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ZeroLengthCurve  
#1 Posted : Wednesday, September 21, 2022 11:10:49 PM(UTC)
ZeroLengthCurve

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Joined: 5/15/2008(UTC)
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Hi.

I have been having an exceedingly frustrating time trying to take a 5 point spline set up as a hull station at a given frame and "Coincident" constraining it to a position on a curve (control point spline) that represents the Top Deck. I had a working pair of a line and a spline. Then, when I moved the spline independently of the first curve, then later moved the first curve (the line), the relationship went bonkers. Forcing resolve links didn't help. Restarting the app didn't help. I may havd done too many undos and hit save. I wish there were a way to deep select the undo stack and only undo an operation that is independent of/not likely to cause downstream negative changes.


Longer, my intent:

I want to attach the stations (spline's) highest point (say #1) to a reference curve whether its oeiented y-y or x-x, then to an arbitrary XYZ position along a curve (the Top Deck), so snap the Y and Z for the station to the Top Deck.

I want to attach the station's lowest endpoint (say, #5) to the keel's Y=0 point of the station spline. Much of the keel is Z=0, but it can rise from the cut-up til it reaches the transom, say, up to 6 meters.

Ultimately, I want to be able to constrain the station angle to a certain angle inward, from top down, from #1 to #3. Then, I want to be able to as necessary slide the Top-Deck-locates constraint guide forward and aft as coincident to that Top Deck edge. Once happy, set and lock, then repeat the same for the remaining stations.

As I do ao, I want the centerline constraint to if coincident at z=0, be at 0. If I slide the station far enough aft to the keel cutup and the cutup leaves Z=0 and now is Z=1.15, the point should remain as Y=0, but follow the x and z for its loval point as/while the upper point may see its Y vary according to the shape of the Top Deck. So, the length of the curve between points 3, 4, and 5 can increas from forward to rhe maximum beam, then decrease the farther aft it goes.

There may be as many as 20 or 40 stations, each with own constraint. Most will follow the pattern above, but the bow area will see points 1, 2, and 3 have more length of curve.

"Curves not planar" seems like an unnecessary limitation. It seems that the finalization of the constraint for a pair if curves would just snap the dependent curve to its new position and not theow fits about planarity. After all, when the constraint DID work, I could drag the parent/first/ref curve all over the file and I was happy.

Now, I'm frustrated I cannot reproduce it, and saving along rhe way seems to have wiped out the undo stack and I cannot get back to a working example of what I was happy with.


Thanks for any input/feedback.


....



Adding forgotten ideas hear to leave the original flow intact:

Optionally, I want to make the radius remain fixed/constrained within a slack or upoer/lower limit so the hu doesn't take on wacky shaping or non fair or non-parallel stations. This may or may not be compatible.

But, my mind burns and melts trying to figure out a rational, repeatable, reliable, sharable workflow. I go down rabbit holes and only come out frustrated and wanting to just give up. I'm feelnthat a grid or tabular dialog may be ultimately better.

Edited by user Wednesday, September 21, 2022 11:26:45 PM(UTC)  | Reason: I added below the dots some stuff I forgot to include.

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