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Technical Discussion » heightfield display resolution
- Serg
- 511 posts
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How do I display heightfields at their actual resolution instead of what appears to be a 20x20 grid with a normal map on top?
Solaris and Karma » Husk Procedural hair example
- Serg
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I tried and failed miserably to reverse engineer my own graph bgeo for guide deform...
BUT, just as I was beginning to lose the will to live, I had the idea to edit/hack graph.bgeo that comes with the hair proc hda. In my case set the "flag_bypass" attribute on the corresponding point of "move_to_skin_pos2". Which of course worked fine. Phew...
Anyway, just noting here that that lifeline exits for these unusual fixes or overriding other parms without the pain involved to make it all work properly.
BUT, just as I was beginning to lose the will to live, I had the idea to edit/hack graph.bgeo that comes with the hair proc hda. In my case set the "flag_bypass" attribute on the corresponding point of "move_to_skin_pos2". Which of course worked fine. Phew...
Anyway, just noting here that that lifeline exits for these unusual fixes or overriding other parms without the pain involved to make it all work properly.
Solaris and Karma » Husk Procedural hair example
- Serg
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Also, I'm thinking if one really needs to bother with parameter promotion at all?
Why not create a generic hda that has only parameter for file path to the graph.bgeos and save button? Inside would be an editable subnet. So instead of changing parms at lop level we change them in the subnet and publish changes to the bgeo with the save button?
Why not create a generic hda that has only parameter for file path to the graph.bgeos and save button? Inside would be an editable subnet. So instead of changing parms at lop level we change them in the subnet and publish changes to the bgeo with the save button?
Solaris and Karma » Husk Procedural hair example
- Serg
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I'm beginning to grok what's what & where with the hair procedural thanks to elovikov's helpful explanation, but in order to rewrite the currently embedded "hair_graph.bgeo.sc" with the fix, I need the hip file from hence it came (sadly the sopnet is not included in the hair proc hda).
Would it be possible to share it here please? This would also probably make it a lot easier to add more parameters as we see fit?
Cheers
S
Would it be possible to share it here please? This would also probably make it a lot easier to add more parameters as we see fit?
Cheers
S
Solaris and Karma » Husk Procedural hair example
- Serg
- 511 posts
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Hi there,
I am attaching dirt/snow (in the form of curled up curves) to fur using the hair_procedural. It has to be done with the hair procedural because the caches are prohibitive.
Unfortunately this does not work, seemingly only because guidedeform is forcing the root points to project to the skin (not sure if that is truly necessary in any case) as you can see.
Now I thought I would simply make a new version of guidedeform with the move_to_skin_pos wrangle bypassed as shown, and then simply change the reference in the procedural code to the new one, and thusly avoid having to endure the headache of making a new procedural... but I cannot find where that is. Any ideas?
Alternatively adding "Geometry to Deform" so that I could set "Arbitrary Geometry" as well as the "Rigidly Transform Pieces" toggle parameters would resolve the problem.
Cheers
S
I am attaching dirt/snow (in the form of curled up curves) to fur using the hair_procedural. It has to be done with the hair procedural because the caches are prohibitive.
Unfortunately this does not work, seemingly only because guidedeform is forcing the root points to project to the skin (not sure if that is truly necessary in any case) as you can see.
Now I thought I would simply make a new version of guidedeform with the move_to_skin_pos wrangle bypassed as shown, and then simply change the reference in the procedural code to the new one, and thusly avoid having to endure the headache of making a new procedural... but I cannot find where that is. Any ideas?
Alternatively adding "Geometry to Deform" so that I could set "Arbitrary Geometry" as well as the "Rigidly Transform Pieces" toggle parameters would resolve the problem.
Cheers
S
Solaris and Karma » Mulitple uv sets in Solaris
- Serg
- 511 posts
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Hi there, any news on this? It appears to be as broken now as it ever was.
Currently facing terabytes of converting stuff...
Currently facing terabytes of converting stuff...
Solaris and Karma » Texture Map on Karma Hair Shader
- Serg
- 511 posts
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Thanks Brian,
Is that a primitive or point uv attribute?
