Jump to content
sphirus

particles problem

Recommended Posts

Hi, I need some help in particles. I'm currently doing the effects the particles forming the building shape and after awhile the particles will fall down procedurally by the affection of the gravity. With the help of "attributetransfer" node, I actually did the front part. But somehow the later part actually not what i want because the particles still birth at the group place. I'm not sure I'm saying the right thing so will attach my file here. New to houdini, need help :(

building_form.hipnc

Share this post


Link to post
Share on other sites

Hi, I need some help in particles. I'm currently doing the effects the particles forming the building shape and after awhile the particles will fall down procedurally by the affection of the gravity. With the help of "attributetransfer" node, I actually did the front part. But somehow the later part actually not what i want because the particles still birth at the group place. I'm not sure I'm saying the right thing so will attach my file here. New to houdini, need help :(

building_form.hipnc

anyone can help me? :(

Share this post


Link to post
Share on other sites

Use Impulse Birth if u don't want constant particle creation OR use if() expression to stop birth of particles in desired frame.

Share this post


Link to post
Share on other sites

Use Impulse Birth if u don't want constant particle creation OR use if() expression to stop birth of particles in desired frame.

Actually i did use the impulse birth but the group that i use to emit the particles still doing the same thing(emit particles). I use "$NPT" in it. What I'm doing in my file is the particle will emit on the surface first. Later, I use "attributeTransfer" node to color the particles in blue. After that, I create a group sop to collect the blue point and append a pop net to it. This pop net will use my group point to emit particles. And the delete node will connect to it also to delete that group point. So, the result should be the particles become blue and disappear and pop net emit particles on the disappear place. But, somehow after my group all be deleted but my particles still emit at the birth place. How can I control the particles just emit once? Thanks :unsure:

Share this post


Link to post
Share on other sites

Actually i did use the impulse birth but the group that i use to emit the particles still doing the same thing(emit particles). I use "$NPT" in it. What I'm doing in my file is the particle will emit on the surface first. Later, I use "attributeTransfer" node to color the particles in blue. After that, I create a group sop to collect the blue point and append a pop net to it. This pop net will use my group point to emit particles. And the delete node will connect to it also to delete that group point. So, the result should be the particles become blue and disappear and pop net emit particles on the disappear place. But, somehow after my group all be deleted but my particles still emit at the birth place. How can I control the particles just emit once? Thanks :unsure:

Anyone can help me on this improvement? Most appreciated

Share this post


Link to post
Share on other sites

Actually i did use the impulse birth but the group that i use to emit the particles still doing the same thing(emit particles). I use "$NPT" in it.

First, yes, so you are using $NPT (Number of particles) ... in "Const. Birth Rate" so it's constantly emitting $NPT of particles.

Second, You have two pop networks in Your tree (with $NPT as Constant birth rate), I'm little bit lost - which one u want to emit once?

Besides, Wouldn't be easier to use this ball as collision for first pop network ?

Share this post


Link to post
Share on other sites

First, yes, so you are using $NPT (Number of particles) ... in "Const. Birth Rate" so it's constantly emitting $NPT of particles.

Second, You have two pop networks in Your tree (with $NPT as Constant birth rate), I'm little bit lost - which one u want to emit once?

Besides, Wouldn't be easier to use this ball as collision for first pop network ?

the second pop network is what i want to emit once actually. What do u mean using the ball as collision? I think the result will be different.

Share this post


Link to post
Share on other sites

Here is the simple file I guess demonstrate your idea, hope it helps.

Hi, nature, thanks for your help. But once I open your file, it caused fatal error and closed automatically. I hope you can attach your file again. Thanks a lot.

Share this post


Link to post
Share on other sites

Hi, nature, thanks for your help. But once I open your file, it caused fatal error and closed automatically. I hope you can attach your file again. Thanks a lot.

I'm sorry about it, This file was created in Houdini 11, so you need the version 11 to open it.

Share this post


Link to post
Share on other sites

I'm sorry about it, This file was created in Houdini 11, so you need the version 11 to open it.

Ok, I will try on it. Thanks for help.:)

Share this post


Link to post
Share on other sites

Ok, I will try on it. Thanks for help.:)

Hi, nature. I'm still can't open your file even using houdini 11. The same problem was occured. Hope you attach your file again. Thanks :rolleyes:

Share this post


Link to post
Share on other sites

Hi, nature. I'm still can't open your file even using houdini 11. The same problem was occured. Hope you attach your file again. Thanks :rolleyes:

Hi, sphirus, I cannot figure out why you cannot open my file, I actually download my own file from this post and open it without any problem. Anyway, I saved new copy here and the fundamental trick is "not use attrib transfer in SOPs but in POPs".

If it still cannot solve your problem, you may check this post here

The fundamental trick is the same. Hope all these can help you. :P

cheers

particleFall_odforce.hipnc

Share this post


Link to post
Share on other sites

Hi, sphirus, I cannot figure out why you cannot open my file, I actually download my own file from this post and open it without any problem. Anyway, I saved new copy here and the fundamental trick is "not use attrib transfer in SOPs but in POPs".

If it still cannot solve your problem, you may check this post here

The fundamental trick is the same. Hope all these can help you. :P

cheers

Hi, nature. Thanks for your help. But I still cannot open your file. Can you describe your idea about "not use attrib transfer in SOPs but in POPs" here? I think if you can add some screenshot of it will help me to understand. Most appreciated. :rolleyes:

Share this post


Link to post
Share on other sites

Hi Sphirus,

I spotted two errors in your flow...

1-in your popnet3 instead of using $NPT/100 in Const. Birth Rate, write $NGRP/100

2-between xform2 and the attribtransfer1, put another color SOP and set the color to black (0,0,0)

Hope that helps!!!

Cheers,

Emanuele

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×