2.x + (int)cubXPos, cubHndl2.y + (int)cubYPos, cubHndl2.width, cubHndl2.height);
 	gc.drawRectangle(cubEndHndl.x + (int)cubXPos, cubEndHndl.y + (int)cubYPos, cubEndHndl.width, cubEndHndl.height);

 	// ----- quadratic curve -----
 	quadXPos = width/5;
 	quadYPos = 2*height/3;

 	transform = new Transform(device);
 	transform.translate(quadXPos, quadYPos);
 	gc.setTransform(transform);
 	transform.dispose();

 	gc.setForeground(device.getSystemColor(SWT.COLOR_GREEN));
 	gc.drawString(GraphicsExample.getResourceString("Quadratic"), 0, -50, true);

 	path = new Path(device);
 	path.quadTo(200 + quadDiffX, 150 + quadDiffY, 400 + quadEndDiffX, 0 + quadEndDiffY);
 	gc.drawPath(path);
 	path.dispose();

 	gc.setTransform(null);
 	gc.setForeground(device.getSystemColor(SWT.COLOR_GRAY));
 	gc.drawRectangle(quadHndl.x + (int)quadXPos, quadHndl.y + (int)quadYPos, quadHndl.width, quadHndl.height);
 	gc.drawRectangle(quadEndHndl.x + (int)quadXPos, quadEndHndl.y + (int)quadYPos, quadEndHndl.width, quadEndHndl.height);

 	font.dispose();
 }

 /**
  * Returns the name of a valid font for the resident platform.
  */
 static String getPlatformFont() {
 	if(SWT.getPlatform() == "win32") {
 		return "Arial";
 	} else if (SWT.getPlatform() == "motif") {
 		return "Helvetica";
 	} else if (SWT.getPlatform() == "gtk") {
 		return "Baekmuk Batang";
 	} else if (SWT.getPlatform() == "carbon") {
 		return "Arial";
 	} else { // photon, etc ...
 		return "Verdana";
 	}
 }

 }
	/*******************************************************************************
	* 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.events.*;
	import org.eclipse.swt.graphics.*;
	import org.eclipse.swt.widgets.*;

	/**
	* This tab presents cubic and quadratic curves that can be drawn.
	* The user may reposition the cubic and quadratic handles.
	*/
	public class CurvesTab extends GraphicsTab {
	/** These rectangles represent the handles on the curves. */
	private Rectangle quadHndl, quadEndHndl, cubHndl1, cubHndl2, cubEndHndl;

	/** These values represent the positions of the curves. */
	private float quadXPos, quadYPos, cubXPos, cubYPos;

	/** These values represent the x and y displacement of each handle. */
	private float quadDiffX, quadDiffY, quadEndDiffX, quadEndDiffY;
	private float cubDiffX1, cubDiffY1, cubDiffX2, cubDiffY2, cubEndDiffX, cubEndDiffY;

	/** These are flags that indicate whether or not a handle has been moved. */
	private boolean quadPtMoved, quadEndPtMoved, cubPt1Moved, cubPt2Moved, cubEndPtMoved;

	private MouseMoveListener mouseMoveListener;
	private MouseListener mouseListener;
	private Cursor cursor;

	/** true if hovering over a handle, false otherwise */
	private boolean hovering = false;

	/** true if left mouse button is held down, false otherwise */
	private boolean mouseDown = false;


	public CurvesTab(GraphicsExample example) {
	super(example);
	quadHndl = new Rectangle(200, 150, 5, 5);
	quadEndHndl = new Rectangle(400, 0, 5, 5);
	quadDiffX = quadDiffY = quadEndDiffX = quadEndDiffY = 0;
	cubHndl1 = new Rectangle(133, -60, 5, 5);
	cubHndl2 = new Rectangle(266, 60, 5, 5);
	cubDiffX1 = cubDiffY1 = cubDiffX2 = cubDiffY2 = 0;
	cubEndHndl = new Rectangle(400, 0, 5, 5);
	cubEndDiffX = cubEndDiffY = 0;
	}

	public String getCategory() {
	return GraphicsExample.getResourceString("Curves"); //$NON-NLS-1$
	}

	public String getText() {
	return GraphicsExample.getResourceString("Curves"); //$NON-NLS-1$
	}

	public String getDescription() {
	return GraphicsExample.getResourceString("CurvesDescription"); //$NON-NLS-1$
	}

	public boolean getDoubleBuffered() {
	return true;
	}

	public void dispose() {
	if (mouseListener != null)
	example.canvas.removeMouseListener(mouseListener);

	if (mouseMoveListener != null)
	example.canvas.removeMouseMoveListener(mouseMoveListener);

