shaderFX: lit sphere shader?

rooster

Hi, I'm wondering if anyone could give me some pointers creating a sphere map shader in shaderfx. There's one in the examples but I can't seem to get it to display correctly (it says set the vector space to world, but it appears that's the default anyway. it just looks like a smudge of colour)

any tips?
cheers!
-rich

Xoliul

Convert surface normal to screen-space (you always want the sphere map to be mapped in screen-space).
Use this normal as UV coordinate to sample from texture. The ss. normal will probably be in -1 to 1 range, while UV's are in 0-1 range. Plus, the normals need to start sampling from the center of the texture.
So, divide surface normals by 2 to scale them into a range of 1, then add 0.5 to them to translate them to the center.
Then just use only the X and Y components as UV's coordinates to sample.

Should be all there is to it save for some details.

arrangemonk

http://dl.dropbox.com/u/1484680/spheremap.SFX

did a spheremap node once

should do the job

shaderfx cant convert from tangent to view space

first you have to convert to modelspace then to viewspace
then add 1 and divide by 2

rooster

thanks arrangemonk, however when I try load the file I get the message 'file did not load correctly due to missing node(s): SphereMapping

do I need another file to go with it?
cheers!

Ace-Angel

I think they changed the node:

http://knol.google.com/k/shader-fx-environment-mapping#

rooster

I dunno ace I had a look on their forums and posts from 2006 suggest they've never had sphere mapping apart from the example file (which uses custom code rather than a node I think?). btw, does that example file work? am I just using it wrong somehow?

Ace-Angel

I checked it, and no dice. So I suppose you used a custom code ArrangeMonk? When I delete the last 3 lines of SphereMapping code, it loads, but I only get a Standard with a Texture.

arrangemonk

sorry, i fogot to give you the actual node
http://dl.dropbox.com/u/1484680/GRP_SphereMapping.ms
http://dl.dropbox.com/u/1484680/GRP_SphereMapping.sfx

copy both files to
3ds Max root\Scripts\ShaderFX\Nodes
and it should work

Ace-Angel

Awesome sauce man!

rooster

spot on arrangemonk, nice one cheers

Ben Cloward

Thanks for sharing this, arrangemonk. With your permission I'd like to alter it so that it supports an incoming normal socket (instead of using the normal from the surface vector node) so that it can be used with normal maps. I'd like to include the altered version in our next update of ShaderFX. Is that OK with you?

arrangemonk

do as you wish,

nothing to object to XD

rollin

I'm using a custom code node currently. A build in node is nice!

arrangemonk

sorry for necroposting but when are you planning to release the verson including the spheremap node?

Ace-Angel

I think they already included it in the latest version? Although it kinda buggy, so your mileage may vary.