groups pieces from points

[csp]

I have a scene where geometry is pre-fractured using voronoi, and I have assigned one point to the center of each piece and then I am sending the points to POP network for animation. in order to animate the pieces I have a sphere/trigger as a bounding object and every point/piece is included will be animated using some forces. The problem is back to sop network, I want to group the pieces, not the point, but the piece which are selected/animated.

if you open the hip you will see that, all I want is to import the final mode of the "street" geometry to debris and dust. Because of voronoi fracture tool, it give me already the two useful groups (inside, outside) of each piece. But I want somehow to end up with one more group, all the piece ta actually moving. It has to be updated as the sphere/trigger is moving and new pieces moving. I need that in order to have the right piece emit debris and dust in the right time.

lineCrackingGround_0012.hip

[Emanuele Berti]

Hi,

what you could do is to add an attribute that stores the points' velocity and then, thanks to the copy SOP you already have,

group together the primitives copied to the points with velocity different from 0.

If you want to emit your dust just during the first two frames (in your POP network when the particles go up) you could use >0 instead of != 0 in the group expression.

Cheers,

Emanuele

lineCrackingGround_0012_movingGrp.zip

[csp]

Hi,

what you could do is to add an attribute that stores the points' velocity and then, thanks to the copy SOP you already have,

group together the primitives copied to the points with velocity different from 0.

If you want to emit your dust just during the first two frames (in your POP network when the particles go up) you could use >0 instead of != 0 in the group expression.

Cheers,

Emanuele

thanks Emanuele for your reply,

for some reason never got an email notification about your reply so, I thought nobody get back to me. I am gonna check your attached hip and let you know how works for me. What you wrote makes perfect scene, I am try to get used the attribute creation, are very useful. Thanks again.

Edited December 13, 2010 by cparliaros

[csp]

If you want to emit your dust just during the first two frames (in your POP network when the particles go up) you could use >0 instead of != 0 in the group expression.

Your setup in my scene was great, but I am facing only one small problem. As the particles are moving, there are in the group, but once they stop moving they are leaving the group, and along with them smoke and particles from this primitives are disappear.

How can I preserve the group, in group POP has this option, but I can find something similar for the group SOP.

I was thinking that I have already a group in inside the popnet which includes all the points that are moving or have been moved. When I am in sop level, the group exists until meets the copy sop which keep only groups from the left side. Is there any way to use this, or maybe I can change the color of these particles in the pop level and as the accel attribute, is there any attribute which carrying the color info of the particles?

Edited December 13, 2010 by cparliaros

[Emanuele Berti]

I want somehow to end up with one more group, all the piece ta actually moving.

As the particles are moving, there are in the group, but once they stop moving they are leaving the group

That's what I thought you were after, I'm not sure I'm still following you...

and along with them smoke and particles from this primitives are disappear.

That shouldn't happen... if you emit from that group and the group at some point in time has no primitives/points in it... it should just stop to emit new smoke/dust.

Try to check how your setup works and if you don't find anything strange, try to publish the scene, hopefully someone will help you.

Cheers,

Emanuele

[csp]

That shouldn't happen... if you emit from that group and the group at some point in time has no primitives/points in it... it should just stop to emit new smoke/dust.

Try to check how your setup works and if you don't find anything strange, try to publish the scene, hopefully someone will help you.

Enanuele thanks again for the help, I managed to have debris coming from the cracks using your set-up with the accely attribute. You were right that it does not delete the already created particles even if the piece is out of the group, it just stops emitting more particles from the stopped pieces, which is good.

Now I am missing the final piece of the puzzle, the dust which has to coming from the cracks as well. For some reason it does not. I am not sure if this has to do with the group which hold the moving pieces or with the smoke set-up in dops. I am using exactly the same set-up, successfully, when I want to emit smoke from object which using the auto-shatter tool, Make Breakable. I though it will work with pre-shattered objects but it does not.

For anyone who can help, I have attached the new improved hip file. Also I am going to include the hip files which using the same set-up for emitting smoke from not pre-shuttered objects. It is not so much about the solution, mostly is about why this is happening... I would like to know.

Cheers

Christos

lineCrackingGround_0012.hip

autoshatter_emitSmoke.hipnc

[Emanuele Berti]

Hi Christos,

I had a look to your scene and I believe your problem is that you don't have a source DOP in your flow.

Click on "Source from Volume" inside the Volume Fluids shelf, then select geo_for_smoke OBJ and press enter, then select the smoke container in your view and press enter again.

Now you have a source DOP in your flow and you should see your smoke been emitted from the volume you just created with the isooffset in the geo_for_smoke node.

Cheers,

Emanuele