MtI 0.9

dougal2 · Post by **dougal2** » Tue Jan 01, 2008 2:02 am

yeah, it can be a bit quirky.

I've settled into a pattern of either starting scenes with a view to rendering in indigo OR mentalray/maya software. It's somtimes difficult to keep a scene 100% compatible with both.
(but then, I've still got tons to learn about Maya anyway

)

Phr0stByte · Post by **Phr0stByte** » Tue Jan 01, 2008 2:12 am

I have figured out how to use an exr for lighting, but for the life of me, still cant get mesh lights only to work... Same for nk mats.

dougal2 · Post by **dougal2** » Tue Jan 01, 2008 4:15 am

for meshlights only, it should be sufficient to just set the background type ("Env light") to "None"...
are you having trouble actually making a shader a meshlight, or just trying to use meshlights on their own?
What tonemapping settings are you using? If it's "camera" or "linear" it's possible that your meshlights are working, but your picture is under-exposed. reinhard should work the easiest.

As for nkdata the steps required are as follows (assuming you have the latest SVN MtI):
1. create a phong shader and assign it to your obejct
2. open the hypergraph, and select your phong shader
3. click the "Add NK Data" button on the "Shader Attrs" button shelf in MtI
4. expand the "Extra Attributes" section of the phong shaders atributes in the attribute editor.
5. choose an nk file preset.
(6. set the cosine power as necessary)

that should be it.

Let me know what you have difficulty with.

dougal2 · Post by **dougal2** » Wed Jan 02, 2008 10:24 am

re: Meshlights.

I know what the problem is... it's a change I made to the way meshlights are made from incandescent shaders.

and I've only just realised what's going on as I experienced the problem myself.

on your meshlight shader, set the glowIntensity attribute = light power in Watts. By default, it's set to 0 = no light

grr.

dougal2 · Post by **dougal2** » Wed Jan 02, 2008 11:58 am

a thought:
I can fix this probelm by detecting if power_drawn = 0, and setting it to a default, (and then printing a warning to tell you that MtI set the value).

Phr0stByte · Post by **Phr0stByte** » Wed Jan 02, 2008 1:27 pm

I solved the meshlight problem, but still having all kinds of issues exporting certain object - all modeled natively in Maya. I have come to the decision to just forgo Indigo with Maya and learn Mental Ray - LOVE that rendering speed!

dougal2 · Post by **dougal2** » Thu Jan 03, 2008 6:21 am

REV 194
Added GUI button to load an IGM on the current object selection.
Usage: Select objects, press button, find IGM file.
As per the specification for IGM, the created shading group will use the filename (no extension). If you wish to use a different material defined in the file, you will need to manually rename the shading group.
The created PhongE shader only serves to load the IGM via an <include> tag and is named [MaterialName]_Loader

Phr0stByte · Post by **Phr0stByte** » Sun Jan 06, 2008 11:20 am

dougal2
I am having no luck with the export script at all, as I am sure you are aware. If I just slap some primitives on a plane, there aren't any issues, but anything more complex than that I model, I get errors that are not comprehensive to me. I am attaching a download link of my fan model here: http://rapidshare.com/files/81574609/el ... b.zip.html

Please see if you can make sense of it.... I miss Indigo.

Meanwhile, here is a look at the latest Mental Ray tweaks to mats on the fan: http://www.renderosity.com/mod/gallery/ ... 592830.jpg

Nice Mat DB, by the way...

dougal2 · Post by **dougal2** » Sun Jan 06, 2008 11:22 am

ok, I'll have a quick look.

dougal2 · Post by **dougal2** » Sun Jan 06, 2008 11:50 am

1. Deleted history on the buttons (zero vert objects*)
2. silver was defined as an anisotropic shader, which MtI and Indigo don't support -> changed to phong
3. the fan blades were using a mentalray shader, which MtI/indigo don't support -> changed to phong

( * I'm fairly sure this is actually a bug in the OBJExport plugin )

If indigo crashed when loading objects, you can still copy the offending object name out of it's log window, and then enter

Code: Select all

delete <paste object name>

into Maya. Especially if the name is something like |groupN|pObjectX|polySurfaceShape1 - this is just a history item that can be safely deleted.

quick render with HDR lighting:

Phr0stByte · Post by **Phr0stByte** » Sun Jan 06, 2008 12:02 pm

dougal2
Thats great to know that I can delete the entrys. On mats: As management is quite a bit more dificult than I am used to in Blendigo, will your exporter at least export the name of the fancy mr mats, so that it can be edited in the xml by hand?

dougal2 · Post by **dougal2** » Sun Jan 06, 2008 12:23 pm

It appears to be exported as part of the .obj file.

-group8-polySurface24-polySurfaceShape24.obj, line 10199:

Code: Select all

usemtl mia_material3SG

although Indigo doesn't complain about the missing material - it just fails to render the object at all!

I tried to define my own material mia_material3SG in the .igs - and it made indigo crash

Looks like you have to re-assign a material in Maya before exporting.

Phr0stByte · Post by **Phr0stByte** » Sun Jan 06, 2008 12:35 pm

dougal2
Actually, I still cant get the stuff deleted - it wants me to delet my buttons! maybe you can write down the exact steps you took to clean this up - sorry, it just seems that the script is low on features but high on complexity. (I dont mean any disrespect, as your efforts are GREATLY appreciated, but have you looked at Blendigo? High on features, easy to follow).

dougal2 · Post by **dougal2** » Sun Jan 06, 2008 12:39 pm

you need to specify the "full path" for the objects.
sorry I did type this out once, then firefox crashed and I couldn't be bothered to type it again *sigh* .. this is the full object name:

Code: Select all

delete |group6|pCylinder7|polySurfaceShape1

you should see no change in your objects after running this command, but it'll keep Indigo happy.

Re: the script...
it's supposed to be fairly low on features, so that clicking export renders the scene pretty much as it appears in Maya.
I agree there's a few things that could be smoother in the export process though - the history meshes being one of them. The scene translation is quite a tricky process.

I don't think that blendigo is any easier to use, and personally I dislike the way that all materials have to be (re-)created within the blender script. you don't necessarily see in the viewport exactly what renders. MtI is much better in that respect IMO (hell, it even copies all your textures for you!).

MtI is also under a couple of constraints from Maya - we can only export objects in .obj for now.
Another option would be to build a native Indigo mesh export module, but that would take a lot of work, and would probably be slower.

Phr0stByte · Post by **Phr0stByte** » Sun Jan 06, 2008 12:46 pm

dougal2
OK - but how do I get that full path? For example, my next model.... I need to know how to do it on my own, so I am not bugging you all the time. ( I think you are very lucky that there is not a huge Maya community here in the Indigo forum....)