We use custom hair tools, so I am manually doing the Solaris compatibility layer. That is I fetch the uv from the skin with a raysop or xyzdist to the root points, then promote them to primitive, and tried to convert back expand to the points. It all works fine if I colour the points in SOPs which is what I resorted to doing.
Also, I'm not using a kma_Hair shader, it's good ol Vops.
I will set up a sample scene when I get half a chance.
Cheers!
S
Is that a primitive or point uv attribute?
We use custom hair tools, so I am manually doing the Solaris compatibility layer. That is I fetch the uv from the skin with a raysop or xyzdist to the root points, then promote them to primitive, and tried to convert back expand to the points. It all works fine if I colour the points in SOPs which is what I resorted to doing.
Also, I'm not using a kma_Hair shader, it's good ol Vops.
I will set up a sample scene when I get half a chance.
Cheers!
S
Solaris and Karma » Texture Map on Karma Hair Shader
- Serg
- 511 posts
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Hi there,
What does one have to do to get Karma to render texture maps on hair? As in when UV's transferred from skin, aka the most common/basic use.
I have tried "uv" attribute on prims or points, different names in case the treacherous renaming might be happening behind my back, etc... nothing works to apply a texture on my furry creature other than baking Cd attribute.
Is this how it's supposed to be?
Thanks
S
What does one have to do to get Karma to render texture maps on hair? As in when UV's transferred from skin, aka the most common/basic use.
I have tried "uv" attribute on prims or points, different names in case the treacherous renaming might be happening behind my back, etc... nothing works to apply a texture on my furry creature other than baking Cd attribute.
Is this how it's supposed to be?
Thanks
S
Solaris and Karma » How do I render a nurbs curve
- Serg
- 511 posts
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Do I have to export particular attributes or file formats from sops in order to render smooth curves?
Is it possible to render alembic nurbs curves as smooth curves even if not exactly alike?
I cannot resample them to render as linear curves because this would result in far too much data.
Attemps to change NurbsCurves to BasisCurves via geometry settings lops or the basiscurves lop (if that is what is for... it just disappears the geometry) fail.
Cheers
S
Is it possible to render alembic nurbs curves as smooth curves even if not exactly alike?
I cannot resample them to render as linear curves because this would result in far too much data.
Attemps to change NurbsCurves to BasisCurves via geometry settings lops or the basiscurves lop (if that is what is for... it just disappears the geometry) fail.
Cheers
S
Houdini Lounge » Can I map acceleration to a shader?
- Serg
- 511 posts
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In Vop's create a “Parameter” vop, set the type and name to be the same same as the geometry attribute.
cheers
S
cheers
S
Houdini Lounge » light refl vs geo refl
- Serg
- 511 posts
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Option Off is not really any more physically correct than Option On… You can get identical renders with either option (apart from the bug with reflections) just by changing Intensity till they match in output.
It's just a question of convenience and what you want the Intensity parameter to mean.
Whether someone likes it On or Off is actually irrelevant, what matters is that the Light be reflected correctly regardless.
cheers
S
It's just a question of convenience and what you want the Intensity parameter to mean.
Whether someone likes it On or Off is actually irrelevant, what matters is that the Light be reflected correctly regardless.
cheers
S
Houdini Lounge » light refl vs geo refl
- Serg
- 511 posts
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hmmm, this should be fixed so that turning Off “Normalize Light Intensity to Area” isn't a pre-requisite for expected reflections.
I don't like this option, turning it Off only adds to physical correctness in that the output Intensity will change correctly with respect to the size of the light, if you were to think of intensity as some amount of light to be spread over an area… but this is much less intuitive than simply thinking of the value as the expected outcome. The only situation I can think off where this would be useful is if you were animating area size and wanted to actually observe this effect.
It's kind of an option you would turn off if you want to mimic a real world inconvenience! After all, wouldn't a Gaffer love to be able to turn this ON?
S
I don't like this option, turning it Off only adds to physical correctness in that the output Intensity will change correctly with respect to the size of the light, if you were to think of intensity as some amount of light to be spread over an area… but this is much less intuitive than simply thinking of the value as the expected outcome. The only situation I can think off where this would be useful is if you were animating area size and wanted to actually observe this effect.
