How to project point on surface with function project_pt_onto_surf

[CNCLaundry]

Trying to project a point on a trimmed revolved surface, the function project_pt_onto_surf returnes mostly FALSE .

I think it depends on the guess starting parameters uv_in .

How to find good starting values?

 

Thanks in advance.

 

PS: Tested under Mastercam X2MR2

 

[ 04-23-2009, 11:22 AM: Message edited by: Norbert Dalhoff ]

[Pete Rimkus from CNC Software Inc.]

Norbert,

One way to do it is to use several different start guesses. Since you've got the trimmed surface entity, you have it's UV extents. Use several different start UVs within these extents and you'll probably have some success.

[CNCLaundry]

Pete,

thanks for your suggestion. It works fine if i take the mid of the uv extents of the surface. My fault was that i always took 0.5 for U and V. I thougt U and V run from 0.0 to 1.0. But that isn't guaranteed.

[Pete Rimkus from CNC Software Inc.]

"...I thought U and V run from 0.0 to 1.0. But that isn't guaranteed..."

 

That is true...you need to look at the min and max UVs of the surface (as you discovered).

 

Glad to hear it's working for you now.