class Funnel : Model {

    var stemSize = Vector2(30, 6)
    var coneSize = Vector2(50, 30)
    var thickness = 1.2

    var tipAngle = 45


    fun funnel( large : Shape2d ) : Shape3d {
        val midD = stemSize.y * 1.5
        val mid = Circle( midD / 2 )
        val small = Circle( stemSize.y / 2 )

        val funnel = ExtrusionBuilder().apply {
            crossSection( large.offset( thickness ) )
            forward( thickness )
            crossSection()
            crossSection( large )
            forward( coneSize.y -thickness)
            crossSection( mid )
            forward( stemSize.x )
            crossSection( small )
            forward( stemSize.y )

            crossSection()
            crossSection( - thickness )
            forward( - stemSize.y )
            crossSection()
        
            forward( - stemSize.x - thickness/2 )
            crossSection ( mid.offset( - thickness ) )
            forward( - coneSize.y + thickness / 2)
            crossSection( large.offset( - thickness ) )
        
        }.buildClosed()

        val sliceTip = Cube( coneSize.x ).centerXY()
            .rotateX( tipAngle )
            .translateZ( stemSize.x + coneSize.y )

        return funnel - sliceTip
    }

    //@Piece
    //fun squashed() = funnel( Circle( coneSize.x / 2 ).scaleX( 0.5 ) ) //intersection Cube(1000).centerXY().topTo(20)

    @Piece
    fun heart() : Shape3d {
        val half = Circle( 5.5 ).translate( 4, 3 ) hull Circle( 1 ).translate(0, -8)
        val heart = half.mirrorX().also().scale( coneSize.x / 20 )
        return funnel( heart ) intersection Cube(1000).centerXY().topTo(27)
    }
    
    override fun build() : Shape3d {
        return funnel( Circle( coneSize.x / 2 ) )
    }
}