It's kind of an option you would turn off if you want to mimic a real world inconvenience! After all, wouldn't a Gaffer love to be able to turn this ON?
S
Houdini Lounge » light refl vs geo refl
- Serg
- 511 posts
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And the workaround I suggested above wont work fully unless “Render Light Geometry” of the Specular light (with attenuation Off) is switched Off… leave the Diffuse only lights “Render Light Geometry” to On.
For some reason turning attenuation Off causes the intensity of the light geometry as seen directly by the camera to sky rocket to about 123, whereas the intensity of the light as seen on the reflective surface seems correct'ish.
This is all very confusing and unpredictable.
Correct me if I'm wrong, but, if I set a light intensity to 0.5, I expect to see:
- The Intensity of the light geometry as seen directly by the camera to be 0.5, regardless of attenuation settings.
- The intensity of the light geometry as seen in a 100% perfect mirror reflection to be 0.5.
- The intensity of the a lambertian reflection to be 0.5 at Zero distance from the light and thereafter modified by whatever attenuation function.
cheers
S
For some reason turning attenuation Off causes the intensity of the light geometry as seen directly by the camera to sky rocket to about 123, whereas the intensity of the light as seen on the reflective surface seems correct'ish.
This is all very confusing and unpredictable.
Correct me if I'm wrong, but, if I set a light intensity to 0.5, I expect to see:
- The Intensity of the light geometry as seen directly by the camera to be 0.5, regardless of attenuation settings.
- The intensity of the light geometry as seen in a 100% perfect mirror reflection to be 0.5.
- The intensity of the a lambertian reflection to be 0.5 at Zero distance from the light and thereafter modified by whatever attenuation function.
cheers
S
Houdini Lounge » light refl vs geo refl
- Serg
- 511 posts
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Yeah, the specular reflection is multiplied by the attenuation… it really shouldn't.
The workaround is to have twin light set-ups, one has “Affect Diffuse” On and “Affect Specular” Off, the other the reverse setting and with attenuation Off.
afaik, in the real world the intensity of a specular reflection (edit: arriving at a perfectly reflective surface) can only be affected by an opaque intermediary medium, like fog or tinted glass, or a surface roughness that causes the reflection to be spread over a bigger area.
Another gripe I have with “physical” “specular” light reflections is how they are shadowed by occlusions along “L” (regular diffuse shadows) rather than occlusions along the reflection vector.
S
The workaround is to have twin light set-ups, one has “Affect Diffuse” On and “Affect Specular” Off, the other the reverse setting and with attenuation Off.
afaik, in the real world the intensity of a specular reflection (edit: arriving at a perfectly reflective surface) can only be affected by an opaque intermediary medium, like fog or tinted glass, or a surface roughness that causes the reflection to be spread over a bigger area.
Another gripe I have with “physical” “specular” light reflections is how they are shadowed by occlusions along “L” (regular diffuse shadows) rather than occlusions along the reflection vector.
S
Technical Discussion » Massive viewport lag [SOLVED]
- Serg
- 511 posts
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twod
There's currently a bug logged with similar symptoms, but with a Quadro 1700. I haven't been able to reproduce it on a Quadro 3800, though. Could you check if there are any warnings/errors in the Display Options info button (lower-right corner info/warning/error icon)?
In the meantime, you can probably turn off material shaders in the Effects tab to restore interactivity.
ah beat me to it.
didnt know about turning off material shaders. though will try it when I get back to that machine. I assumed switching to a low tech mode like wireframe or solid would bypass all that (it doesnt).
S
Technical Discussion » Massive viewport lag [SOLVED]
- Serg
- 511 posts
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Simon
I'm seeing a massive delay in the viewport catching up with my mouse movements. So when I zoom, pan or tumble about 3 seconds later the model stops zooming, panning and tumbling. I've tried turning off materials which helps for simple models but for ones with high poly counts it's just no good.
With materials on it's more like a 10 second delay.
Nvidia Quadro FX 570
Driver - 6.14.11.6926 and also tried 6.14.12.5912
Win XP 64
Any ideas how to switch it back to H10 speedy mode?
