I've been looking at this myself and I'm equally bemused about Houdini's volumetric renders. Can I ask what your appying the shaders too?
I seem to get the best results using an ISOoffset, so increasing the density does give me noticible results with this SOP.
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Houdini Lounge » Weird problem with smoke shader
- stevecullum
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Houdini Indie and Apprentice » Implicit surface?
- stevecullum
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Thanks - looks pretty interesting!
Look like in that example you have randomised the zero boundary with a noise function or something?
I don't really understand the maths behind volume geometry, so terms like ‘zero boundary’ is a bit lost on me really ops: Perhaps if I find something on that it will help me to know what's going on further.
Cheers!
Look like in that example you have randomised the zero boundary with a noise function or something?
I don't really understand the maths behind volume geometry, so terms like ‘zero boundary’ is a bit lost on me really ops: Perhaps if I find something on that it will help me to know what's going on further.
Cheers!
Houdini Indie and Apprentice » Implicit surface?
- stevecullum
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Thanks for the explanation.
I still don't exactly know what I'm looking at, but I assume looking at the examples these nodes are for building voxel grids and volume based objects then?
I suppose being used to Lightwave Hypervoxels its hard for me to grasp. If your familiar with Hypervoxels, you will know that they create puffy volumes for thick volumteric smoke.
Would I be needing to use one or both of these to achieve a similar effect?
I still don't exactly know what I'm looking at, but I assume looking at the examples these nodes are for building voxel grids and volume based objects then?
I suppose being used to Lightwave Hypervoxels its hard for me to grasp. If your familiar with Hypervoxels, you will know that they create puffy volumes for thick volumteric smoke.
Would I be needing to use one or both of these to achieve a similar effect?
Houdini Indie and Apprentice » My Apprentice experience - one month in
- stevecullum
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Thanks. I got that working, but it would be nice to be able to grab a g_marble and a g_granite and overlay or mix them together in some way. I can't see a way to that though.
Houdini Indie and Apprentice » My Apprentice experience - one month in
- stevecullum
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I'm pretty much at the same point with VEX. No real clue what I'm doing and stumbling about with occasional success :roll:
I just think it should easier to work at a higher level. Combing existing shaders and layering maps and procedurals without stepping into VEX networks. It feels like I got to go deep to get effect taken for granted in other apps - Fresnel, occlusion etc…
Its a shame there isn't that much learning material about for this side of Houdini.
I just think it should easier to work at a higher level. Combing existing shaders and layering maps and procedurals without stepping into VEX networks. It feels like I got to go deep to get effect taken for granted in other apps - Fresnel, occlusion etc…
Its a shame there isn't that much learning material about for this side of Houdini.
Houdini Indie and Apprentice » My Apprentice experience - one month in
- stevecullum
- 112 posts
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Since the start of the Houdini 9 series, its been apparent the efforts Side Effects have gone to, to make Houdini more accessible to artists and for that reason I thought I would write something about my experience over the last month. I've come over from Lightwave and so my entry into the world of Houdini has been an interesting one, to say the least!
Lightwave introduced me to nodes and their potential and I have found working with the nodes in Houdini, comfortable if a bit different. SOPS nodes are fantastic and I'm loving what I've seen of CHOPS so far. The learning curve has been a little steep in some places, but now I'm getting the hang of using channel referencing and expressions, I'm starting to really enjoy myself
DOPS and POPS have been good fun also. So powerful, yet fairly accessible even for a Houdini noob - got to love the rigidbody glue object! The fluid and gas solver stuff is pretty daunting though. While undoubtedly powerful, the number of building blocks you need to make an effect come to life creates a steep learning curve IMO.
SHOPS - this is the hardest and most frustrating bit for me. I'm still hopelessly confused by the shaders. I wanted to wire a vex metal shader and a vex gsplatter together in some way, but couldn't find any information on this. Its seems to take ages to create a surface effect which takes five minutes in Lightwaves node editor.
That's as far as I've seen so far, not explored COPS or ROPS too much yet. So overall, Houdini HD has been the best $100 I spent this year and I'm sure it will continue to bring me hours of fun! But if there is one thing I would change, its the way textures and shaders are accessed. I would prefer to have a higher level access, so I can just plug things in like I can in Lightwave. Of course VEX shader builders should be there for the power user, but IMHO if Side Effects wants to continue attracting new users, then making the shading and rendering side of things easier and faster is perhaps the next area to focus on.
