Forests in maya mental ray.

#541

are you fella’s lighting your scenes with IBL? Raytraced shadows?

#542

Raytraced shadows, yes, but I rarely use IBL. Instead I’ll use Sun/Sky and then make a few reflector plates of actual sky photos or images (stock from friends) to enhance the off-scene reflections. Very subtle difference, but it helps. IBL would also be helpful I suppose, but I’m not sure how well it works with just FG, and I don’t intend to use GI for such scenery in the future unless the job or scene actually needs caustics.

Depth-Map shadows don’t work very well at all for realism with heavy geometry and mia_materials.

#543

I’ve updated the resume doc to all the thread.
A couple of things to say:

-This is only a big cut’n’paste of the most useful words written in this awesome thread. Nothing was added by me. I’ve highlighted (in red) some points that I believe important.

-I didn’t include examples if they weren’t used for explanations or tips; I prefered focusing on techniques.

-I’ve tried to be as general and complete as possible with the selection. Many issues of interest could although have been cut. For instance, I didn’t include the Rasamaya memory tests as I was more interested in other aspects, but with no doubt those were interesting to many.

-I could have forgotten to include some subjects

-I think Tostao_Waynes is not a man. He’s an Autodesk ai-bot like Ghost in the Shall Puppet Master that have answers hardcoded in his circuits :smiley:

Anyway, I thought that this could be useful…

Forests.in.maya.mental.ray.thread.resume.02.pdf

http://www.mediafire.com/file/ktu2tyowrq5m3ze/Forests.in.maya.mental.ray.thread.resume.02.pdf

If you see some indispensable subject not included let me know, I will update the pdf.
:deal:

#544

Excellent write-up arkanoid! Thank you for taking such time to write a very well explained, compressed pdf of this thread.

#545

thanks for the write up :slight_smile:

#546

Nothing guys. This thread deserved it :slight_smile:
Off course if someone would put the link to one of the first posts in the first page this would be great.

#547

ok, I’m kinda’ lost in here… if I understood it correctly it’s not possible to use it on a multiple mesh object unless I combine them and use some UV sets, right?

e.g.: a scene with 500 cars, but the original one was modeled in multiple pieces.

this proxy thing is confusing, at least for me :slight_smile:

#548

ok, I’m kinda’ lost in here… if I understood it correctly it’s not possible to use it on a multiple mesh object unless I combine them and use some UV sets, right?

e.g.: a scene with 500 cars, but the original one was modeled in multiple pieces.

I don’t use Proxies, but the concept is the same. You materialize your objects beforehand. Then, when combined, the combination objects keep all their respective shaders on a per-face basis. This is how it works with instancing, anyway. So when I need to select those objects, I go to their shader in Hypershade and right-click-drag to “Select all Objects with Shader” or whatever. So you still have them isolated for selection, if required.

#549

but I’ll have to layout my UVs for the high poly object (before combine all meshes) in 1,1… 1,2… 1,3… and so on, right?

#550

How are proxy’s different from instances?

#551

Proxies source an outside file, I believe. I don’t use them yet. Instances are simply duplicate shape nodes with unique transforms. I believe they have the same benefits, but with instancing your original shape node needs to be in the scene as well. With proxies, you could make a 2d “card” object as your proxy, with the source shape coming from a file outside your scene.

Either way, at rendertime you’re only loading in one shape node per proxy/instance type. This saves on RAM and rendertime considerably.

#552

no necesary, you can combine the original object, after that take a look to the attribute editor to see the order of the shaders assigned to the final object (take a look to the tabs of the attibute editor to see the order) And assign the shaders in the same order to the proxy object, the first shader to the whole object, and the rest in order in face mode (the second to one face, the third to another face…)

#553

the instances must to be loaded into the interface, the mayor problem is that maya repeat the instance process each time you open the file.

If you have a complex object that must to be instanced 10.000 times, each time that you open the scene maya must to do again the instance process. in some cases it can take too much time.

If you use proxies, you only have a simple cube with the proxie assigned to it. the interface only need to load the cube or to instance a simple cube (be carefull the proxie is assigned to transform node, so a direct intance will not copy the conection to the proxy). the proxy geometry will be loaded only at rendertime

#554

I’ve been working on a script that might be useful to some people here. Just wanted to contribute something back, having learned a ton from this thread.

I know someone previously made a script to distribute pfx leaf uv’s randomly, but I started getting into scripting recently, and wanted to take a stab at it too!

I’m no expert, and the script isn’t finalized, but it works.
One thing to note: it creates an undo for each action, so you may not be able to undo back to where you were… I’d save the scene, or duplicate the geometry you’re working with first.

It’s on my downloads page Here
or a direct link Here

Hope it’s useful!

Uploaded with ImageShack.us

#555

Amazing script! Very extensive, and the GUI is helpful. Thanks for all your work on this one!

#556

Thanks!

One other thing I forgot to mention about the uv’s…

If a “leaf” has more than 4 verts per face (divisions etc) then it will still calculate, but take quite a bit longer.
Because of that, I made it to where you can select multiple Leaf mesh geometries, and run the script for the single mesh option, and it will loop through all the meshes selected. Useful if you want to run it overnight on your entire set of plants, or trees.

#557

the uv’s randomly is very usefull.

#558

Indeed, if anyone has any recommendation, or thoughts or find any bugs, let me know. I’m always looking to improve it.

#559

Stuck in an endless “Processing Download Request” while trying to download your .pdf…

#560

Thank you for the replies Tostao and Sho Pi.

Just made a small observation on the stand-in geometry when working on my grass - be sure to freeze transforms if you scaled the object, or it appears you get a double-transformation on the proxy objects.