	if (cursor != null) {
	cursor.dispose();
	cursor = null;
	}
	}

	/**
	* This helper method determines whether or not the cursor is positioned
	* over a handle.
	*
	* @param e
	* A MouseEvent
	* @return true if cursor is positioned over a handle; false otherwise
	*/
	private boolean isHovering(MouseEvent e) {
	Rectangle quad = new Rectangle(quadHndl.x + (int)quadXPos - 1, quadHndl.y + (int)quadYPos - 1, quadHndl.width+2, quadHndl.height+2);
	Rectangle quadEnd = new Rectangle(quadEndHndl.x + (int)quadXPos - 1, quadEndHndl.y + (int)quadYPos - 1, quadEndHndl.width+2, quadEndHndl.height+2);
	Rectangle cub1 = new Rectangle(cubHndl1.x + (int)cubXPos - 1, cubHndl1.y + (int)cubYPos - 1, cubHndl1.width+2, cubHndl1.height+2);
	Rectangle cub2 = new Rectangle(cubHndl2.x + (int)cubXPos - 1, cubHndl2.y + (int)cubYPos - 1, cubHndl2.width+2, cubHndl2.height+2);
	Rectangle cubEnd = new Rectangle(cubEndHndl.x + (int)cubXPos - 1, cubEndHndl.y + (int)cubYPos - 1, cubEndHndl.width+2, cubEndHndl.height+2);

	return ( quad.contains(e.x, e.y) \|\| quadEnd.contains(e.x, e.y)
	\|\| cub1.contains(e.x, e.y) \|\| cub2.contains(e.x, e.y)
	\|\| cubEnd.contains(e.x, e.y));
	}
	/**
	* Creates the widgets used to control the drawing.
	*/
	public void createControlPanel(Composite parent) {
	if (cursor == null) {
	cursor = new Cursor(parent.getDisplay(), SWT.CURSOR_HAND);
	}

	mouseMoveListener = new MouseMoveListener() {

	public void mouseMove(MouseEvent e) {
	if (hovering && mouseDown) {
	example.canvas.setCursor(cursor);
	} else if (isHovering(e)) {
	example.canvas.setCursor(cursor);
	hovering = true;
	} else {
	example.canvas.setCursor(null);
	hovering = false;
	}

	if (quadPtMoved) {
	quadDiffX = quadDiffX + e.x - (int)quadXPos - quadHndl.x;
	quadDiffY = quadDiffY + e.y - (int)quadYPos - quadHndl.y;
	quadHndl.x = e.x - (int)quadXPos;
	quadHndl.y = e.y - (int)quadYPos;
	} else if (quadEndPtMoved) {
	quadEndDiffX = quadEndDiffX + e.x - (int)quadXPos - quadEndHndl.x;
	quadEndDiffY = quadEndDiffY + e.y - (int)quadYPos - quadEndHndl.y;
	quadEndHndl.x = e.x - (int)quadXPos;
	quadEndHndl.y = e.y - (int)quadYPos;
	} else if (cubPt1Moved) {
	cubDiffX1 = cubDiffX1 + e.x - (int)cubXPos - cubHndl1.x;
	cubDiffY1 = cubDiffY1 + e.y - (int)cubYPos - cubHndl1.y;
	cubHndl1.x = e.x - (int)cubXPos;
	cubHndl1.y = e.y - (int)cubYPos;
	} else if (cubPt2Moved) {
	cubDiffX2 = cubDiffX2 + e.x - (int)cubXPos - cubHndl2.x;
	cubDiffY2 = cubDiffY2 + e.y - (int)cubYPos - cubHndl2.y;
	cubHndl2.x = e.x - (int)cubXPos;
	cubHndl2.y = e.y - (int)cubYPos;
	} else if (cubEndPtMoved) {
	cubEndDiffX = cubEndDiffX + e.x - (int)cubXPos - cubEndHndl.x;
	cubEndDiffY = cubEndDiffY + e.y - (int)cubYPos - cubEndHndl.y;
	cubEndHndl.x = e.x - (int)cubXPos;
	cubEndHndl.y = e.y - (int)cubYPos;
	}
	example.redraw();
	}
	};

	mouseListener = new MouseListener() {

	public void mouseDoubleClick(MouseEvent e) {}

	/**
	* Sent when a mouse button is pressed.
	*
	* @param e an event containing information about the mouse button press
	*/
	public void mouseDown(MouseEvent e) {
	Rectangle quad = new Rectangle(quadHndl.x + (int)quadXPos - 1, quadHndl.y + (int)quadYPos - 1, quadHndl.width+2, quadHndl.height+2);
	Rectangle quadEnd = new Rectangle(quadEndHndl.x + (int)quadXPos - 1, quadEndHndl.y + (int)quadYPos - 1, quadEndHndl.width+2, quadEndHndl.height+2);
	Rectangle cub1 = new Rectangle(cubHndl1.x + (int)cubXPos - 1, cubHndl1.y + (int)cubYPos - 1, cubHndl1.width+2, cubHndl1.height+2);
	Rectangle cub2 = new Rectangle(cubHndl2.x + (int)cubXPos - 1, cubHndl2.y + (int)cubYPos - 1, cubHndl2.width+2, cubHndl2.height+2);
	Rectangle cubEnd = new Rectangle(cubEndHndl.x + (int)cubXPos - 1, cubEndHndl.y + (int)cubYPos - 1, cubEndHndl.width+2, cubEndHndl.height+2);

