/*
* Open Source Physics software is free software as described near the bottom of this code file.
*
* For additional information and documentation on Open Source Physics please see:
* <http://www.opensourcephysics.org/>
*/
/*
* The org.opensourcephysics.media.core package defines the Open Source Physics
* media framework for working with video and other media.
*
* Copyright (c) 2014 Douglas Brown and Wolfgang Christian.
*
* This is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston MA 02111-1307 USA
* or view the license online at http://www.gnu.org/copyleft/gpl.html
*
* For additional information and documentation on Open Source Physics,
* please see <http://www.opensourcephysics.org/>.
*/
package org.opensourcephysics.media.core;
import java.awt.BasicStroke;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Shape;
import java.awt.geom.AffineTransform;
import java.awt.geom.GeneralPath;
import java.awt.geom.Line2D;
import org.opensourcephysics.display.DrawingPanel;
import org.opensourcephysics.display.Interactive;
/**
* This is a TShape that draws a vector.
*
* @author Douglas Brown
* @version 1.0
*/
public class TVector extends TShape {
// instance fields
protected GeneralPath path = new GeneralPath();
protected Line2D line = new Line2D.Double();
protected Shape head;
protected Shape shaft;
protected int length = 16;
protected int width = 4;
protected AffineTransform rotation = new AffineTransform();
protected TPoint tail = new LineEnd();
protected TPoint tip = new LineEnd();
protected Rectangle tipRect = new Rectangle(0, 0, 8, 8);
protected boolean tipEnabled = true;
/**
* Constructs a default TVector with tail position (0, 0) and
* components (0, 0).
*/
public TVector() {
setStroke(new BasicStroke(1));
}
/**
* Constructs a TVector with specified tail and components.
*
* @param xt x position of tail
* @param yt y position of tail
* @param xc x component
* @param yc y component
*/
public TVector(double xt, double yt, double xc, double yc) {
tail.setXY(xt, yt);
tip.setXY(xt+xc, yt+yc);
setStroke(new BasicStroke(1));
}
/**
* Gets the tip.
*
* @return the tip
*/
public TPoint getTip() {
return tip;
}
/**
* Gets the tail.
*
* @return the tail
*/
public TPoint getTail() {
return tail;
}
/**
* Sets the x component.
*
* @param x the x component
*/
public void setXComponent(double x) {
tip.setX(tail.getX()+x);
}
/**
* Sets the y component.
*
* @param y the y component
*/
public void setYComponent(double y) {
tip.setY(tail.getY()+y);
}
/**
* Sets the x and y components.
*
* @param x the x component
* @param y the y component
*/
public void setXYComponents(double x, double y) {
tip.setXY(tail.getX()+x, tail.getY()+y);
}
/**
* Gets the x component.
*
* @return the x component
*/
public double getXComponent() {
return tip.getX()-tail.getX();
}
/**
* Gets the y component.
*
* @return the y component
*/
public double getYComponent() {
return tip.getY()-tail.getY();
}
/**
* Overrides TPoint setXY method to move both tip and tail.
*
* @param x the x position
* @param y the y position
*/
public void setXY(double x, double y) {
double dx = x-getX();
double dy = y-getY();
tip.translate(dx, dy);
tail.translate(dx, dy);
}
/**
* Enables and disables the interactivity of the tip.
*
* @param enabled <code>true</code> to enable the tip
*/
public void setTipEnabled(boolean enabled) {
tipEnabled = enabled;
}
/**
* Gets whether the tip is enabled.
*
* @return <code>true</code> if the tip is enabled
*/
public boolean isTipEnabled() {
return tipEnabled;
}
/**
* Sets the length of the arrow tip.
*
* @param tipLength the tip length in pixels
*/
public void setTipLength(int tipLength) {
tipLength = Math.max(8, tipLength);
width = tipLength/4;
length = 4*width;
}
/**
* Overrides TPoint setStroke method.
*
* @param stroke the desired stroke
*/
public void setStroke(BasicStroke stroke) {
if(stroke==null) {
return;
}
this.stroke = new BasicStroke(stroke.getLineWidth(), BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER, 8, stroke.getDashArray(), stroke.getDashPhase());
}
/**
* Returns the interactive drawable object at the specified pixel
* position.
*
* @param panel the drawing panel
* @param xpix the x pixel position on the panel
* @param ypix the y pixel position on the panel
* @return the interactive drawable object
*/
public Interactive findInteractive(DrawingPanel panel, int xpix, int ypix) {
if(!(panel instanceof VideoPanel)) {
return null;
}
if(!isEnabled()||!isVisible()) {
return null;
}
setHitRectCenter(xpix, ypix);
if((shaft!=null)&&shaft.intersects(hitRect)) {
return this;
}
if(tipEnabled&&(head!=null)&&head.intersects(hitRect)) {
return tip;
}
return null;
}
//________________________ protected methods ________________________
/**
* Gets the shape to be filled in the draw method.
*
* @param vidPanel the video panel
* @return the line shape
*/
protected Shape getShape(VideoPanel vidPanel) {
this.center(tip, tail);
Point p1 = tail.getScreenPosition(vidPanel); // tail
Point p2 = tip.getScreenPosition(vidPanel); // tip
// set up transform
double theta = Math.atan2(p2.y-p1.y, p2.x-p1.x);
rotation.setToRotation(theta, p1.x, p1.y);
rotation.translate(p1.x, p1.y);
// get line length d
float d = (float) p1.distance(p2);
// set up head hit shape usng full line length
path.reset();
path.moveTo(d-4, 0);
path.lineTo(d-6, -2);
path.lineTo(d, 0);
path.lineTo(d-6, 2);
path.closePath();
head = rotation.createTransformedShape(path);
// shorten line length to account for stroke width
// see Java 2D API Graphics, by VJ Hardy (Sun, 2000) page 147
float w = stroke.getLineWidth();
d = d-1.58f*w;
// set up shaft hit shape using shortened line length
line.setLine(0, 0, d-length, 0);
shaft = rotation.createTransformedShape(line);
// set up and return fill shape usng shortened line length
path.reset();
path.moveTo(0, 0);
path.lineTo(d-length+width, 0);
path.lineTo(d-length, -width);
path.lineTo(d, 0);
path.lineTo(d-length, width);
path.lineTo(d-length+width, 0);
Shape vector = rotation.createTransformedShape(path);
return stroke.createStrokedShape(vector);
}
//_________________________ inner End classes _________________________
class LineEnd extends TPoint {
/**
* Overrides TPoint getBounds method
*
* @param vidPanel the video panel
* @return the bounding rectangle
*/
public Rectangle getBounds(VideoPanel vidPanel) {
return TVector.this.getBounds(vidPanel);
}
/**
* Overrides TPoint getFrameNumber method
*
* @param vidPanel the video panel
* @return the frame number
*/
public int getFrameNumber(VideoPanel vidPanel) {
return TVector.this.getFrameNumber(vidPanel);
}
}
}
/*
* Open Source Physics software is free software; you can redistribute
* it and/or modify it under the terms of the GNU General Public License (GPL) as
* published by the Free Software Foundation; either version 2 of the License,
* or(at your option) any later version.
* Code that uses any portion of the code in the org.opensourcephysics package
* or any subpackage (subdirectory) of this package must must also be be released
* under the GNU GPL license.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston MA 02111-1307 USA
* or view the license online at http://www.gnu.org/copyleft/gpl.html
*
* Copyright (c) 2007 The Open Source Physics project
* http://www.opensourcephysics.org
*/