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Kinect - DX11Particles Hide Source Emitter?

Hey Everyone :D

Here’s something (that I imagine is really simple) that I don’t understand; how to hide/disable the original Emitter particles in (for example) the Kinect - dx11particles.v4p patch?

I’d like to only see the spawned particles from the EmitterRwStructuredBuffer Emitter, and not a mix of both.

Disconnecting the EmitterKinect from the group kills everything, how come? Isn’t the Emitter(dx11.particles.selection) already “linked” to it (not sure what to call this, it’s invoking it?)

Does the group node pass information “upwards” as well? If so, why can’t I run a second connection from the selection node, right into the particle system node?

Is there any video tutorials/workshops on the topic I may have missed?

Thanks for any help :D

For anyone else in my shoes :D

This helped: https://www.youtube.com/watch?v=qhfZyZnKB7U

I added a Selection(DX11.Particles.Selection) node to the group. Gave it the Emitter(DX11.Particles.Selection) node and specified the EmitterKinect in the Emitter Name pin. Finally I added a Kill(DX11.Particles.Modifiers) node to the Selection.

New issue; now there’s some weirdness happening near the top. Any ideas?

I believe it’s a combination of max particle count and lifetime. looks like some points are drawn twice and therefore distorted, because they originate from different kinect frames.

@schlonzo interesting!

I looked inside the Kill node and (it seems to me) it’s a lifespan modifier set to -1.

Still can’t seem to get it to just give me the modified particles only :(

Are there any other methods of removing the originals and just keeping the newly spawned particles anyone know of?

Thanks :D

you have a selection with an emitter on the modifier input. I don’t know if that works although you can connect it. I believe you should just connect nodes that explicitly say “modifier” in the nodebrowser.

I see you use a mod on the resolution… If you want to emit like a checkerboard you can simply multiply the world texture with a checker board…

what effect are you trying to achieve?

This is from the Kinect Girlpower Patch, so my assumption was whoever made it knew what they were doing :P

If I understand the patch correctly, the original goal is to spawn particles with a 5 second lifespan from the Kinect ones (which have a 0 second lifespan and cannot be modified) then apply a force to them…

In order to cut down on particle count, the patch employs a Modulo to only spawn 5 second life particles here and there, as opposed to all the kinect ones…

My attempt was to keep the longer lifespan particles but remove the original kinect ones, the ones with a much higher density (although not lifespan.)

My screencap shows what happens when I try this out; the kill node does eliminate all the original kinect particles, the second emitter successfully emits long lifespan particles at reduced resolution but there’s that weird artifact at the top :(

I though this was the mod being used on the emitter, not the resolution, maybe my jargon is inadequate :P

I was under the impression that the Kinect node is outputting a particle resource (not sure if this is the correct name for this), not a texture. But I’ll add the file and maybe that would make it easier for you to explain. Help much appreciated :D

Kinect - dx11particles.v4p (26.0 KB)

You have to know your maximum emitter size, how many particles you emit and when! you emit them, as well as their lifetime. The emitter will just emit new particles if there are fewer particles alive than the max emitter count.

For example, you emit kinect2 (512x424 = 217088 particles) that would be your max emitter size AND the count of the particles you spawn if you want to show one kinect frame. They also have to have a lifetime of 0.0333 (1sec / 30 fps), so that all particles die, before the next kinect frame gets emitted.

I suggest you dig through the emitter and advanced emitter help patches until you feel you have total control of what’s happening. otherwise its quite difficult to pinpoint where a glitch comes from.
Watch out that if your dynamic buffer does not match the particle count, vvvv will loop the buffer in spread logic. (1,3) = (1,3,1,3,1,3…)

To modify the emitter lifetime you can simply group the kinect emitter with a lifespan modifier to set the lifetime of your kinect particles.

Keep in mind that the input for the kinect emitter is just a texture (16bit precision vs 8bit standard texture). If you want to perform 2D operations on the pointcloud that’s the more performant way to go…

hope that helpsDesktop.7z (3.6 KB)

cheers