library PointInRect

    // Returns a boolean that tells whether the point is inside a rectangle.
    // (px , py) = Point to check
    // (cx , cy) = lower left corner of the rect
    // (ax , ay) = upper left corner
    // (bx , by) = lower right corner
    function IsPointInRect takes real px , real py , real cx , real cy , real ax , real ay , real bx , real by returns boolean        
        local real dot1 = (px-cx)*(ax-cx) + (py-cy)*(ay-cy)
        local real dot2 = (ax-cx)*(ax-cx) + (ay-cy)*(ay-cy)
        local real dot3 = (px-cx)*(bx-cx) + (py-cy)*(by-cy)
        local real dot4 = (bx-cx)*(bx-cx) + (by-cy)*(by-cy)
        
        return dot1 >= 0 and dot1 <= dot2 and dot3 >= 0 and dot3 <= dot4
    endfunction
    
endlibrary