Map Mode, Map Parameter unexpected behavior

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drmacro
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Map Mode, Map Parameter unexpected behavior

Post by drmacro »

Not sure I understand why this happens. Adjusting Map Parameter in in the following video. At 0.0 it is as expected, at 0.25 as expected. At 0.5 it changes the side of the path it is following. I'm guessing it has to do with the normal vector changing along the curve? But, is this the correct behaviour? If yes is there a way it can be made to follow the path at the defined offset?
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Vincent B
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Re: Map Mode, Map Parameter unexpected behavior

Post by Vincent B »

the mapping is flipping along the curvature.
here 0,7.
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Vincent B
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Re: Map Mode, Map Parameter unexpected behavior

Post by Vincent B »

To follow the surface, mapping could be like this, but Z offset should be different. :D
I used a datumpoint because it has not orientation.
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drmacro
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Re: Map Mode, Map Parameter unexpected behavior

Post by drmacro »

Vincent B wrote: Sat Feb 04, 2023 7:48 pm To follow the surface, mapping could be like this, but Z offset should be different. :D
I used a datumpoint because it has not orientation.
If I understand what you propose, it does not do what I intended. (I apologize, I didn't state the intention.)

The intent is to have the cylindrical Extrude001 to follow the normal of the curve, but in the center of the surface of Extrude.
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edwilliams16
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Re: Map Mode, Map Parameter unexpected behavior

Post by edwilliams16 »

Could make the cylinder extrusion symmetric and cut away any excess that pokes out the bottom.

I don't see any Frenet modes otherwise working because the normal flips.
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drmacro
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Re: Map Mode, Map Parameter unexpected behavior

Post by drmacro »

edwilliams16 wrote: Sat Feb 04, 2023 11:59 pm Could make the cylinder extrusion symmetric and cut away any excess that pokes out the bottom.

I don't see any Frenet modes otherwise working because the normal flips.
Thanks for the idea.

Using the Frenet mode was just first WAG. I wanted to make a parametric example of using Map Mode to change the location of the cylinder sketch so it would move normal to the surface.

Probably needs some more thought. :lol:
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Re: Map Mode, Map Parameter unexpected behavior

Post by edwilliams16 »

@drmacro
Normal to edge works - it only references the tangent direction.
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drmacro
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Re: Map Mode, Map Parameter unexpected behavior

Post by drmacro »

edwilliams16 wrote: Sun Feb 05, 2023 1:10 am @drmacro
Normal to edge works - it only references the tangent direction.
That does indeed work. I had done that initially, but, tried the Frenet, saw the issue, and wanted to see if it was expected behaviour...so I could adjust my expectations. ;)
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