FeatureScript Parametric Surface and Curve: Can't change equation Z = f(x,y), X,Y,Z = f(t)

7wealacmcgfshp28dasnbrru_8fmdcurynplbkluxfzf9klcb

I've been playing with Parametric Surface and Parametric Curve.

I am unable to change the equation Z = f(#x, #y) or X = f(#t), etc.

I can change min,max x,y or t
I can change number of curves/points
I can hide/show curves
I can visualize before and after using the slider
... but when I change the equation the surface/curve remains unaltered.

This happens in copies of FeatureScript examples as well as original documents.

Any ideas what I'm missing?

mahir

Hi 7weal..... I wrote those featurescripts, and I agree they can be a bit particular regarding equation input. Unfortunately, that is a byproduct of using a FS workaround to allow native parsing of built-in functions like sin/cos.

That said, if you follow these specific rules (mentioned in the FS info doc), you should be ok.

1. Create a Define Parameter feature that names the free variable ("t" by default).
2. Create a Variable with the same name (in this case "t"). I usually set it equal to 1.
3. Create the Parametric curve feature, making sure each XYZ equation evaluates to a length. For example, assuming 0<t<1, the equations below will create a helix with 10 rotations and diameter/length equal 20mm.
      X = 10*cos(#t*10*360*deg)*mm
      Y = 10*sin(#t*10*360*deg)*mm
      Z = 20*#t*mm
   As you're writing the equations, after you move to a different input field, the equation field should change to evaluate to a length.
4. After clicking ok in the FS dialog, suppress the #t variable (but not the Define Parameter).
5. Your curve should generate.

Very important: anytime you want to edit the equations, you will need to unsuppress the variable(s). After editing, you must then resuppress for the curve/surface to generate.