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Technical Discussion » Curl Noise VOP implementation?
- chopstix
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Technical Discussion » Curl Noise VOP implementation?
- chopstix
- 27 posts
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Here's an example file I setup that illustrates the problem. You'll notice the noise is being affected by the collision object without forming the desired curls. I've tried to make the file as clear and as simple as possible and I'm pretty certain I am going about this the wrong way, so feel free to tear it apart
Any input would be very much appreciated
Any input would be very much appreciated
Technical Discussion » Curl Noise VOP implementation?
- chopstix
- 27 posts
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Does anybody have an example that shows how to properly setup the curl noise vop so that it creates the kind of curly “vorticies” it's supposed to once the particles its affecting come into contact with collision geometry?
I want to get it working in pops but I'm having trouble getting it to work with collision geometry. The vop says it needs distance to the collision object as well as the object normals, but I can't figure out how to get that data into the vop without first having to transfer the att's in pops. I'm getting the distance att through a collision pop but I'm not even sure if that's the right way to go about it.
Regardless, my results haven't given me the curly noise I'm looking for so I'm wondering if I'm missing a key component.
I want to get it working in pops but I'm having trouble getting it to work with collision geometry. The vop says it needs distance to the collision object as well as the object normals, but I can't figure out how to get that data into the vop without first having to transfer the att's in pops. I'm getting the distance att through a collision pop but I'm not even sure if that's the right way to go about it.
Regardless, my results haven't given me the curly noise I'm looking for so I'm wondering if I'm missing a key component.
Technical Discussion » Sound Driven Animation - Create Colors/Lights
- chopstix
- 27 posts
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Use the chop() or chopf() function to grab your channel data in your lighting parameters.
Technical Discussion » Per Light Shader Example (SOS!)
- chopstix
- 27 posts
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As it turns out, per light illuminance loops can work in 9.5 if setup correctly.
My setup was missing one key component: a front facing normal attribute
I've attached the fixed version I received today from SideFX.
My setup was missing one key component: a front facing normal attribute
I've attached the fixed version I received today from SideFX.
Technical Discussion » Ship Kelvin Wake
- chopstix
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No problem.
Another thing to note in my example setup is I hard coded the initial velocity so it only works on the X axis.
You can improve the setup by using the ship hulls normals as velocity (just put $NX,$NY,$NZ into velocity in a point sop after you've transfered the N att to the emission curves) This way the wake motion will continue to spread out behind the boat regardless of which direction it is traveling.
Another thing to note in my example setup is I hard coded the initial velocity so it only works on the X axis.
You can improve the setup by using the ship hulls normals as velocity (just put $NX,$NY,$NZ into velocity in a point sop after you've transfered the N att to the emission curves) This way the wake motion will continue to spread out behind the boat regardless of which direction it is traveling.
Technical Discussion » to write VOP network out to disk
- chopstix
- 27 posts
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Technical Discussion » Ship Kelvin Wake
- chopstix
- 27 posts
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One way to do it would be using a simple particle simulation.
I've attached a hip file that shows this method and uses the particles to displace the ocean surface geometry.
You could also use a greyscale render of the particles as a displacement shader.
I've attached a hip file that shows this method and uses the particles to displace the ocean surface geometry.
You could also use a greyscale render of the particles as a displacement shader.
Technical Discussion » Per Light Shader Example (SOS!)
- chopstix
- 27 posts
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**************
It should also be noted that the additional image planes only seem to show up when rendering directly from the rop, which can be found here:
**************
/obj/renderOutputs/test_render
It should also be noted that the additional image planes only seem to show up when rendering directly from the rop, which can be found here:
**************
/obj/renderOutputs/test_render
Technical Discussion » Per Light Shader Example (SOS!)
- chopstix
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After looking at this some more I realize my textures are rendering with transparency, but only after the rays have contacted the surface and returned a color.
The rays hit the surface and if it's 0 they return 0, if it's 1 they return 1.
What they don't do is continue through the surface to the other side when the value is 0 or anything less than 1. How do I tell the rays to continue through the transparent areas and continue to return color information from the other side?
This is something which happens naturally when you use the built in lighting model vop, but since I'm building my diffuse from scratch I am obviously missing an important step.
As I said in my initial post, I'm new to shader building so I am probably missing some fundamental understanding here.
Any help or pointers to get me on track would be greatly appreciated
The rays hit the surface and if it's 0 they return 0, if it's 1 they return 1.
What they don't do is continue through the surface to the other side when the value is 0 or anything less than 1. How do I tell the rays to continue through the transparent areas and continue to return color information from the other side?
This is something which happens naturally when you use the built in lighting model vop, but since I'm building my diffuse from scratch I am obviously missing an important step.
As I said in my initial post, I'm new to shader building so I am probably missing some fundamental understanding here.
Any help or pointers to get me on track would be greatly appreciated
Technical Discussion » Displacement using node from surface shader
- chopstix
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Technical Discussion » Per Light Shader Example (SOS!)
- chopstix
- 27 posts
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FYI, the reason my lights are currently set to red, green, and blue is for testing purposes only.
The real render will have a beauty diffuse pass in “C”, and specular under “spec.”
Lights are colored so I can see their actual effect and compare them to the results I'm getting from my individual light layers.
The real render will have a beauty diffuse pass in “C”, and specular under “spec.”
Lights are colored so I can see their actual effect and compare them to the results I'm getting from my individual light layers.
Technical Discussion » Per Light Shader Example (SOS!)
