ImageJ1 macros that create X/Y mirrors of the active ROI

Mirror_Selection.ijm

// ImageJ1 macros that create X/Y mirrors of the active ROI
// http://thread.gmane.org/gmane.comp.java.imagej/35570

macro "Contralateral in X [F1]" {
	mirrorROI(-1, 1);
}
macro "Contralateral in Y [F2]" {
	mirrorROI(1, -1);
}

function mirrorROI(fx, fy) {
	roi = selectionType();
	if (roi>8 || roi<0)
		exit("Cannot mirror current selection");
	getSelectionBounds(upperLeftX, upperLeftY, null, null);
	getSelectionCoordinates(x, y);
	aX = newArray(x.length);
	aY = newArray(x.length);
	for (i=0; i<x.length; i++) {
		aX[i] = fx * x[i];
		aY[i] = fy * y[i];
	}
	makeSelection(roi, aX, aY);
	setSelectionLocation(upperLeftX, upperLeftY);
}