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craigs
02-10-2005, 02:20 AM
I checked out a thread based on SSS, http://www.lamrug.org/resources/doc/sss-skin-tutorial.pdf

which talks about apply the Misss_Fast_Skin_Maya shader, I was wondering if anyone has had any luck with this, because all im getting is a blank render, I was wondering do you have to set anything specific in the render globals.
The most i've got out of it, is something of a line in the aplha channel.
Myabe someone would be kind enough to advise.
regards
craig

Jozvex
02-10-2005, 03:00 AM
Go for your life:

http://www.cgtalk.com/showthread.php?t=163360

That's a whole massive thread on it. A great shader!

:thumbsup:

WhiteRabbitObj
02-10-2005, 04:37 AM
And the most important piece of information in that entire lengthy thread for getting started is:


Ok! That's it! I can't take it any longer!

For all of you guys that still can't get it working, follow these steps:

1. Install the MR shaders/scripts/icons etc as instructed in the readme file.
2. You shouldn't need to edit that AE template script file that Phoenix mentioned because a modified one comes in the package and you already installed it with the other scripts.
3. Start Maya.
4. Create one/some objects.
5. Create a light and get the scene looking how you want it for the final render (with just the Lambert1 shader still applied).
6. Select the object you want the fast SSS shader applied to.
7. Right click on it in the viewport and go to Materials > Assign New Material > Misss_fast_simple_maya.

That's the shader I've been using so we'll just use that for now. It's good. If you do a render now, you'll just get a funny tan coloured shader. Leave all the settings the way they are. In fact, do a render now and 'keep' the image so you can compare later and see that everything works.

8. Open out the Lightmap section of the shader.
9. Click on the texture applying button next to the lightmap slot.

It will automatically create the 'mentalrayTexture' shader that you need and open it's properties.

10. On the mentalrayTexture attributes, tick the Writable checkbox.
11. Change the File Size Depth to 32 bits.

You MUST change it to 32 bits for it to work.

12. Change the lightmap resolution to double the width of your render resolution, and to the same height as your render resolution.

For example, if you're going to render at 640x480 your lightmap should be 1280x480.

13. In the Image Name slot, type "\mySuperSSS" or something like that (but without the quotes).

You do NOT give a file extension as Mental Ray uses whatever it's lightmap file format is (extensionless). You MUST start the name with either a \ (UNIX style) or with C:\ etc because that's just the way it goes, you can't just type in a filename with no path. Going on my example, "\mySuperSSS" will create a lightmap file with no extension at C:\mySuperSSS. But don't look for it yet (even if you render) because we aren't finished yet.

14. Navigate your way to the Shading Group node of the Misss_fast_simple_maya (so you can see all the MR shader slots).

15. Click on the texture-applying button next to the 'Light Map Shader' slot.

16. Apply a Misss_fast_lmap_maya shader. It will take you to the attributes of it.

Notice that there's a "Include indirect lighting" checkbox at the top, tick that later if you want to add Final Gather to the SSS effect.

17. Open out the Lightmap Write section.

18. Into the lightmap slot, type "mentalrayTexture1" and press enter.

It just connects this shader to the mentalrayTexture shader, so if the name of your mentalrayTexture shader is different just type that instead. Alternatively you could drag and drop the mentalrayTexture shader onto that slot to achieve the same effect.

19. Render! That's it!

At first you might not notice a difference because with the default settings of the SSS shader the effect isn't mind-blowingly better. But if you compare that render to your original that you 'kept' in the Render View, you should see a difference.

Now if you went and looked at the lightmap location on your hard drive (eg C:\mySuperSSS) you should see that saved file. You can view it using the imf_disp program if you like but it's not that exciting, hehe.

Have fun!! After some playing around and with the addition of Final Gather I ended up with this:




It was only after following Jozvex's excellent little mini-tutorial that I was able to figure out how to use the shader. It's not difficult once you've done it once or twice, but there's a lot of stuff to set up or it doesn't work at all. Thanks to Jozvex as always.

Jozvex
02-10-2005, 07:27 AM
Hehe, lucky my frustrated outbursts are useful.

:thumbsup:

MasonDoran
02-10-2005, 10:41 AM
useful?

more then that i think...lol


now if there was an easy way to actually bake the skin shader like in max....