Lightwave introduced me to nodes and their potential and I have found working with the nodes in Houdini, comfortable if a bit different. SOPS nodes are fantastic and I'm loving what I've seen of CHOPS so far. The learning curve has been a little steep in some places, but now I'm getting the hang of using channel referencing and expressions, I'm starting to really enjoy myself
DOPS and POPS have been good fun also. So powerful, yet fairly accessible even for a Houdini noob - got to love the rigidbody glue object! The fluid and gas solver stuff is pretty daunting though. While undoubtedly powerful, the number of building blocks you need to make an effect come to life creates a steep learning curve IMO.
SHOPS - this is the hardest and most frustrating bit for me. I'm still hopelessly confused by the shaders. I wanted to wire a vex metal shader and a vex gsplatter together in some way, but couldn't find any information on this. Its seems to take ages to create a surface effect which takes five minutes in Lightwaves node editor.
That's as far as I've seen so far, not explored COPS or ROPS too much yet. So overall, Houdini HD has been the best $100 I spent this year and I'm sure it will continue to bring me hours of fun! But if there is one thing I would change, its the way textures and shaders are accessed. I would prefer to have a higher level access, so I can just plug things in like I can in Lightwave. Of course VEX shader builders should be there for the power user, but IMHO if Side Effects wants to continue attracting new users, then making the shading and rendering side of things easier and faster is perhaps the next area to focus on.
Houdini Indie and Apprentice » Implicit surface?
- stevecullum
- 112 posts
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I've just been playing about with the ISO surface and ISO offset nodes. I've read the help file on these two, but I don't really understand it.
What's an ‘implicit’ surface and how are these nodes best used?
What's an ‘implicit’ surface and how are these nodes best used?
Houdini Indie and Apprentice » Moving particles along a path?
- stevecullum
- 112 posts
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Houdini Indie and Apprentice » Moving particles along a path?
- stevecullum
- 112 posts
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Doh! - I hadn't considered the MB part. :roll: - and its good point! I tend to use Reelsmart for adding Mblur, so wasn't thinking about it.
Ok so I fixed up this version which is now doing as I hoped and won't mess up any motion blur.
The thing is now though, if I middle mouse over the delete node, it says more and more objects, so is it actually deleting them?
EDIT: Its the copySOP expression I need to work on!
Ok so I fixed up this version which is now doing as I hoped and won't mess up any motion blur.
The thing is now though, if I middle mouse over the delete node, it says more and more objects, so is it actually deleting them?
EDIT: Its the copySOP expression I need to work on!
Houdini Indie and Apprentice » Moving particles along a path?
- stevecullum
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As I continue to explore the various ways to achieve things in Houdini, I'm now trying to recreate this object belt particle effect without using particles!
I have the following expression driving a creep SOP node:
ch(“../xform1/rz”)*0.05/60
It references its motion from a spinning tube so every 60 degrees it moves the objects on the creep by the distance the objects are spaced. What I would like to do is say “everytime the creepSOPS tx channel reaches 0.05, reset tx back to 0 and restart the cycle” thus giving the illusion of a continuous supply of bullets.
I tried an if(ch(“../tx”)>0.05, 0, ch(“../xform1/rz”)*0.05/60) but it fails. I think I know why it fails, but what would I need to do to make this work as intended?
I have the following expression driving a creep SOP node:
ch(“../xform1/rz”)*0.05/60
It references its motion from a spinning tube so every 60 degrees it moves the objects on the creep by the distance the objects are spaced. What I would like to do is say “everytime the creepSOPS tx channel reaches 0.05, reset tx back to 0 and restart the cycle” thus giving the illusion of a continuous supply of bullets.
I tried an if(ch(“../tx”)>0.05, 0, ch(“../xform1/rz”)*0.05/60) but it fails. I think I know why it fails, but what would I need to do to make this work as intended?
Houdini Indie and Apprentice » Moving particles along a path?
- stevecullum
- 112 posts
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I've looked at the bullet_curve example file and its doing exactly what i wanted to happen - so thanks for your help again here.
I looked up in the help what primduv does and sadly I dont understand the explanation. I need to somehow wrap my head around this kind of stuff, so in the future when another issue presents itself I know what I'm supposed to be typing into these channels!
Is there anywhere I can get an idiots guide to Houdini expressions?!!
I looked up in the help what primduv does and sadly I dont understand the explanation. I need to somehow wrap my head around this kind of stuff, so in the future when another issue presents itself I know what I'm supposed to be typing into these channels!
Is there anywhere I can get an idiots guide to Houdini expressions?!!