Sounds similar to a bug I'm experiencing (reported to support)
I do wish I could flip a switch and use good old but reliable H10 GL…
> It seems the Gold release and up are buggered on my system from a Gl
> pov. Viewport display is extremely sluggish when more than one
> geometry is displayed, sometimes this manifests as a massive lag, when
> you drag the mouse to move the view it hangs then plays back your
> mouse movements a few seconds later.
> The sluggishness seems to momentarily spill outside Houdini to mundane
> apps.
>
> Doing a few things seem to exchange functionality for normal
> interactivity levels:
> - Turning off Display flag of all but one object.
> - Assigning a different type of shader, such as a “Material Shader
> Builder”. Which leads me to guess its some sort of GL shader compiler
> issue which only manifests when the same shader is applied to multiple
> objects.
>
> Tried updating to latest drivers to no avail.
>
> My system is:
>
> Windows XP 64bit
> Quadro FX1700, Driver Version 259.12.
> Running Dual Monitors in “Dual View” mode.
>
> Thanks
>
> Sergio
>
Technical Discussion » Mantra VS Mantra VS Etc...
- Serg
- 511 posts
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Naturally people reading this might wonder why don't I just write the cache with the Irradiance Cache stuff that's already there in the rop. After all it already does a lot of the stuff I need, it already knows to place samples in important places like corners and with Poisson disc distribution (from looking at cloud).
Unfortunately my attempts to use it didn't work out… technical reasons for not using rop irr cache are (some of these are bugs), and rfe's for my ideal caching system:
- It is totally buggered when used with the Irradiance function, there are impossible to solve large black unpainted areas everywhere.
- The point cloud saved to disk seems incomplete/corrupted relative to what you can see sampled on screen. This means I cant use the cloud in a simple pcloud shader. Maybe this related to the above.
- Oddly it seems to work properly with “occlusion”, though the saved cloud is still corrupted.
- I need a cache which I can direct to the Gather loops for tracing against in secondary rays. To do this the cache system has to output from a Vop so that I can plug it into the parm that gets exported to the Gather loop.
- I need a cache that is not limited to specific functions or one time use only. i.e. currently it only works with occlusion or irradiance but not both at the same time, else you get garbage out… You cant for example use irradiance for irradiance AND use another irradiance do cached reflections trick, coz they step on each others toes.
I want to add as many caches per shader as I want and read them wherever I want. Basically I would like this to be as easy as the AOV system:
- plug the stuff you want to cache into a cache vop and set name.
- go to rop and use multiparm (like the aov system) and match the names.
- each instance in the multiparm is basically a independent full featured cache ui, here you choose whether it's view dependant, interpolation/error option, whatever.
- back in the vopnet plug import cache vop to whatever you want. Done.
Or maybe the better answer is to make the pcwrite/generate/read more full featured so that they can generate irr cache like point distributions (maybe already possible and I just don't know how) and pcread to have more sophisticated interpolation methods? or both methods… The former method being enough for 99% cases and easy to understand since its analogous to AOV's, and the more obscure stuff for when job calls for extra clever coolness some sort…
cheers
S
Unfortunately my attempts to use it didn't work out… technical reasons for not using rop irr cache are (some of these are bugs), and rfe's for my ideal caching system:
- It is totally buggered when used with the Irradiance function, there are impossible to solve large black unpainted areas everywhere.
- The point cloud saved to disk seems incomplete/corrupted relative to what you can see sampled on screen. This means I cant use the cloud in a simple pcloud shader. Maybe this related to the above.
- Oddly it seems to work properly with “occlusion”, though the saved cloud is still corrupted.
- I need a cache which I can direct to the Gather loops for tracing against in secondary rays. To do this the cache system has to output from a Vop so that I can plug it into the parm that gets exported to the Gather loop.
- I need a cache that is not limited to specific functions or one time use only. i.e. currently it only works with occlusion or irradiance but not both at the same time, else you get garbage out… You cant for example use irradiance for irradiance AND use another irradiance do cached reflections trick, coz they step on each others toes.
I want to add as many caches per shader as I want and read them wherever I want. Basically I would like this to be as easy as the AOV system:
- plug the stuff you want to cache into a cache vop and set name.