MasterZap
02-10-2005, 07:42 PM
NOTE: Instead of that 19 step tutorial, why not go to www.lamrug.org (http://www.lamrug.org) and download the replacement to createAndAssignShader.mel which gives you one-click setup of misss_fast shaders.

Just your frendly neighbourhood spidertip ;)

/Z

Jozvex
02-10-2005, 08:45 PM
Uhhgrrrrrshh!! Curses!! Foiled again by that wretched spidertip guy!!

You haven't seen the last of me and my 19 step instructions!!

MasterZap
02-10-2005, 08:59 PM
:)

To be continued next week, same bat time, same bat channel....

/Z

dagon1978
02-10-2005, 11:54 PM
NOTE: Instead of that 19 step tutorial, why not go to www.lamrug.org (http://www.lamrug.org) and download the replacement to createAndAssignShader.mel which gives you one-click setup of misss_fast shaders.

Just your frendly neighbourhood spidertip ;)

/Z
it work with maya6.5?

Michael_Kasper
02-11-2005, 12:03 AM
Dear Zap.......ummm....how the hell do i get that mel script running? I've tried various commands but cant seem to hit it.....thanks.

Jozvex
02-11-2005, 01:15 AM
If you just put it in your regular scripts folder it'll take priority over the normal way the shaders are applied through the right-click menus in the viewports.

craigs
02-11-2005, 05:26 AM
Thanks Guys for imfo, but no joy, followed your instructions exactly, but strangly when I execute a render, mental ray just bombs out before even starting the render, it doe'snt even make an attempt to render the image..
so strange, any ideas.
cheerz
craig

BillSpradlin
02-11-2005, 09:35 AM
The script editor and output window are good places to start when diagnosing rendering issues.

craigs
02-11-2005, 06:09 PM
This is what the output window gives me!

API 0.0 error 301032: while defining material "misss_fast_skin_maya1SG": undefined shader "misss_fast_skin_maya1"
API 0.0 error 301031: call to undeclared function "misss_fast_skin_maya"
API 0.0 error 301032: while defining material "misss_fast_skin_maya1SG": undefined shader "misss_fast_skin_maya1"
API 0.0 error 301031: call to undeclared function "misss_fast_skin_maya"
API 0.0 error 301032: while defining material "misss_fast_skin_maya1SG": undefined shader "misss_fast_skin_maya1"
API 0.0 error 301031: call to undeclared function "misss_fast_skin_maya"
API 0.0 error 301032: while defining material "misss_fast_skin_maya1SG": undefined shader "misss_fast_skin_maya1"
API 0.0 error 301031: call to undeclared function "misss_fast_skin_maya"
API 0.0 error 301032: while defining material "misss_fast_skin_maya1SG": undefined shader "misss_fast_skin_maya1"
API 0.0 error 301031: call to undeclared function "misss_fast_skin_maya"
API 0.0 error 301032: while defining material "misss_fast_skin_maya1SG": undefined shader "misss_fast_skin_maya1"

Jozvex
02-11-2005, 08:05 PM
I think you must be using Maya 6 and haven't quite installed the shaders properly.

Did you edit the maya.rayrc file and add the new line?

azshall
02-11-2005, 11:03 PM
Misss_Fast_Skin_Maya and renderfarms.

.... I tried using this shader at work, and we have a nice size render farm. Problem is, I couldn't get sequential light maps. My renders didn't calculate properly at all. The render looked great, but ... with the farm rendering 50 frames at a time, and writing the same lightmap file 50 times at the same time.. it broke down pretty quick.

My question is ... Does anyone have a work around for this? Doesn't make sense to have to be able to only write 1 map...

Seth

BillSpradlin
02-11-2005, 11:51 PM
Don't put a file name in the slot for the map file and it will just keep it in the memory buffer instead of writing it to disc.

azshall
02-11-2005, 11:54 PM
interesting ... i did try this, and i didn't get the SSS result if i didn't physically write out the map. i'll do another test of this and see how it works, thanks for the tip ...

az

craigs
02-12-2005, 01:50 AM
No I don't think I did, what do you need to add, I have all the mental ray shaders listed in my create options within the hypergraph, is this what you mean???

cheerz
craig

BillSpradlin
02-12-2005, 02:11 AM
It should work that way (I've been using it on our renderfarm with that method just fine through Smedge) without any issues. Keep us updated if it's not working and I'll be more than happy to help.

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