package net.sf.openrocket.rocketcomponent;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import net.sf.openrocket.l10n.Translator;
import net.sf.openrocket.startup.Application;
import net.sf.openrocket.util.ArrayList;
import net.sf.openrocket.util.BugException;
import net.sf.openrocket.util.Coordinate;
public class FreeformFinSet extends FinSet {
private static final Logger log = LoggerFactory.getLogger(FreeformFinSet.class);
private static final Translator trans = Application.getTranslator();
private ArrayList<Coordinate> points = new ArrayList<Coordinate>();
public FreeformFinSet() {
points.add(Coordinate.NUL);
points.add(new Coordinate(0.025, 0.05));
points.add(new Coordinate(0.075, 0.05));
points.add(new Coordinate(0.05, 0));
this.length = 0.05;
}
public FreeformFinSet(Coordinate[] finpoints) throws IllegalFinPointException {
setPoints(finpoints);
}
/*
public FreeformFinSet(FinSet finset) {
Coordinate[] finpoints = finset.getFinPoints();
this.copyFrom(finset);
points.clear();
for (Coordinate c: finpoints) {
points.add(c);
}
this.length = points.get(points.size()-1).x - points.get(0).x;
}
*/
/**
* Convert an existing fin set into a freeform fin set. The specified
* fin set is taken out of the rocket tree (if any) and the new component
* inserted in its stead.
* <p>
* The specified fin set should not be used after the call!
*
* @param finset the fin set to convert.
* @return the new freeform fin set.
*/
public static FreeformFinSet convertFinSet(FinSet finset) {
log.info("Converting " + finset.getComponentName() + " into freeform fin set");
final RocketComponent root = finset.getRoot();
FreeformFinSet freeform;
List<RocketComponent> toInvalidate = Collections.emptyList();
try {
if (root instanceof Rocket) {
((Rocket) root).freeze();
}
// Get fin set position and remove fin set
final RocketComponent parent = finset.getParent();
final int position;
if (parent != null) {
position = parent.getChildPosition(finset);
parent.removeChild(position);
} else {
position = -1;
}
// Create the freeform fin set
Coordinate[] finpoints = finset.getFinPoints();
try {
freeform = new FreeformFinSet(finpoints);
} catch (IllegalFinPointException e) {
throw new BugException("Illegal fin points when converting existing fin to " +
"freeform fin, fin=" + finset + " points=" + Arrays.toString(finpoints),
e);
}
// Copy component attributes
toInvalidate = freeform.copyFrom(finset);
// Set name
final String componentTypeName = finset.getComponentName();
final String name = freeform.getName();
if (name.startsWith(componentTypeName)) {
freeform.setName(freeform.getComponentName() +
name.substring(componentTypeName.length()));
}
freeform.setAppearance(finset.getAppearance());
// Add freeform fin set to parent
if (parent != null) {
parent.addChild(freeform, position);
}
} finally {
if (root instanceof Rocket) {
((Rocket) root).thaw();
}
// Invalidate components after events have been fired
for (RocketComponent c : toInvalidate) {
c.invalidate();
}
}
return freeform;
}
/**
* Add a fin point between indices <code>index-1</code> and <code>index</code>.
* The point is placed at the midpoint of the current segment.
*
* @param index the fin point before which to add the new point.
*/
public void addPoint(int index) {
double x0, y0, x1, y1;
x0 = points.get(index - 1).x;
y0 = points.get(index - 1).y;
x1 = points.get(index).x;
y1 = points.get(index).y;
points.add(index, new Coordinate((x0 + x1) / 2, (y0 + y1) / 2));
// adding a point within the segment affects neither mass nor aerodynamics
fireComponentChangeEvent(ComponentChangeEvent.NONFUNCTIONAL_CHANGE);
}
/**
* Remove the fin point with the given index. The first and last fin points
* cannot be removed, and will cause an <code>IllegalFinPointException</code>
* if attempted.
*
* @param index the fin point index to remove
* @throws IllegalFinPointException if removing would result in invalid fin planform
*/
public void removePoint(int index) throws IllegalFinPointException {
if (index == 0 || index == points.size() - 1) {
throw new IllegalFinPointException("cannot remove first or last point");
}
ArrayList<Coordinate> copy = this.points.clone();
copy.remove(index);
validate(copy);
this.points = copy;
fireComponentChangeEvent(ComponentChangeEvent.BOTH_CHANGE);
}
public int getPointCount() {
return points.size();
}
public void setPoints(Coordinate[] points) throws IllegalFinPointException {
setPoints(Arrays.asList(points));
}
public void setPoints(List<Coordinate> points) throws IllegalFinPointException {
ArrayList<Coordinate> list = new ArrayList<Coordinate>(points);
validate(list);
this.points = list;
this.length = points.get(points.size() - 1).x;
fireComponentChangeEvent(ComponentChangeEvent.BOTH_CHANGE);
}
/**
* Set the point at position <code>i</code> to coordinates (x,y).
