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XirusCurveFromSurfacePoints Tangency constraints

Just tried the new XirusCurveFromSurfacePoints command and I like this tool, and I have some suggestions to make it even better.

During creation.
-have a curvature graph displayed for the curve so you can judge the shape before you commit. Like Rhino Blend Crv.
-have the ability to adjust tangent strength during creation. Like Rhino BlendCrv.

After creation.
-Symmetrical adjustment of tangent strength to adjust shape, with curvature graph.
-Constrained tangency adjustment.

Right now if you grab the Xirus curve point you can freely move it which breaks symmetry of the curve and tangency with the Xirus surface it is attached to. One of the ways I imagine how this could work is to be able to align one of the Gumball Axis with the drag handle. This can be done currently with Relocate Gumball, but if you have to Relocate the Gumball everytime you want to adjust tangency strength, that would be a lot of unnecessary clicks. I’m recreating the y-branch and relocated the Gumball below.

Hi Mark,

Thank you for your detailed feedback. Your suggestions for adding and extending the GUI will be very helpful when updating this command.


Hi Pablo,

After using the software for a bit I believe it would be extremely helpful to be able to constrain movements for the augmented quantities. Right now it is very easy to have unwanted movements.

While this may not matter if you are doing purely organic shape modeling, it matters a lot to me. All my modeling is hard-surface modeling and as such I need precise controls.

I believe this has been mentioned before maybe, but I also believe that the Gumball should either default to be constrained to the tangent plane and it’s orientation when you select an augmented surface point. For example the Gumball X and Y axis should align themselves with the U and V tangency handles and the Z axis should align itself with the curvature handle.

This would automatically constrain the movement of the Gumball handles. Even if the default behavior is to have the Gumball aligned to World or CPlane, this would be a very useful option in my opinion.

Thanks for pointing out the gumball alignment, we’ll definitely look into it.
First provided way of constraining tangency will be through a dialog or graph after creation, via a slider + numerical input specifying relative scaling, in an update soon. This is in the wish-list since long time but could not be addressed till recently.