给线k动画的思路。 这个对我没用不过，很重要

 sp = splineShape()

addnewSpline sp

addKnot sp 1 #corner #line [0,0,0]

addKnot sp 1 #corner #line [0,0,0]

updateShape sp
 
 ---先生成原点的 点点 在给点轨迹
 /*
 
dis= getKnotPoint  sp 1 2
 
 dis_one= getKnotPoint  sp 1 1
dist = distance  dis_one dis
*/
 animateVertex sp 1
 animateVertex sp 2
 
 animate on
(

 --setKnotSelection sp 1 #(2)

at time 0  setKnotPoint  sp 1 2 [0,0,0]

at time 20  setKnotPoint  sp 1 2 [10,50,0]

)

 animateVertex $ 1
 animateVertex $ 2

animateVertex $ #all ---用这个
 animate on
(
 --setKnotSelection sp 1 #(2)

at time 0   $.Spline_1___Vertex_1 =  [30,-13.0265,0]

at time 20  $.Spline_1___Vertex_2  =[50,-13.0265,0]

)
getKnotPoint  sp 1 2
 at time
updateShape $

$.Spline_1___InVec_1 [0,0,0] value: [-75,33,0] -- animatable

$.Spline_1___Vertex_1 Point3 value: [-75,33,0] -- animatable

$.Spline_1___OutVec_1 Point3 value: [-50,0,0] -- animatable

$.Spline_1___InVec_2 Point3 value: [-20,-33,0] -- animatable

$.Spline_1___Vertex_2 Point3 value: [7,-66,0] -- animatable

$.Spline_1___OutVec_2 Point3 value: [32,-95,0] -- animatable

$.Spline_1___Vertex_1=

/*

 fg =

addKnot sp 1 #corner #line [-20,-11,0]

addKnot sp 1 #corner #line [20,-10,0]

--close sp 1

addKnot sp 1 #corner #line [20,-20,0]
select sp

pivot

pp =getKnotPoint  sp 1 2
addModifier 
 */
 --通过上面的探索 知道了线的动画的k发
 --1. 创建点
 --2. 给点赋予控制器
 --3.给点动画  （函数的应用在max8 之上）
 
 
 sp = splineShape()

addnewSpline sp

addKnot sp 1 #corner #line [0,0,0]

addKnot sp 1 #corner #line [10,10,0]

updateShape sp
 
---2
 animateVertex sp 1
 animateVertex sp 2

---3
select sp
 animate on
(
 --setKnotSelection sp 1 #(2)

at time 0   $.Spline_1___Vertex_1 =  [30,-13.0265,0]

at time 20  $.Spline_1___Vertex_1  =[50,-13.0265,0]

)