spawn_point = function()
	return {
		x = math.random(Viewport.x, Viewport.x+Viewport.w),
		y = math.random(Viewport.y, Viewport.y+Viewport.h),
	}
end

round = function(f)
	-- apparently this is wrong for one floating point under 0.5
	-- there's an alleged better way at https://stackoverflow.com/questions/18313171/lua-rounding-numbers-and-then-truncate/58411671#58411671
	return math.floor(f+0.5)
end