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lowkey
03-04-2003, 09:00 AM
i setup a particle instancer to emit random characters, controlled by an expression i modified from the 'creating matrix logo effect'-tutorial on highend3d.

now, can somebody tell me how to make the instanced geometry rotate on emission (at a random rate) and maybe if i can achive random scaling as well?

i'm not that deep into MEL yet, so any hint might be helpful! :hmm:
alexx
03-04-2003, 10:13 AM
so here the hint:

- you need new per particle attributes (e.g. myScalePP)
- in your instancer settings you have to turn on the toggle "allow all data types"
- now you can choose your own per particle attributes for scaling e.g.
- if you create a creation expression for the myScalePP with e.g.:

particleShape1.myScalePP = <<rand(0,1),rand(0,1),rand(0,1)>>;

you will get a random scaling for each instanced object

cheers

alexx
lowkey
03-04-2003, 10:41 AM
well, that was really helpful, but is there a way to set the instancers' scale parameters even after it has been created?!

i can't find those general attributes in the AE! :shrug:

anyway, thanks a lot! :thumbsup:
alexx
03-04-2003, 12:35 PM
if you want to change sizes for an existing and non-emitting system that has a initial state set on any other frame than 1, you can create a runtime expression, run one frame, delete the expression and set initial state.. that is the fastest way to get there

cheers

alexx
lowkey
03-04-2003, 03:07 PM
yep, it worked! :thumbsup:

thank you very much!
lowkey
03-04-2003, 03:45 PM
one last thing:

i'm controlling randRotatePP by runtime expression, which works pretty well.

anyway, the motion looks kinda harsh and jerky, because the rotation changes every frame.

statements like:

if ((frame % 24) == 0)

force the changes to take place every second, but motion skipping still ruins the effect of smooth floating characters in space.

how can i get a smooth runtime rotation!?
alexx
03-05-2003, 08:21 AM
you can use the particleID to change the rotation behaviour continous..

e.g. something like:

myrotatePP = <<particleId*10+time, particleId*16+time, particleId*21+time>>;

play with the numbers and you might wanna divide the time by a value to slow it down

cheers

alexx
lowkey
03-05-2003, 09:42 AM
yeeeeh, thanks a lot!!! :bounce:

now it's just like i wanted it to be.

damn, i have to get much deeper into MEL... :wip:
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