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Marc

Hair revisited

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Jason has convinced me to publish a VEX version of my hair shader.

15637[/snapback]

That's great news! Thanks in advance Arno :)

I already converted the surface shader function, but since I

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You can download Houdini Apprentice from here

http://sidefx.vislab.usyd.edu.au/

and get free everything! Renderer the works. Completely compatible with the full Houdini.

I'm slightly confused how you converted your functions to VEX without it though, so maybe this isn't what you mean. ;)

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You can download Houdini Apprentice from here

http://sidefx.vislab.usyd.edu.au/

and get free everything! Renderer the works. Completely compatible with the full Houdini.

I'm slightly confused how you converted your functions to VEX without it though, so maybe this isn't what you mean.  ;)

15647[/snapback]

Ha ha... :) The answer is pretty simple ! I did a renderman (sl) version and since both shading languages (VEX & sl) are almost identical, there was almost nothing to do ! :)

OK, I

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Hi Marc,

I was wondering if you could send me a hair geometry sample ?! (your hair ball) :) I wrote a VEX hair shader but have no geometry for testing...

Thanks

Cheers !

Arno

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I've read this whole thread and am a bit concerned that getting cartoony hair on my cartoon monkey is going to be a whole lot more complicated than I could possibly have imagined...

:blink:

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I've read this whole thread and am a bit concerned that getting cartoony hair on my cartoon monkey is going to be a whole lot more complicated than I could possibly have imagined... 

:blink:

15829[/snapback]

That depends on the number of hairs, the shading will not be the problem ! :)

Arno

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Hey Arno

I just got round to reading this now. Do you still need the hairball? I think I've got it somewhere..

Cheers

Marc

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Someone needs to make a quick OTL to calculate the maj_axis that Arno was talking about in the fur/fibre/hair thread still. I'd try it but I'm slammed right now.

Take care,

Jason

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Hey Arno

I just got round to reading this now. Do you still need the hairball? I think I've got it somewhere..

Cheers

Marc

15838[/snapback]

Of course I do :)

Can I download it via ftp ??

Thanks

Arno

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Someone needs to make a quick OTL to calculate the maj_axis that Arno was talking about in the fur/fibre/hair thread still.  I'd try it but I'm slammed right now.

Take care,

Jason

15840[/snapback]

Im not shure if I

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Here's the mandriball file.

It's got Mario's hair shader built in, along with the stuff for the hairball. I haven't tested it recently, so it could very well not work.

I too will add my name to the slammed list.

M

mandriball.tm.tar.gz

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some frames from the hairball: rendered with the latest version from spice, 5000 hairs, 2 lights.

post-77-1106291850_thumb.jpg

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some frames from the hairball: rendered with the latest version from spice, 5000 hairs, 2 lights.

15864[/snapback]

Thanks Mike,

just two questions:

1.) Where are the light sources ?

2.) Did you set the major_axis vector correctly ?

The result look a bit different from my proprietary renderer. Could you try version 1.1 please ?

Thanks a lot !!!

Arno

arno_hair_far_field_v1_1.zip

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You mean something like this?

(VEX Major Axis SOP generated from VOP net)

15863[/snapback]

Thanks a lot Edward,

the code looks right (But I dont know how to use it with Houdini) !:)

Of course the semi major axis is following the geometry now without variation. For realistic results one has to perturb a bit . Therefore I will add some code to this otl...

Cheers !

Arno

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Theoretically, one should be able to just append the SOP to the geometry, set it the render flag on it and render away.

However, I tried it with the shader and it didn't seem to work. Perhaps you didn't put the "export" keyword in the shader function declaration for the parameters which can be per point?

Since you want to modify it, I've included the .hip file that was used to create the .otl file.

major_axis.hipnc.gz

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However, I tried it with the shader and it didn't seem to work. Perhaps you didn't put the "export" keyword in the shader function declaration for the parameters which can be per point?

This shouldn't be necessary - the export keyword is only to tell Mantra to keep the information around for writing to Deep Raster layers. Any parameter in a shader can be overriden by geo attributes without any extra effort on the part of the shader-writer.

Perhaps I'll get a moment this weekend to play with this! :)

Take care,

Jason

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