/*******************************************************************************
* Copyright (c) 2000, 2005 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.draw2d.geometry;
/**
* Provides support for transformations of scaling, translation and rotation.
*/
public class Transform {
private double
scaleX = 1.0,
scaleY = 1.0,
dx, dy,
cos = 1.0,
sin;
/**
* Sets the value for the amount of scaling to be done along both axes.
*
* @param scale Scale factor
* @since 2.0
*/
public void setScale(double scale) {
scaleX = scaleY = scale;
}
/**
* Sets the value for the amount of scaling to be done along X and Y axes
* individually.
*
* @param x Amount of scaling on X axis
* @param y Amount of scaling on Y axis
* @since 2.0
*/
public void setScale(double x, double y) {
scaleX = x;
scaleY = y;
}
/**
* Sets the rotation angle.
*
* @param angle Angle of rotation
* @since 2.0
*/
public void setRotation(double angle) {
cos = Math.cos(angle);
sin = Math.sin(angle);
}
/**
* Sets the translation amounts for both axes.
*
* @param x Amount of shift on X axis
* @param y Amount of shift on Y axis
* @since 2.0
*/
public void setTranslation(double x, double y) {
dx = x;
dy = y;
}
/**
* Returns a new transformed Point of the input Point based on the transformation
* values set.
*
* @param p Point being transformed
* @return The transformed Point
* @since 2.0
*/
public Point getTransformed(Point p) {
double x = p.x;
double y = p.y;
double temp;
x *= scaleX;
y *= scaleY;
temp = x * cos - y * sin;
y = x * sin + y * cos;
x = temp;
return new Point(Math.round(x + dx), Math.round(y + dy));
}
}