View Full Version : Keeping particles looking the same size

07 July 2012, 08:22 PM
Is there a way to keep particles/thinking particles/spriticles the same visual size, no matter their position in Z space?

07 July 2012, 06:49 AM
You can easily scale TP based on distance to camera.

07 July 2012, 07:53 AM
1. get distance between camera and particle/sprite
2. rangemap (to rescale particle-size regarding to distance)
3. set particle size

the only little tricky part will be to set the size 100% exactly.
good luck

07 July 2012, 09:21 AM
If the distance doubles the size needs to double as well. With this formula it should be pretty straightforward to get a 100% match.

07 July 2012, 06:05 PM
I'm using PMatterWaves to generate the particles. PShape to determine the geometry used for each particle.

I'm assuming I link MatterWaves Particle Birth to PScale? Link it to my camera's Global Position somehow?

My Xpresso skills aren't fantastic and my TP skills are even less. I'd really appreciate some more detailed guidance if anyone has a free moment. Look at the screenshot... I'm getting close, maybe?

07 July 2012, 10:45 PM
Particle Birth is only evaluated once, at birth.
You need to use PPass to evaluate and make changes to your Particles over time.

You can link the PPass to a PGetData Node to continually get each Particle's Position.
You compare that Position with the Camera Position (Distance Node), and set up the resizing like you already did, that's fine.
Don't forget to connect your PSize node to the PPass.

That should get you up and running.


07 July 2012, 06:25 PM
Is this close?

07 July 2012, 07:57 PM
Is this close?
yep ;)

The rest should be a matter of tweaking Range Mapper Settings, I would guess

07 July 2012, 07:57 PM
Having a bit of trouble getting my brain around PSize's Size and the relationship with PShape's Bounding Radius.

Do they have anything to do with Cinema's units? My PShape is a 2cm sphere. What units are Bounding Radius? And the number I'm feeding into PSize... is that pixels? xyz scale?

I feel like I'm just plopping in arbitrary numbers and seeing what the render gives me. :cry:

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07 July 2012, 07:57 PM
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