//Visit fields of large images on small screens.
//N. Vischer 04.10.13 15:26
//Defines a matrix of fields (rows * columns) which then can be visited
//sequentially at desired magnification (zoom in %) by a single keystroke [shortcut F].
//After last field, program returns to normal view, showing the entire image.
//-> Watch blue overview rectangle (top left) to see which field is active
//-> or choose "Circles for Orientation[o]" to show ovals for 500 ms.

var columns=1, rows=2, zoom = 70;//define behaviour here

var field = 0;

macro "Visit next Field [f]"{
	if (field >= columns * rows){
		run("Original Scale");
		field = 0;
		setLocation(0, 90);
		return;
	}
	setLocation(0, 0);
	col = field%columns;
	row = floor(field/columns);
	fieldWidth = getWidth/columns;
	fieldHeight = getHeight/rows;
	
	x = (col  + 0.5)* fieldWidth;
	y = (row  + 0.5)* fieldHeight;
	run("Set... ", "zoom=&zoom x=&x y=&y");
	field++;
}


macro "Circles for Orientation [o]"{
	makeOval(0, 0, getWidth, getHeight);
	setKeyDown("alt");
	makeOval(getWidth *0.25,  getHeight * 0.25, getWidth *0.5,  getHeight * 0.5);
	wait(500);
	run("Select None");
}