var view_transform =
    [[1, 0, 0],
     [0, 1, 0],
     [0, 0, 1]];
    







            

var key_state = {};
var key_state_augmentation_timeout = 150; // the permissible time in milliseconds since the last key event to still allow the key state to augment instead of clearing.

function addKeyListener(keycode, func){

					if(selected_points[i] == highlight_object){
					   selected_points.splice(i, 1); // deselect point
					   alreadySelected = true; 
					   break; }}}
			else{
				selected_points.length = 0;}
				
			if(!alreadySelected) selected_points.push(highlight_object); }
			if(!alreadySelected && highlight_object < points.length) selected_points.push(highlight_object); }

		else if(!key_state[16] || !key_state[16].state)
			selected_points.length = 0; }
		
		
	else if(lasts && mouse_dragging ){  // drag actions
		

//
// equation at:
// http://inside.mines.edu/~gmurray/ArbitraryAxisRotation/ArbitraryAxisRotation.html
// creates a rotation matrix about the given vector.
//
function vector_rotation(vector, s){
	if(!vector) throw "vector argument to vector_rotation missing";
	if(!s) throw "angle argument to vector_rotation missing";
	if(s === null || s === undefined) throw "angle argument to vector_rotation missing";
	
    var len = Math.sqrt(vector[0]*vector[0]
                        + vector[1]*vector[1]
                        + vector[2]*vector[2]);

    var u = vector[0]/len;
    var v = vector[1]/len;