Discrepancy in offset commands between Rhino native and Grasshopper

unhandled

#1

2018-04-02_10-50-56
I found that offset curves created by Rhino native command offset and Grasshopper Offset component are different. The offset component and python command Rhino.Geometry.Curve.Offset give roughly same curve.
The options that I feed to Rhino native offset is CornerType=Sharp, Tolerance=0.001, and basically I’m feeding the same options to python RHino.Geometry.Curve.Offset.
It seems like the curve produced by Rhino native command is much more precise.
Is there a way to get an offset of curves as precise as Rhino native command in Grasshopper environment?

Thanks.


(Laurent Delrieu) #2

First, it is surely better to post the curve and grasshopper script.
2nd, Grasshopper need a plane as Rhino. By default for me it is Cplane in Rhino, Grasshopper take XY plane by default.
In 3d you have an infinity of offset !!!


#3

Sooooorry, there is a Patch component which approximates the input surface and the patch surface that is being output from the Patch component were slightly different… That’s why two offset curves do not match.


(Laurent Delrieu) #4

No problem, there are some bugs in Rhino offset for polyline. But bugs are shared on Grasshopper and Rhino as they rely on Rhinocommon.
See this in 2D