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Technical Discussion » H16 HQueue displaying funny.
- lloydwood
- 104 posts
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Technical Discussion » Flag simulation
- lloydwood
- 104 posts
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So this one should be easy, right? But I'm having a really hard time getting anything that looks at all realistic.
I just want a realistic looking flag sim but I can't get the wind force to give me anything close. I've attached my file. I did a flag in Maya with nCloth in very little time and got something pretty decent but I just can't seem to replicate it in Houdini.
This is the nCloth sim I'm trying to replicate:
https://vimeo.com/179880352 [vimeo.com]
I have looked at and followed the tutorial in the help docs but I don't seem to be getting the same results.
Any pointers would be greatly appreciated.
I just want a realistic looking flag sim but I can't get the wind force to give me anything close. I've attached my file. I did a flag in Maya with nCloth in very little time and got something pretty decent but I just can't seem to replicate it in Houdini.
This is the nCloth sim I'm trying to replicate:
https://vimeo.com/179880352 [vimeo.com]
I have looked at and followed the tutorial in the help docs but I don't seem to be getting the same results.
Any pointers would be greatly appreciated.
Technical Discussion » Crowd path following.
- lloydwood
- 104 posts
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Is it possible to have agents in a crowd stay on piece of geometry without wandering off it?
The only way I have managed to make this work is by generating geometry around the path which acts as an obstacle for agents to avoid. Unfortunately, this doesn't really work very well with more complex geometry with a lot of narrow paths. Also the agents sometimes randomly manage to walk through the obstacle even if the avoid behaviour is their highest priority.
Is there a better way to make sure agents do not leave the boundaries of a piece of geometry? The goal I am aiming for is a crowd which walks/wanders along the pavements in a city respecting the bounds of those pavements.
The only way I have managed to make this work is by generating geometry around the path which acts as an obstacle for agents to avoid. Unfortunately, this doesn't really work very well with more complex geometry with a lot of narrow paths. Also the agents sometimes randomly manage to walk through the obstacle even if the avoid behaviour is their highest priority.
Is there a better way to make sure agents do not leave the boundaries of a piece of geometry? The goal I am aiming for is a crowd which walks/wanders along the pavements in a city respecting the bounds of those pavements.
Technical Discussion » Alembic export camera error
- lloydwood
- 104 posts
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Technical Discussion » Alembic export camera error
- lloydwood
- 104 posts
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I seem unable to export a camera with the Alembic ROP.
I just get the error:
Invalid index provided to getTimeSampling
I'm pretty sure this is to do with the setup I am using. I have a point which has been baked out with N and up vectors. I've then got a rivet which is attached to this point and the camera is parented under the rivet.
Is there a way to get this to export correctly. I've attached the file.
I just get the error:
Invalid index provided to getTimeSampling
I'm pretty sure this is to do with the setup I am using. I have a point which has been baked out with N and up vectors. I've then got a rivet which is attached to this point and the camera is parented under the rivet.
Is there a way to get this to export correctly. I've attached the file.
Technical Discussion » Make crowd switch randomly between states
- lloydwood
- 104 posts
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It's working great! Thanks again for the help.
For anybody who's interested this is the VEX I am running in a sop solver to change the clip assignment after the clip has played through once:
float cliplen = 0;
int cur_clip = 0;
if (@crowdtransition == 0){
if ((f@cliptimes + 0.1) > (agentcliplength(geoself(), 0, s@state)-@TimeInc)){
// This bit ensures the same clip isn't picked again
cur_clip = i@stand_clip;
while (@stand_clip == cur_clip){
@stand_clip = int(fit01(rand(@id), 0, 5));
}
}
}
For anybody who's interested this is the VEX I am running in a sop solver to change the clip assignment after the clip has played through once:
float cliplen = 0;
int cur_clip = 0;
if (@crowdtransition == 0){
if ((f@cliptimes + 0.1) > (agentcliplength(geoself(), 0, s@state)-@TimeInc)){
// This bit ensures the same clip isn't picked again
cur_clip = i@stand_clip;
while (@stand_clip == cur_clip){
@stand_clip = int(fit01(rand(@id), 0, 5));
}
}
}
Technical Discussion » Make crowd switch randomly between states
- lloydwood
- 104 posts
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Technical Discussion » Make crowd switch randomly between states
- lloydwood
- 104 posts
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I have a crowd that's standing around in groups. Each agent has a set of states ( stand, weight shift, arm gesture, etc.). I want the agents to randomly change between these states, play the state through once and then switch to another random state but I can't figure out how to do this with the trigger system. A bonus would be if I could weight the chance of picking certain states e.g. 60% weight shift, 40% arm gesture.
