Как создать конусные заклинания?

function Is2cc takes real r, real cx, real cy, real px1, real py1, real px2, real py2 returns boolean
        local real dx = 0.00 
        local real dy =  0.00 
        local real a =  0.00 
        local real b = 0.00  
        local real c = 0.00 
        
        set px1 = px1 - cx
        set py1 = py1 - cy
        set px2 = px2 - cx
        set py2 = py2 - cy
        set dx = px2 - px1
        set dy = py2 - py1
        set a = dx * dx + dy * dy
        set b = 2.00 * ( px1 * dx + py1 * dy )
        set c = px1 * px1 + py1 * py1 - r * r
        
        if ( -b < 0.00 ) then
            return ( c < 0.00 )
        elseif ( -b < ( 2.00 * a ) ) then
            return ( ( 4.0 * a * c - b * b ) < 0 )
        endif
        return ( a + b + c < 0 )
    endfunction