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DaJuice

Inherit Velocity not working?

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This should be simple but I can't get it right. Here is a simple network I made, and the attribute stuff is set up like in the POP video turorial, but mine isn't working. What the heck am I over-looking??

simplepop.zip

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Without looking at the file, just some info:

Whats a pitfall about the Inherit Velocity is that it'll use the "v" attribute OR the "N" attribute on your geometry. I cant remember offhand which one takes precedence (I think N), but that can trip you up pretty easily. If the Source POP had a option to choose which one to use, it'd be a little clearer, but you may as well just use try one or the other.

I hope this actually is the reason:)

J.

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Thanks for the fast response Jason.

Ok, the source geometry is a null in this case. I appended a Point SOP and added Normal and Velocity attributes and I pointed the Source POP at this SOP. In the attribute page I chose either v or N but neither are working. They are spawning correctly from the null but the only thing affecting their motion is the Force POP I have.

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Thank you chang, but how do you do this without overwriting the animation with an expression?

I'd still like to know what was wrong with my file...

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*bump*

Nobody knows what's wrong with my file? :(

To show that I'm not trying to waste anybody's time, here is what I'm working on at the mo...

(divx5.0.2, 320x240, 4sec, 139kb)

http://dajuice.t35.com:8000/files/walk.avi

Ignore the crappy walk cycle and shaders, the problem is the fireballs. Well it's not really supposed to be fire, more like some kind of semi-liquid acid goo. Anyways, without inherit velocity working the motion looks pretty bad as you can see.

post-21-1063088186.jpg

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The point SOP only adds attributes and sets them to the specified value. It doesn't actually compute the velocity. For this, try the trail SOP. The problem appears to be that you're inheriting a velocity of 0, 0, 0.

Hope this helps...

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I must be brain dead, I just can't get this to work. I apply a Trail SOP, set 'Compute Velocity' and pick the Trail SOP as my source geometry in POPs. Leave inherit velocity page at defaults, nothing. Change the scope to v only, nothing. This is driving up the wall, what else can I do? :wacko:

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The Trail SOP computes velocity based on changing *geometry*. So what I did was create another object, Object Merged in your null_model and set the Transform Object to dot (.) This essentially brings your object-level animation into the SOP world. So append your Trail sop to this with compute velocity and use it as your source geometry in the source pop.

PS. A way to see this is to go into the SOP level for your null_model object and turn off the See All button. Now hit play. Note that there's no animation.

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Halleluya, we have a winner! :D Thanks once again Edward (and everyone else too) and thank you for the nice comments.

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