Any pointers would be great.
Any pointers would be great.
Technical Discussion » Deform spiral with curve
- lloydwood
- 104 posts
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That's exactly what I'm after and I like the approach too. I was too set on trying to deform the other shape rather than building a new spiral around the curve. Thank you very much for your help.
Technical Discussion » Deform spiral with curve
- lloydwood
- 104 posts
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I have a spiral and I have a curve. I want the spiral to be deformed by the curve keeping the curve in the same position and keeping the shape of the spiral - so the spiral spirals around the path of the curve. I'm sure there is a simple solution to this but I just can't seem to figure it out.
Any help would be appreciated.
Any help would be appreciated.
Houdini Indie and Apprentice » How to Dop import a dynamic fracture
- lloydwood
- 104 posts
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Hello,
I am struggling with using the dopimport to bring in a dynamically fracturing sim from dops.
I can get the sim to come in if I point the dopimport to the configure fracture node but this means only the fracture appears and the object is not imported until it fractures.
I can fix this by using a switch node to switch from the non-fractured object to the dopimport on the frame that the fracture occurs but this is not at all dynamic.
What is the correct way to do this?
Thanks.
I am struggling with using the dopimport to bring in a dynamically fracturing sim from dops.
I can get the sim to come in if I point the dopimport to the configure fracture node but this means only the fracture appears and the object is not imported until it fractures.
I can fix this by using a switch node to switch from the non-fractured object to the dopimport on the frame that the fracture occurs but this is not at all dynamic.
What is the correct way to do this?
Thanks.
Houdini Indie and Apprentice » Specify RBD collisions
- lloydwood
- 104 posts
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Quick update.
I found a better way to specify collisions. Saw it on a Peter Quint tutorial: http://vimeo.com/15490394 [vimeo.com] - merge everything together with a merge node set to No Change and use Collide Relationship nodes to spell out the collisions.
I found a better way to specify collisions. Saw it on a Peter Quint tutorial: http://vimeo.com/15490394 [vimeo.com] - merge everything together with a merge node set to No Change and use Collide Relationship nodes to spell out the collisions.
Houdini Indie and Apprentice » Specify RBD collisions
- lloydwood
- 104 posts
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Thanks Joker. The merge node setups aren't entirely intuitive but your file has pointed me in the right direction.
Houdini Indie and Apprentice » Specify RBD collisions
- lloydwood
- 104 posts
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Hello,
I have a DOP network with two RBDs (Sphere 1 and Sphere 2), a static terrain and a FLIP fluid tank. These objects all collide with each other in the default setup. What I would like is for Sphere 2 to only collide with the FLIP fluid and ignore everything else. I also want everything else to collide with each other but ignore Sphere 2. I found the collide label and no collide dops but couldn't make sense of how to use them or whether they were the right thing to use. What the best way to go about this?
Thanks.
I have a DOP network with two RBDs (Sphere 1 and Sphere 2), a static terrain and a FLIP fluid tank. These objects all collide with each other in the default setup. What I would like is for Sphere 2 to only collide with the FLIP fluid and ignore everything else. I also want everything else to collide with each other but ignore Sphere 2. I found the collide label and no collide dops but couldn't make sense of how to use them or whether they were the right thing to use. What the best way to go about this?
Thanks.
Houdini Indie and Apprentice » Scale particles that have collided
- lloydwood
- 104 posts
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After much trial, error and help reading I managed to solve this with a VOP SOP network that wrangles my pscale.
The pscale starts at 1. If a particle has stopped (collision behaviour) and has a hittime less than the particle age, the following maths is used to generate pscale: 1/(age-hittime). This causes the pscale to decrease and shrink my copied geomerty accordingly.
