topic Re: How can I use the 'SHAPE_CLASS_ID' ? in 3ds Max Programming Forum

How can I use the 'SHAPE_CLASS_ID' ?

Anonymous — Fri, 16 Aug 2019 02:18:51 GMT

I develop file converter using 3DS MAX SDK.
I want to use the line from 'SHAPE_CLASS_ID' from INode.
and I get the ShapeObject like the source code show below.

////////////////////////////////////////////////////////////////////////////////
ObjectState os = pNode->EvalWorldState(0);
ShapeObject* shape = (ShapeObject*)os.obj;
PolyShape pShape;
shape->MakePolyShape(0, pShape);
////////////////////////////////////////////////////////////////////////////////

but I can't find the way to get normal vertex of the shape.
Is there any way to get the normal vertex of line vertex?

Pleace let me know the way to get normal vector, if you know.

Re: How can I use the 'SHAPE_CLASS_ID' ?

denisT.MaxDoctor — Fri, 16 Aug 2019 18:39:30 GMT

There is no such thing as "normal" for spline. There is a tangent. It's objective. But "normal" is a subjective thing - any vector that is perpendicular to the tangent.

Re: How can I use the 'SHAPE_CLASS_ID' ?

Anonymous — Tue, 20 Aug 2019 14:30:24 GMT

Oh, Thanks.
I get the Tangent Vector using 'TangentPiece3D' function.
It seems that perpendicular vector of 'Tangent Vector' is 'Normal Vector' as I understand.

But I can't know how to get perpendicular vector of 'Tangent Vector'.
Is there any Information or sample about it?
Please let me know.

Re: How can I use the 'SHAPE_CLASS_ID' ?

istan — Tue, 20 Aug 2019 16:05:56 GMT

I am not sure, you know what you ask for, but a normal to a vector Point3(x, y, z) is for instance (since Infinite): Point3(-y, x, 0)..