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Light Streaks-Break up

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Lincoln Waldron
Light Streaks-Break up
on Feb 15, 2011 at 11:07:26 am

Hi
I was wondering if anyone could help me achieve the affect posted in the below picture?
I am trying to get a light streak affect to trail using Trapcode Particular.
I am using Trapcode and I can achieve a solid streak, which looks ok, I just cant achieve the broken up streak like in the picture/Video.
I have viewed every tutorial available (Andrew Kramer).

Would really appreciate your help- thanks for your time.

L

Image:http://i1.creativecow.net/u/92639/sm/screenshot2011-02-15at10.59.08.png


Video:
http://www.niklasjohansson.com/Webbplats/nike.html



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Graham Macfarlane
Re: Light Streaks-Break up
on Feb 15, 2011 at 12:15:30 pm

Have you tried animating the emitter particles per second either manually or via the wiggle expression?

Note; The wiggle expression alone would not easily give you the effect seen in the image. You would need to add some conditionals to the expression to cut off values above or below certain thresholds to get a more on or off look instead of soft disruptions to the glow lines.

Let me know if you need more info on the conditionals.

Graham Macfarlane
3D animator and VFX specialist
London UK


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Lincoln Waldron
Re: Light Streaks-Break up
on Feb 15, 2011 at 1:37:21 pm

Ok thanks, Im not too sure about "conditionals".
Would you mind giving me some more info about this please?
Thanks

L



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Graham Macfarlane
Re: Light Streaks-Break up
on Feb 15, 2011 at 3:18:41 pm

Conditional are programming statements that setup a condition to be tested which either returns true or false. From this you can control program execution.
For example:

Alt click (windows) the stop watch on the Trapcode particulars particles per second field and paste this into the expression box.

pps=wiggle(1,100)
if (pps>20){
100;
}
else{
0;
}


pps is just a variable we've created to contain our wiggle value.
Next there is an if statement to test if pps's value is above a certain point. If it is then the result from our code is a particles per second rate of 100 if not then its zero. Critically there are no in between values.

Animate Particulars emitter around to see the particles come on and off.
Play with the numbers to achieve different spacing of lines and gaps.

Enjoy!

Graham Macfarlane
3D animator and VFX specialist
London UK


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Lincoln Waldron
Re: Light Streaks-Break up
on Feb 16, 2011 at 5:52:06 pm

Thanks so much for your help with this.
I really appreciate it.

L



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