Got there in the end.
The pscale starts at 1. If a particle has stopped (collision behaviour) and has a hittime less than the particle age, the following maths is used to generate pscale: 1/(age-hittime). This causes the pscale to decrease and shrink my copied geomerty accordingly.
Got there in the end.
Houdini Indie and Apprentice » Scale particles that have collided
- lloydwood
- 104 posts
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Hello,
I have a particle system that is raining particles from a source down onto a collider. The particles have instanced geometry whose scale is controlled with pscale.
The behaviour I am looking for is for the pscale to remain at 1 until a particle collides. At this event the particle stops and pscale should scale down from 1 to 0 using the particle's age. I have tried but can't get the correct expression or maybe I'm going about it wrong.
I have attached my attempt. Any help would be gratefully received.
I have a particle system that is raining particles from a source down onto a collider. The particles have instanced geometry whose scale is controlled with pscale.
The behaviour I am looking for is for the pscale to remain at 1 until a particle collides. At this event the particle stops and pscale should scale down from 1 to 0 using the particle's age. I have tried but can't get the correct expression or maybe I'm going about it wrong.
I have attached my attempt. Any help would be gratefully received.
Houdini Indie and Apprentice » Particle emission / parent issue
- lloydwood
- 104 posts
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Thanks Joker!
This is exactly what I was looking for. Really well commented too.
Thanks again for your help.
This is exactly what I was looking for. Really well commented too.
Thanks again for your help.
Houdini Indie and Apprentice » Particle emission / parent issue
- lloydwood
- 104 posts
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This is probably a very basic question but here we go.
I have a box which has animation on it at the object level. I have a separate object with a popnet in it. The popnet has a location emitter with some gravity and drag attached. The emitter is emitting in the X-axis.
The behaviour I want is for the emitter to emit along the X-axis of the animated box but I then want the particles to be free to be pulled down by the gravity i.e. I don't want the whole particle system to move with the animation of the box. The particle should shoot off along the vector the x-axis was pointing down on the frame that particular particle was emitted.
I can't figure out how to do this. Any help would be gratefully received. My mind's not quite in that Houdini place yet!
I have attached my not working at all file.
I have a box which has animation on it at the object level. I have a separate object with a popnet in it. The popnet has a location emitter with some gravity and drag attached. The emitter is emitting in the X-axis.
The behaviour I want is for the emitter to emit along the X-axis of the animated box but I then want the particles to be free to be pulled down by the gravity i.e. I don't want the whole particle system to move with the animation of the box. The particle should shoot off along the vector the x-axis was pointing down on the frame that particular particle was emitted.
I can't figure out how to do this. Any help would be gratefully received. My mind's not quite in that Houdini place yet!
I have attached my not working at all file.
Houdini Indie and Apprentice » How to go about optimising a volume render
- lloydwood
- 104 posts
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Wow. Micropolygon has made a big difference. I'm not sure why I switched to ray tracing in the first place :?
Are there any other adjustments that can be made other than the volume step size to improve thing even further? Light settings etc?
Are there any other adjustments that can be made other than the volume step size to improve thing even further? Light settings etc?
Houdini Indie and Apprentice » How to go about optimising a volume render
- lloydwood
- 104 posts
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Hello,
I have a scene that has a volume with a fractal applied to it to create a cloudscape. I am trying to optimise the frame render time for this scene but am unsure where to start. I know about volume step size and have tried messing with it but still have huge frame times. To be honest I'm unsure what a reasonable frame time for this type of render would be on my machine (i7 950 3.07Ghz).
Any pointers/advice would be greatly appreciated. I'v attached the file too.
EDIT: added the otl also
I have a scene that has a volume with a fractal applied to it to create a cloudscape. I am trying to optimise the frame render time for this scene but am unsure where to start. I know about volume step size and have tried messing with it but still have huge frame times. To be honest I'm unsure what a reasonable frame time for this type of render would be on my machine (i7 950 3.07Ghz).
Any pointers/advice would be greatly appreciated. I'v attached the file too.
EDIT: added the otl also
Edited by - 2012年4月6日 06:49:31
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