CATIA Automation 编程绘制样条曲线

之前用 VC 编写了画圆的简单例子，今天试了一下绘制样条曲线的功能。

还是按照 Automation 的基本流程：

1 录制宏命令

Language="VBSCRIPT"

Sub CATMain()

Set partDocument1 = CATIA.ActiveDocument

Set part1 = partDocument1.Part

Set bodies1 = part1.Bodies

Set body1 = bodies1.Item("PartBody")

Set sketches1 = body1.Sketches

Set sketch1 = sketches1.Item("Sketch.1")

Set factory2D1 = sketch1.OpenEdition()

Set controlPoint2D1 = factory2D1.CreateControlPoint(120.000000, -30.000000)

controlPoint2D1.ReportName = 5

Set controlPoint2D2 = factory2D1.CreateControlPoint(140.000000, -20.000000)

controlPoint2D2.ReportName = 6

Set controlPoint2D3 = factory2D1.CreateControlPoint(170.000000, 30.000000)

controlPoint2D3.ReportName = 7

Set controlPoint2D4 = factory2D1.CreateControlPoint(190.000000, -20.000000)

controlPoint2D4.ReportName = 8

Set controlPoint2D5 = factory2D1.CreateControlPoint(140.000000, -70.000000)

controlPoint2D5.ReportName = 9

Set controlPoint2D6 = factory2D1.CreateControlPoint(120.000000, -30.000000)

controlPoint2D6.ReportName = 10

Dim arrayOfObject1(5)
Set arrayOfObject1(0) = controlPoint2D6
Set arrayOfObject1(1) = controlPoint2D5
Set arrayOfObject1(2) = controlPoint2D4
Set arrayOfObject1(3) = controlPoint2D3
Set arrayOfObject1(4) = controlPoint2D2
Set arrayOfObject1(5) = controlPoint2D1
Set spline2D1 = factory2D1.CreateSpline(arrayOfObject1)

spline2D1.ReportName = 11

Set constraints1 = sketch1.Constraints

Set reference1 = part1.CreateReferenceFromObject(controlPoint2D1)

Set reference2 = part1.CreateReferenceFromObject(controlPoint2D6)

Set constraint1 = constraints1.AddBiEltCst(catCstTypeOn, reference1, reference2)

constraint1.Mode = catCstModeDrivingDimension

sketch1.CloseEdition 

part1.InWorkObject = sketch1

part1.Update 

End Sub

2 翻译成 VC 代码

ControlPoint2DPtr cp[6];

cp[0] =  factory2D->CreateControlPoint(60.000000, -70.000000);
cp[1] =  factory2D->CreateControlPoint(-10.000000, -90.000000);
cp[2] =  factory2D->CreateControlPoint(-100.000000, -50.000000);
cp[3] =  factory2D->CreateControlPoint(30.000000, 70.000000);
cp[4] =  factory2D->CreateControlPoint(80.000000, 20.000000);
cp[5] =  factory2D->CreateControlPoint(60.000000, -70.000000);

SAFEARRAY * psa;
SAFEARRAYBOUND rgsabound[1];

rgsabound[0].lLbound = 0;
rgsabound[0].cElements = 1;
psa = SafeArrayCreate(VT_VARIANT, 1, rgsabound);

if(psa == NULL) return E_OUTOFMEMORY;

Spline2DPtr spline = factory2D->CreateSpline(psa);

SafeArrayDestroy(psa);

代码中没有把 ControlPoint2D 和 Spline2D 联系起来，因为尝试了多种方式都没起作用，就暂时去除了相关代码。

3 修正代码

本来根据宏代码，应该在CreateSpline时传递控制点信息，但是参数是 SAFEARRAY *，试了许久还是不知道如何传递才能起作用。

也罢，重新查看 Spline2D 的成员，发现了 InsertControlPointAfter 方法。

添加代码：

spline->InsertControlPointAfter(cp[0], 0);
spline->InsertControlPointAfter(cp[1], 1);
spline->InsertControlPointAfter(cp[2], 2);
spline->InsertControlPointAfter(cp[3], 3);
spline->InsertControlPointAfter(cp[4], 4);
spline->InsertControlPointAfter(cp[5], 5);

总体来说，用 VC 来实现 CATIA Automation 与 VB 比还是差很多，需要处理很多底层的内存操作和类型转换。