Examples with LineSegment3 com.ardor3d.math.LineSegment3 used on opensource projects

Example 1 with LineSegment3

use of com.ardor3d.math.LineSegment3 in project energy3d by concord-consortium.

the class MeshLib method computeOutline.

public static ArrayList<ReadOnlyVector3> computeOutline(final FloatBuffer buf) {
    final Map<LineSegment3, Boolean> visitMap = new HashMap<LineSegment3, Boolean>();
    for (int i = 0; i < buf.limit(); i += 9) {
        for (int trianglePointIndex = 0; trianglePointIndex < 9; trianglePointIndex += 3) {
            buf.position(i + trianglePointIndex);
            Vector3 p1 = new Vector3(buf.get(), buf.get(), buf.get());
            buf.position(i + (trianglePointIndex + 3) % 9);
            Vector3 p2 = new Vector3(buf.get(), buf.get(), buf.get());
            if (p2.getX() < p1.getX() || (p2.getX() == p1.getX() && p2.getY() < p1.getY())) {
                final Vector3 tmp = p1;
                p1 = p2;
                p2 = tmp;
            }
            final LineSegment3 line = new LineSegment3(p1, p2);
            final Boolean pastVisit = visitMap.get(line);
            if (pastVisit == null) {
                visitMap.put(line, true);
            } else {
                visitMap.put(line, false);
            }
        }
    }
    final ArrayList<ReadOnlyVector3> outlinePoints = new ArrayList<ReadOnlyVector3>();
    for (final LineSegment3 line : visitMap.keySet()) {
        if (visitMap.get(line)) {
            final Vector3 negativeEnd = line.getNegativeEnd(null);
            outlinePoints.add(negativeEnd);
            outlinePoints.add(line.getPositiveEnd(null));
        }
    }
    final ArrayList<ReadOnlyVector3> sortedOutlinePoints = new ArrayList<ReadOnlyVector3>(outlinePoints.size() / 2);
    sortedOutlinePoints.add(outlinePoints.get(0));
    ReadOnlyVector3 lastPoint = outlinePoints.get(1);
    sortedOutlinePoints.add(lastPoint);
    outlinePoints.remove(1);
    outlinePoints.remove(0);
    while (!outlinePoints.isEmpty()) {
        boolean foundSomething = false;
        for (int i = 0; i < outlinePoints.size(); i++) {
            if (Util.isEqual(outlinePoints.get(i), lastPoint)) {
                final int otherEndIndex = i % 2 == 0 ? i + 1 : i - 1;
                lastPoint = outlinePoints.get(otherEndIndex);
                sortedOutlinePoints.add(lastPoint);
                outlinePoints.remove(Math.max(i, otherEndIndex));
                outlinePoints.remove(Math.min(i, otherEndIndex));
                foundSomething = true;
                break;
            }
        }
        if (!foundSomething) {
            break;
        }
    }
    // remove last point if duplicated of first point
    if (Util.isEqual(sortedOutlinePoints.get(0), sortedOutlinePoints.get(sortedOutlinePoints.size() - 1))) {
        sortedOutlinePoints.remove(sortedOutlinePoints.size() - 1);
    }
    return sortedOutlinePoints;
}