	if (quad.contains(e.x, e.y)) {
	quadPtMoved = true;
	mouseDown = true;
	} else if (quadEnd.contains(e.x, e.y)) {
	quadEndPtMoved = true;
	mouseDown = true;
	} else if (cub1.contains(e.x, e.y)) {
	cubPt1Moved = true;
	mouseDown = true;
	} else if (cub2.contains(e.x, e.y)) {
	cubPt2Moved = true;
	mouseDown = true;
	} else if (cubEnd.contains(e.x, e.y)) {
	cubEndPtMoved = true;
	mouseDown = true;
	}
	}

	/**
	* Sent when a mouse button is released.
	*
	* @param e an event containing information about the mouse button release
	*/
	public void mouseUp(MouseEvent e) {
	mouseDown = false;
	if (isHovering(e)) {
	example.canvas.setCursor(cursor);
	} else {
	example.canvas.setCursor(null);
	}

	if (quadPtMoved)
	quadPtMoved = false;
	if (quadEndPtMoved)
	quadEndPtMoved = false;
	if (cubPt1Moved)
	cubPt1Moved = false;
	if (cubPt2Moved)
	cubPt2Moved = false;
	if (cubEndPtMoved)
	cubEndPtMoved = false;

	example.redraw();
	}
	};
	example.canvas.addMouseMoveListener(mouseMoveListener);
	example.canvas.addMouseListener(mouseListener);
	}

	public void paint(GC gc, int width, int height) {
	if (!example.checkAdvancedGraphics()) return;
	Device device = gc.getDevice();

	Font font = new Font(device, getPlatformFont(), 16, SWT.ITALIC);
	gc.setFont(font);
	gc.setLineWidth(5);

	Transform transform;

	// ----- cubic curve -----
	cubXPos = width/5;
	cubYPos = height/3;

	transform = new Transform(device);
	transform.translate(cubXPos, cubYPos);
	gc.setTransform(transform);
	transform.dispose();

	gc.setForeground(device.getSystemColor(SWT.COLOR_RED));
	gc.drawString(GraphicsExample.getResourceString("Cubic"), 25, -70, true);

	Path path = new Path(device);
	path.cubicTo(133 + cubDiffX1, -60 + cubDiffY1, 266 + cubDiffX2, 60 + cubDiffY2, 400 + cubEndDiffX, 0 + cubEndDiffY);
	gc.drawPath(path);
	path.dispose();

	gc.setTransform(null);
	gc.setForeground(device.getSystemColor(SWT.COLOR_DARK_BLUE));
	gc.drawRectangle(cubHndl1.x + (int)cubXPos, cubHndl1.y + (int)cubYPos, cubHndl1.width, cubHndl1.height);
	gc.drawRectangle(cubHndl2.x + (int)cubXPos, cubHndl2.y + (int)cubYPos, cubHndl2.width, cubHndl2.height);
	gc.drawRectangle(cubEndHndl.x + (int)cubXPos, cubEndHndl.y + (int)cubYPos, cubEndHndl.width, cubEndHndl.height);

	// ----- quadratic curve -----
	quadXPos = width/5;
	quadYPos = 2*height/3;

	transform = new Transform(device);
	transform.translate(quadXPos, quadYPos);
	gc.setTransform(transform);
	transform.dispose();

	gc.setForeground(device.getSystemColor(SWT.COLOR_GREEN));
	gc.drawString(GraphicsExample.getResourceString("Quadratic"), 0, -50, true);

	path = new Path(device);
	path.quadTo(200 + quadDiffX, 150 + quadDiffY, 400 + quadEndDiffX, 0 + quadEndDiffY);
	gc.drawPath(path);
	path.dispose();

	gc.setTransform(null);
	gc.setForeground(device.getSystemColor(SWT.COLOR_GRAY));
	gc.drawRectangle(quadHndl.x + (int)quadXPos, quadHndl.y + (int)quadYPos, quadHndl.width, quadHndl.height);
	gc.drawRectangle(quadEndHndl.x + (int)quadXPos, quadEndHndl.y + (int)quadYPos, quadEndHndl.width, quadEndHndl.height);

	font.dispose();
	}

	/**
	* Returns the name of a valid font for the resident platform.
	*/
	static String getPlatformFont() {
	if(SWT.getPlatform() == "win32") {
	return "Arial";
	} else if (SWT.getPlatform() == "motif") {
	return "Helvetica";
	} else if (SWT.getPlatform() == "gtk") {
	return "Baekmuk Batang";
	} else if (SWT.getPlatform() == "carbon") {
	return "Arial";
	} else { // photon, etc ...
	return "Verdana";
	}
	}

	}