MoGraph arrow head alignment problem

[Jack Evans]

Hmm… I still can’t get that poke-through fixed. Not sure what I’m doing wrong (again, complete C4D noob here) but it won’t accept any changes to the P.Z value for the cloner object at any frame. I change the value, then it blinks back to what it was before. I can change the position value of the arrow head object, but that doesn’t do anything; the sweep object continues to follow it. It looks like the end of the sweep object is tied to the center of the arrow head; I’m wondering if the sweep were following a null object parented to the arrow head, if it would work differently.

I’m ordering the live version this week, I’ll try it again once it arrives (maybe there’s a patch that covers it that didn’t make it into the demo). Since the problem is reproducible and the scene file here is pretty basic, I would think it wouldn’t be too hard for the engineers to track down if someone sends in a bug report.

[John Hammond]

Hi Jack,

The Arrowhead’s positions are firstly arranged in a radial pattern by using the Cloner Object (mograph). This cloner then flies around the circlePath through the use of the Align to Spline tag on the cloner. (animating position %).

To adjust the arrow’s position you can alter the original object’s pivot point, or add a plain effector to the cloner and adjust the position params.

However, I don’t think this issue is related to the crazy render I am getting . . the geometry is jumping around all over the place (see render above).

[Jack Cook]

John, I don’t know if this is exactly what you’re looking for, but here’s a tutorial about how to make an object follow the growth of a sweepNurbs object. I’ve used this to make an arrow grow in a similar way to what happens in your file.

Jack

[Jack Cook]

I forgot to put in the link. Here it is:

https://www.base80.com/index.php/2007/01/29/align_to_spline_xpresso#more1

Jack

[John Hammond]

Cool, thanks JAck. I’ve use Xpresso a little like this tuts first example.. But this tut goes deeper with the vector2matrix and matrix to HPB.. I need to work through that and try to understand it!

Cheers.