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chang

Casting shadow on i3d

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Hi,

It seems i3d-generated clouds are not casting a shadow on the ground.

Am I missing something ? Or is it impossible ?

Thanks in advance :)

post-21-1051002399.jpg

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I think its imposible with 3D Texture Fog "atmosphere" shader

because atmosphere shader is carried out

after surface shader has finished.

Try 3D Texture Cloud "surface" shader.

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If i3d texture was not generated from metaballs,

than the size of 3d texture would usually be a little bit larger

than the size of the object it was made off.

That is why you can loose details if you assign

this shader to the object directly.

If it has happened you could use the following scheme:

"Source of i3d" SOP -> Box SOP -> XForm SOP (scale a litle bit) -> Shader SOP

post-136-1122473193_thumb.jpg

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Wow, thanks again ! Andrew. :lol:

--

(Above is fog. Below is surfaceShaded. With same option)

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Hi Chang

Really cool looking clouds, i didn't quite understand

AndrewVK explaination of how to get the clouds casting shadows

"Source of i3d" SOP -> Box SOP -> XForm SOP (scale a litle bit) -> Shader SOP

a hipc file of the cloud torus would be very helpful, i am trying the same type of effect and can never get my clouds to cast shadows either.

Later

Ben

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..It's strange uploading is not allowed by the maximum-file-size..

My file is just 83k, the maximum is 153k. :blink:

Thrasher, give me your email address, I'll send it to you.

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Still there are some limitations...

The standard 3D Texture Cloud "surface" shader works incorrectly

in case if "Object Inside Cloud" (because of Z-Sorting).

3D Texture Fog "atmosphere" shader does not have this limitation,

but it cannot cast shadows. :(

IMHO:

I think it is possible to rewrite the shader

to handle "Object inside" and/or/both "Camera inside" situations,

though it would work slower.

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I think its imposible with 3D Texture Fog "atmosphere" shader

because atmosphere shader is carried out

after surface shader has finished.

Try 3D Texture Cloud "surface" shader.

5871[/snapback]

Hello,

How did you do the cloud with surface shader. To what must you connect the surface shader if there is no Atmosphere node. I don't get my shadows like in the example picture.

Any help is welcome.

thx

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Here an example  :)

Houdini 8.313

20056[/snapback]

Thanks AndrewVK for the scene file. Now I understand the set-up.

I must say this Houdini forum is top-notch, with helpfull and friendly people. Maya users , eat your heart out. Houdini rocks!

Thanks, thanks , thanks...

bernard

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Thanks AndrewVK for the scene file. Now I understand the set-up.

I must say this Houdini forum is top-notch, with helpfull and friendly people. Maya users , eat your heart out. Houdini rocks!

Thanks, thanks , thanks...

bernard

20057[/snapback]

Hello,

How can I cast shadows ON the cloud (example: like cloud behind a wall -see pictures from chang)

thx,

bernard

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Just turn "Object Shadowing" parameter ON (VEX 3D texture Cloud shader)

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Just turn "Object Shadowing" parameter ON (VEX 3D texture Cloud shader)

20068[/snapback]

Thanks AndrewVK.

bernard

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Hey Andrew? or anyone out there? Do you guys have any examples of creating volumentrics using pointcloud?

It's still mystery for me and would like to learn something about it.

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I have no such an experience..but i am 100% sure...PCloud will work just fine

without I3D at all. Better or no...i dont know...but faster :)

Especially after new functions for work with metaballs have appeared.

metamarch...metaimport...metaweight etc.

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Any examples at all? I have not touched poin clouds at all. I know there is some technique to use poin clouds replacing i3d completly, but I can't find any informations about it. I don't even know where to start.

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