* <p>
* Note that this method enforces basic fin shape restrictions (non-negative y,
* first and last point locations) silently, but throws an
* <code>IllegalFinPointException</code> if the point causes fin segments to
* intersect.
* <p>
* Moving of the first point in the X-axis is allowed, but this actually moves
* all of the other points the corresponding distance back.
*
* @param index the point index to modify.
* @param x the x-coordinate.
* @param y the y-coordinate.
* @throws IllegalFinPointException if the specified fin point would cause intersecting
* segments
*/
public void setPoint(int index, double x, double y) throws IllegalFinPointException {
if (y < 0)
y = 0;
double x0, y0, x1, y1;
if (index == 0) {
// Restrict point
x = Math.min(x, points.get(points.size() - 1).x);
y = 0;
x0 = Double.NaN;
y0 = Double.NaN;
x1 = points.get(1).x;
y1 = points.get(1).y;
} else if (index == points.size() - 1) {
// Restrict point
x = Math.max(x, 0);
y = 0;
x0 = points.get(index - 1).x;
y0 = points.get(index - 1).y;
x1 = Double.NaN;
y1 = Double.NaN;
} else {
x0 = points.get(index - 1).x;
y0 = points.get(index - 1).y;
x1 = points.get(index + 1).x;
y1 = points.get(index + 1).y;
}
// Check for intersecting
double px0, py0, px1, py1;
px0 = 0;
py0 = 0;
for (int i = 1; i < points.size(); i++) {
px1 = points.get(i).x;
py1 = points.get(i).y;
if (i != index - 1 && i != index && i != index + 1) {
if (intersects(x0, y0, x, y, px0, py0, px1, py1)) {
throw new IllegalFinPointException("segments intersect");
}
}
if (i != index && i != index + 1 && i != index + 2) {
if (intersects(x, y, x1, y1, px0, py0, px1, py1)) {
throw new IllegalFinPointException("segments intersect");
}
}
px0 = px1;
py0 = py1;
}
if (index == 0) {
//System.out.println("Set point zero to x:" + x);
for (int i = 1; i < points.size(); i++) {
Coordinate c = points.get(i);
points.set(i, c.setX(c.x - x));
}
} else {
points.set(index, new Coordinate(x, y));
}
if (index == 0 || index == points.size() - 1) {
this.length = points.get(points.size() - 1).x;
}
fireComponentChangeEvent(ComponentChangeEvent.BOTH_CHANGE);
}
private boolean intersects(double ax0, double ay0, double ax1, double ay1,
double bx0, double by0, double bx1, double by1) {
double d = ((by1 - by0) * (ax1 - ax0) - (bx1 - bx0) * (ay1 - ay0));
double ua = ((bx1 - bx0) * (ay0 - by0) - (by1 - by0) * (ax0 - bx0)) / d;
double ub = ((ax1 - ax0) * (ay0 - by0) - (ay1 - ay0) * (ax0 - bx0)) / d;
return (ua >= 0) && (ua <= 1) && (ub >= 0) && (ub <= 1);
}
@Override
public Coordinate[] getFinPoints() {
return points.toArray(new Coordinate[0]);
}
@Override
public double getSpan() {
double max = 0;
for (Coordinate c : points) {
if (c.y > max)
max = c.y;
}
return max;
}
@Override
public String getComponentName() {
//// Freeform fin set
return trans.get("FreeformFinSet.FreeformFinSet");
}
@Override
protected RocketComponent copyWithOriginalID() {
RocketComponent c = super.copyWithOriginalID();
((FreeformFinSet) c).points = this.points.clone();
return c;
}
private void validate(ArrayList<Coordinate> pts) throws IllegalFinPointException {
final int n = pts.size();
if (pts.get(0).x != 0 || pts.get(0).y != 0 ||
pts.get(n - 1).x < 0 || pts.get(n - 1).y != 0) {
throw new IllegalFinPointException("Start or end point illegal.");
}
for (int i = 0; i < n - 1; i++) {
for (int j = i + 2; j < n - 1; j++) {
if (intersects(pts.get(i).x, pts.get(i).y, pts.get(i + 1).x, pts.get(i + 1).y,
pts.get(j).x, pts.get(j).y, pts.get(j + 1).x, pts.get(j + 1).y)) {
throw new IllegalFinPointException("segments intersect");
}
}
if (pts.get(i).z != 0) {
throw new IllegalFinPointException("z-coordinate not zero");
}
}
}
}