[Open Beta] Procedural On-the-Fly Animation in UE4: iTween!

Thank you for the kind words! I’ll be sure to PM you when I’m able to put the fix in!

Hey everyone! 4.26 just released, so here’s iTween for 4.26!


Hi, I’ve been trying to use this plugin to create a more advanced weapon sway, using the ease in and ease out elastic. Everything works when I use set relative rotation, other wise when I use component rotate from the weapon just starts glitching out stuttering and rotating everywhere crazy. I also thought maybe doing it with the Float from too node but theres no way to get the output of the float. I would greatly appreciate any help!

iTween may not handle component relative rotations super well in certain situations. It’s something I would like to fix one day if I ever have a free moment I wouldn’t mind spending in a dev environment. You might try to experiment with the Shortest Path parameter or try using transform rotation to do everything in world space. But otherwise I can help you out with data tweens.

In the image below, you can see me kick off a float tween. On update, we call FloatTweenUpdate which gets an actor of class and updates its relative rotation using a value from the DTV struct.

To accomplish this, set up the tween as normal. If you’re using the Full node, add a function name that will be called on update into the “On Tween Update Function Name” field. If using the Simple node (pictured) type oufn = {function name} into Parameters. oufn of course stands for “on update function name.” Both of these nodes accomplish the same things, this is just a quicker way.

I didn’t do this in the picture, but you’ll also need to plug something into the “On Tween Update Target” pin. This is the object that has a function named the same as what you put into the “On Tween Update Function Name” field. In this case since the same blueprint calls the tween and the target function, we’d plug in “Self” here.

Finally, in the target function we need to access the float data from the tween. To do so, get the iTween Actor reference from the Return Value of the float tween and search for “Data Type Values”. This should return a struct. Split the struct and get the float from it.

You can do this same kind of thing for any data tweens. You may have luck doing a data tween with a rotator or vector if need be. Try some different stuff. Sorry for the inconvenience there!

That was extremely helpful information, hopefully I can use tween to add eleasticity to my floats and plus them into either interp or set rotation. I’ll be experimenting with it. Thank you for the help, and the plug-in is awesome as well!


4.27 version is found here: - Google Drive

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