- go to rop and use multiparm (like the aov system) and match the names.
- each instance in the multiparm is basically a independent full featured cache ui, here you choose whether it's view dependant, interpolation/error option, whatever.
- back in the vopnet plug import cache vop to whatever you want. Done.
Or maybe the better answer is to make the pcwrite/generate/read more full featured so that they can generate irr cache like point distributions (maybe already possible and I just don't know how) and pcread to have more sophisticated interpolation methods? or both methods… The former method being enough for 99% cases and easy to understand since its analogous to AOV's, and the more obscure stuff for when job calls for extra clever coolness some sort…
cheers
S
Technical Discussion » Mantra VS Mantra VS Etc...
- Serg
- 511 posts
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btw these images were all saved with a 3.0 gamma or they would be just too dark to really show what's up.
Technical Discussion » Mantra VS Mantra VS Etc...
- Serg
- 511 posts
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Hi,
Here's the PBR scene.
I may get round to setting up other “standard” scenes like Sponza n all that. Very useful for use as direct comparison to other renderers.
cheers
S
Here's the PBR scene.
I may get round to setting up other “standard” scenes like Sponza n all that. Very useful for use as direct comparison to other renderers.
cheers
S
Technical Discussion » Mantra VS Mantra VS Etc...
- Serg
- 511 posts
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andrewc
Just a note that photon maps were never intended to be rendered directly. Your image rendered with PBR and indirect photons (which looks pretty good) is the intended workflow. Directly visualizing photon maps is available mainly for debugging.
Perhaps the parameter should be named “Visualize Photons” or something. It sure makes you wish there was a good enough approximation to render diffuse bounces extremely quickly
andrewc
Also, the photon distance threshold is not an absolute distance but is relative to the distance between photons - which appears to be smaller than the opening in your scene based on the photon render.
Some of the photons around the entrance to the cavity in the top right really looked that big. When I looked at the cloud in sops it was extremely dense near the light, elsewhere it was very sparse.
andrewc
I think you're custom solution appears to be another method to generate photons that is view-dependent?
I generated the cloud from a camera looking down on the entire scene isometrically… to avoid not having enough samples at grazing angles, but they aren't photons (you made me look up how they fundamentally work in the beta forum) , I'm just running my regular diffuse bounces shader with 512 samples and pcwritting the stuff at a low 256x256 resolution.
Btw, I would love to be able to setup pre-rendering processes in the same way we can calculate the photon map without rendering a whole separate ifd and render sequence.
For diffuse bounces this seems much better than photons because the resolution is relatively uniform, and you can just do “sampling” as opposed to shooting an enormous amount of photons (generation time and storage become significant not to mention massively wasteful), because of this you don't have to use Distance Threshold. Its just a lot easier to deal with… you can always just turn up the samples or sample resolution, whereas the photon method could prove impossible to deal with when given a very adverse situation, and sod's law says that is precisely what will happen the first time you use it for real.
In a shot where the camera walks through a large scene and there is animated stuff it may be better to bake with a polar projection camera parented to the shot camera…. The drop in samples at very grazing angles may turn out to be problematic though. It really needs the super brains such as yourself to implement irradiance cache, as opposed to me doing yet another hack.
A as simple as possible irradiance cache (one that renders as simple as a pcloud shader) would be very useful right now because it would be limited to being visible to indirect rays, the fancy stuff can wait… like how modo/vray do their fancy sample interpolation schemes to be able to render the stuff directly super quick.
I think the biggest thing to take away from this is, by far, the massively dramatic impact of using the irradiance cache to trace glossy reflections against! This is more than huge enough for me to stick to my current Gather technique and skip PBR altogether for another good while!
Cheers
Serg
PS. OT
Btw I noticed the pcwritting stuff now writes a point every time a ray event happens (this is cool, even though I cant think of anything to use it for right now)… but took me ages to realise I had to block the writing if ray bounce level > 0 or else I would quickly accumulate 100s of millions of the stuff. There should a section on the help somewhere where we can view changes to existing functions as well as new stuff… i.e. the tangent space function now has a load more arguments than before so my normal map shaders are now broken. Have a look at the “What's New” section and compare that to what's actually happened.
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