- chopstix
- 27 posts
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Hey guys I have attached an example file which shows the issue I'm having.
This is my first shader so *please* go easy on me It's definitely not perfect.
Here's what I'm looking for: A shader that has a nice looking diffuse pass and spec pass, as well as individual per light passes for 3 lights or so. The shader needs to use a texture with transparency, much like a VEX_decal shader or a VEX_layered_surface_shader.
The problem I'm having is my diffuse and spec passes work fine, but the individual lighting passes don't seem to be taking my transparencies into account.
To see what I'm talking about:
1.) open up the attached file and render the “test_render” rop.
2.) check out the extra image planes. You'll see that C works, spec works, zdepth works, and perlight_diff_keyLight_MAIN, fillLight_MAIN, and rimLight_MAIN *appear* to work.
3.) look a little closer and compare the “C” pass with one of the individual lighting passes. You'll notice the individual lighting passes treat the spheres as if there is no transparency.
You'll find the vop network creating the image here:
/obj/exampleVOP/decal_deepraster/
And the per light illumination loop is here:
/obj/exampleVOP/decal_deepraster/illumination_loop_diffuse
(If you're curious, the output rop sources an expression I got from odforce which can be found under >edit>aliases_and_variables on the “expressions” tab. )
Any idea why I'm not getting transparencies in my individual lighting passes?
Thanks in advance!
This is my first shader so *please* go easy on me It's definitely not perfect.
Here's what I'm looking for: A shader that has a nice looking diffuse pass and spec pass, as well as individual per light passes for 3 lights or so. The shader needs to use a texture with transparency, much like a VEX_decal shader or a VEX_layered_surface_shader.
The problem I'm having is my diffuse and spec passes work fine, but the individual lighting passes don't seem to be taking my transparencies into account.
To see what I'm talking about:
1.) open up the attached file and render the “test_render” rop.
2.) check out the extra image planes. You'll see that C works, spec works, zdepth works, and perlight_diff_keyLight_MAIN, fillLight_MAIN, and rimLight_MAIN *appear* to work.
3.) look a little closer and compare the “C” pass with one of the individual lighting passes. You'll notice the individual lighting passes treat the spheres as if there is no transparency.
You'll find the vop network creating the image here:
/obj/exampleVOP/decal_deepraster/
And the per light illumination loop is here:
/obj/exampleVOP/decal_deepraster/illumination_loop_diffuse
(If you're curious, the output rop sources an expression I got from odforce which can be found under >edit>aliases_and_variables on the “expressions” tab. )
Any idea why I'm not getting transparencies in my individual lighting passes?
Thanks in advance!
Technical Discussion » WIP: Ocean and ship interaction
- chopstix
- 27 posts
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Technical Discussion » Scattering points onto geometry with normals
- chopstix
- 27 posts
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Ah, I didn't realize that's what you were asking. I thought you already had your normals from your primitives on the points and wanted to know how to transfer those normals to your sub geometry in a copy. Glad you got the answer you were looking for.
Technical Discussion » how to add bump to vex layerd ?
- chopstix
- 27 posts
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I just go with what works, I wasn't able to get this to work in a material sop.
I personally prefer the shader sop for 2 major reasons
1.) it works
2.) it has tabs named “displacement,” “surface,” etc to keep your material assignments organized.
Good luck
I personally prefer the shader sop for 2 major reasons
1.) it works
2.) it has tabs named “displacement,” “surface,” etc to keep your material assignments organized.
Good luck
Technical Discussion » how to add bump to vex layerd ?
- chopstix
- 27 posts
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I don't think you can add a bump from inside the vex layered surface shader.
You'll need to put down a VEX_Displace_Map shop and put your image map in there.
At the sop level, use a shader sop. Source your layered_surface shop on the surface tab and your displacement shop on the displacement tab.
You'll need to put down a VEX_Displace_Map shop and put your image map in there.
At the sop level, use a shader sop. Source your layered_surface shop on the surface tab and your displacement shop on the displacement tab.
Technical Discussion » Scattering points onto geometry with normals
- chopstix
- 27 posts
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Here's an example file that I think should answer your question.
a few things to note:
-the node “do_scatter_pre_copy” is a switch node. Set it to “1” to do the scatter before the copy, “0” to do the scatter after the copy.
-in the copy node called
“normals_overriden_by_template_normals_on_attribute_tab” you'll see the normals have been copied over from the template normals and are overriding the normals from the “sub geometry” Note how you can set normals, multiply normals, add normals, and subtract normals. In this case the normals are being set using the template geometry and applied to the “sub geometry” points.
a few things to note:
-the node “do_scatter_pre_copy” is a switch node. Set it to “1” to do the scatter before the copy, “0” to do the scatter after the copy.
-in the copy node called
“normals_overriden_by_template_normals_on_attribute_tab” you'll see the normals have been copied over from the template normals and are overriding the normals from the “sub geometry” Note how you can set normals, multiply normals, add normals, and subtract normals. In this case the normals are being set using the template geometry and applied to the “sub geometry” points.
Technical Discussion » Illuminance loop loopiness (VOPs)
- chopstix
- 27 posts
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Well I'm asking around quite a bit outside the forums and from what I can gather this is not possible in current builds of Houdini.
I'll post this as a suggestion for future releases as it would be a great feature.
I'll post this as a suggestion for future releases as it would be a great feature.
Technical Discussion » Illuminance loop loopiness (VOPs)
- chopstix
- 27 posts
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