Houdini Indie and Apprentice » Moving particles along a path?
- stevecullum
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Thanks for the link eetu!
So should I be copying the original curves tangent values or be using the particles tangents?
I have to confess to being a bit dim with all this. I'm used to clicking a button - ‘follow path’ - I guess with Houdini you actually have to understand whats going on! ops:
Do I need the attribute tansfer SOP to copy the normal data to the instances?
EDIT: Doh! - only just saw the attachement Edward - thanks!
So should I be copying the original curves tangent values or be using the particles tangents?
I have to confess to being a bit dim with all this. I'm used to clicking a button - ‘follow path’ - I guess with Houdini you actually have to understand whats going on! ops:
Do I need the attribute tansfer SOP to copy the normal data to the instances?
EDIT: Doh! - only just saw the attachement Edward - thanks!
Houdini Indie and Apprentice » Moving particles along a path?
- stevecullum
- 112 posts
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Thanks! - but its not quite working. I probably messed something up :roll:
I've attached a test of what's happening right now. I just need the tubes to align to the rotation of the particles as they move down the wire.
I've attached a test of what's happening right now. I just need the tubes to align to the rotation of the particles as they move down the wire.
Houdini Indie and Apprentice » Moving particles along a path?
- stevecullum
- 112 posts
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I nearly got everything working thanks to all your help - Cheers!
One last question if I'm allowed
It seems the sweep sop doesn't work with a popnet so I need to use a copy sop to attach geometry to the particles. How do I orient the geometry to align with the motion of the particle normal direction?
One last question if I'm allowed
It seems the sweep sop doesn't work with a popnet so I need to use a copy sop to attach geometry to the particles. How do I orient the geometry to align with the motion of the particle normal direction?
Houdini Indie and Apprentice » Particles - selective dynamics effectors?
- stevecullum
- 112 posts
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Houdini Indie and Apprentice » Particles - selective dynamics effectors?
- stevecullum
- 112 posts
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Is it possible to selectively choose how dynamic objects effect the motion of particles?
I have a stream of particles attached via a Creep node (thanks to Edward for help on this part!) I have now added a wire solver into the mix and I would like the particles to follow the shape of the wire as it flex's with gravity and motion but not to sling the particles off. So I need to say something like
'make particles un-effected by motion, but position is okay!'
I have a stream of particles attached via a Creep node (thanks to Edward for help on this part!) I have now added a wire solver into the mix and I would like the particles to follow the shape of the wire as it flex's with gravity and motion but not to sling the particles off. So I need to say something like
'make particles un-effected by motion, but position is okay!'
Houdini Indie and Apprentice » Moving particles along a path?
- stevecullum
- 112 posts
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hehe…yeah thats the one!
I definitely need help thinking through expressions though, as I was making it far more complex than it needed to be! :?
Thanks for that Edward
I definitely need help thinking through expressions though, as I was making it far more complex than it needed to be! :?
Thanks for that Edward
Houdini Indie and Apprentice » Moving particles along a path?
- stevecullum
- 112 posts
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I had a play with your fixed scene and its pretty much what I need. However i need to modify the expression so that every new particle is born from position 0 and then travel up the spline. So think I would need an expression that says:
“If the particle age is 0 then its position on the U is 0 otherwise its position is equal to the frame no/total frames”
I'm still learning the expression functions, so I'm a bit lost on how to write this in the channel box.
Do you think my approach will create the desired effect?
“If the particle age is 0 then its position on the U is 0 otherwise its position is equal to the frame no/total frames”
I'm still learning the expression functions, so I'm a bit lost on how to write this in the channel box.
Do you think my approach will create the desired effect?
Houdini Indie and Apprentice » Moving particles along a path?
- stevecullum
- 112 posts
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Thanks Edward!
Yep I did misunderstand. ops:
Thanks for the file - I'll be able to try it later on
Yep I did misunderstand. ops:
Thanks for the file - I'll be able to try it later on
Houdini Indie and Apprentice » Always a fee for HD updates?
- stevecullum
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$237 for a license to use and learn the most powerful 3D app on the planet is a total bargain IMHO. Get your skills up and sooner or later it will pay off with the offer of some work. You can create assets in HD and convert them to licensed versions when that job does come in. Whats really good, is that you can rent a full license on a monthly basis, so as long as your job covers the cost (and it should if your needing Houdini to get involved!) then it pays for itself. One good dynamics shot for broadcast should easily cover the cost of the full annual license and then all you need to find is the annual maintenance fee.
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