用maya制造环形跑道模型和材质（英文）

(5) Scale the curve, up or down, until the arc length value is about 3840 then snap the end point to the start point of the curve. The total circuit length will then be approximately 3.84Km. Notice how this value is a multiple of 2 – you will see why I have chosen this later.

　　

　　(6) Add height to the track by moving the CVs in the Y axis – made easier by selecting in the top view and moving in a side or front view. Notice in the track design, a 30 metre maximum height difference of the two small downhill sections, and the longer sweeping uphill.

　　

(7) Offset Curve 3 times either side of the centreline. The track width will be 13m so offsetting four lines +6, -6, +6.5, -6.5, will compensate for the edge of the tarmac and the white line. Then offset twice again +9.5, -9.5 that will act as the outer edge of the grass verge.

　　

　　(8) Again using the Arc Length Tool mark out the centreline approx. every 128m. Notice how I chose 3.84km as the track length. This will ensure that the circuit has 30 sections of 128m. This simplifies the modelling for purposes of this tutorial.