Method parsePath

ij/src/main/java/ij/gui/ShapeRoi.java:793–929

Parses the geometry of this ROI's shape by means of the shape's PathIterator; Depending on the task and rois argument it will: - create a single non-Shape Roi and add it to rois in case there is only one subpath, otherwise add this Roi unchanged to <c

(PathIterator pIter, int task, ArrayList rois)

	 * (see @link #shapeToRois()} for details;
	 * @return Total length if task = GET_LENGTH.*/
	double parsePath(PathIterator pIter, int task, ArrayList rois) {
		if (pIter==null || pIter.isDone())
			return 0.0;
		double pw = 1.0, ph = 1.0;
		if (imp!=null) {
			Calibration cal = imp.getCalibration();
			pw = cal.pixelWidth;
			ph = cal.pixelHeight;
		}
		float xbase = (float)getXBase();
		float ybase = (float)getYBase();

		FloatArray xPoints = new FloatArray();    //vertex coordinates of current subpath
		FloatArray yPoints = new FloatArray();
		FloatArray shapeArray = new FloatArray(); //values for creating a GeneralPath for the current subpath
		boolean getLength = task == GET_LENGTH;
		int nSubPaths = 0;           // the number of subpaths
		boolean horVertOnly = true; // subpath has only horizontal or vertical lines
		boolean closed = false;
		//boolean success = false;
		float[]  fcoords = new float[6];  // unscaled float coordinates of the path segment
		double[] coords  = new double[6]; // scaled (calibrated) coordinates of the path segment
		double startCalX = 0.0;   // start x of subpath (scaled)
		double startCalY = 0.0;   // start y of subpath (scaled)
		double lastCalX = 0.0;    // x of previous point in the subpath (scaled)
		double lastCalY = 0.0;    // y of previous point in the subpath (scaled)
		double pathLength = 0.0;  // calibrated pathLength/perimeter of current curve
		double totalLength = 0.0; // sum of all calibrated path lengths/perimeters
		double uncalLength = 0.0; // uncalibrated length of polygon, NaN in case of curves
		boolean done = false;
		while (true) {
			int segType = done ? NO_SEGMENT_ANY_MORE : pIter.currentSegment(fcoords);  //read segment (if there is one more)
			int nCoords = 0;               //will be number of coordinates supplied with the segment
			if (!done) {
				nCoords = nCoords(segType);
				if (getLength) {           //make scaled coodinates to calculate the length
					pIter.currentSegment(coords);
					scaleCoords(coords, nCoords, pw, ph);
				}
				pIter.next();
				done = pIter.isDone();
			}

			//IJ.log("segType="+segType+" nCoord="+nCoords+" done="+done+" nPoi="+nPoints+" len="+pathLength);
			if (segType == NO_SEGMENT_ANY_MORE || (segType == PathIterator.SEG_MOVETO && xPoints.size()>0)) {
				// subpath finished: analyze it & create roi if appropriate
				closed = closed || (xPoints.size()>0 && xPoints.get(0) == xPoints.getLast() && yPoints.get(0) == yPoints.getLast());
				float[] xpf = xPoints.toArray();
				float[] ypf = yPoints.toArray();
				if (Double.isNaN(uncalLength) || !allInteger(xpf) || !allInteger(ypf))
					horVertOnly = false;         //allow conversion to rectangle or traced roi only for integer coordinates
				boolean forceTrace = getLength && (!done || nSubPaths>0);  //when calculating the length for >1 subpath, assume traced rois if it can be such
				int roiType = guessType(xPoints.size(), uncalLength, horVertOnly, forceTrace, closed);
				Roi roi = null;
				if (roiType == COMPOSITE && rois != null) { //for ShapeRois with curves, we have the length from the path already, make roi only if needed
					Shape shape = makeShapeFromArray(shapeArray.toArray());  //the curved subpath (image pixel coordinates)
					FloatPolygon fp = getFloatPolygon(shape, FLATNESS, /*separateSubpaths=*/ false, /*addPointForClose=*/ false, /*absoluteCoord=*/ false);
					roi = new PolygonRoi(fp, FREEROI);