Tween Shape

[largento]

I was wondering if there was a plug-in that would create a halfway point spline ring between two spline rings.

 

In other words, if I were to have two spline rings that are too far apart. Is there a way that I could select both and then have a new spline ring that would appear halfway between them and also tween the shape (like Flash does)?

 

I tend to start on the low end as far as splines when I'm modeling and add more as I need to. I sometimes realize I need that extra spline ring, but manually adding CPs between them doesn't always give the result I want. Especially since I avoid using the bias handles.

[robcat2075]

I sometimes realize I need that extra spline ring, but manually adding CPs between them doesn't always give the result I want.

 

What is the unwanted result?

 

 

Lessee...

 

-You know that Holding the Shift key while stitching in a new spline will maintain the curvature of the splines that were there, I presume. That's usually been enough for me to add a spline where I need one.

 

-Splitpatch will do a 2x2 subdivision of all selected patches. You could use that and manually delete the undesired CPs and splines that are created beyond the inbetween spline you do want. ( Lasso-select the ones you want to delete rather than comma-select them.)

 

-CutPlane ( with nothing selected)... If you can maneuver the plane between the two rings you want to inbetween it will add a spline ring at the intersection points. This one does not do "maintain curvature", it leaves the biases as they were which will make for some slight shape change. CutPlane can occasionally get confused on complex spline rings or rings where the CPs were not made in consecutive order.

[John Bigboote]

I tend to do this operation a lot as well (adding a spline ring) my method is to one-by-one select a spline and use the 'Y' key to add an intermediary CP, then connect them myself.

[largento]

Yeah, it doesn't sound like there's anything that does what I'm looking for.

 

I normally do it the way Matt describes, but that results in interrupting the curve and requires I adjust them. Holding-A while adding the CPs avoids this, but it's hard to get the points to line up on a plane, since you're just eyeballing it ...and when you try to correct them, you end up breaking the curve again.

 

I suppose if your regularly work with the bias handles, that's not an issue, but I almost always keep them turned off.

 

I've made thousands of models without having a tool like this. I just wanted to make sure there wasn't one that I was unaware of.

[robcat2075]

Here is a demo of the SplitPatch solution...

 

Inserting a spline between two other splines with SplitPatch

[largento]

Bravo!

[John Bigboote]

Another great solution by Robcat... not automatic too much, but clever. I think the real issue here is... Largento, you need to get accustomed to using your bias handles, dude!

[largento]

Never! :-)

 

Yeah, that's something I've mostly steered clear of due to having made a mess of them when I was first learning A:M. Being an old Adobe Illustrator user, I thought they worked like the path handles in AI. It doesn't take much unknowledgeable fiddling with them before suddenly your splines start to act in very uncool ways.

 

I did use it correctly on a recent model. I needed to make a circular wall with arched doorways and realized that I could get the look I wanted by changing the in and out amounts. But that was for something static that didn't need to bend or move.

[robcat2075]

The behavior of any default bias is to be parallel to an imaginary line between the next and previous CP on the spline. Bias alpha and gamma adjustments are like offsets from that imaginary line.

 

If the next or previous CP is moved across that line, a non default alpha or gamma bias will flip to maintain the same offset to the imaginary line as before.

 

However, that is only in the modeler, where you do want the bias to truly represent its offset to the imaginary line.

 

Bias "flipping" (if that's what we are talking about) is normal in the modeler, but is prevented from happening in animation. If there is a case where biases flip in animation that would be something to look at here.

 

To avoid annoying bias flipping in the modeler, do bias adjustments last in your workflow, after you are fairly certain your CPs are as best placed as they can be.

[largento]

Mostly my issues early on were trying to figure out how to undo what I had done. I didn't understand continuity at the time (I didn't understand much of anything at the time.)

 

I've probably cheated in using them (without actually using them) by making shapes in Adobe Illustrator and bringing them in to A:M as parts and pieces of my mechanical models, but for the most part, I've not needed them.

[robcat2075]

If you're doing what you're doing without needing bias adjustments... keep doing what you're doing! It looks great!

[Rodney]

If you're doing what you're doing without needing bias adjustments... keep doing what you're doing! It looks great!

 

Yes! Most folks would not be able to create models like you do even with Bias adjustment!

(of course this does make me wonder what awesomeness you'd create *with* bias adjustment)

[robcat2075]

I'll note that Mark has noted before that he wasn't using bias adjustments and that has motivated me to depend on them quite a bit less which has led me to making better meshes overall.