How To Use .mi Fragments?

[dickagm]

Hi, I'm in situation with heavy geometry (2 million polys), and have to render a few diferent passes with it, phong, occlusion and mvectors. the problem is that every time that I'm starting render the exporting of that geometry is slowing down the whole thing with about 5 mins for frame and mi file becomes around 150mb. What I want to do is exporting it as scene fragment and include it in curent maya scene like a reference object. The problem is that there's no much info how this is happening and I'm still newbie with coding. I've tryed to export a cube with diferent options for scene fragment to use objects and materials but there is some error on rendering, like undeclared "lambert1". I've tryed with "declare shaders" option and then the warning disappears but again no cube in the render. Also I'm using Custom Global Text to add

$include "z:\mentalray\cube.mi"

At all I'm not shure is that the method or I'm totaly wrong because there is so little info about. What I'm missing? Please can someone explain what is the workflow for using scene fragments?
10x in advance

[dickagm]

ok I've found it,
After including the mi fragment (my geometry) in the Global Text:

$include "z:/my_lambert_shader.mi"
$include "z:/geometry.0003.mi"

for appearing in the render there must be set another custom text for Scene Text:

instance "myCube" "pCubeShape1"
material "lambert1"
end instance

this is making an instance with name "myCube" of the included object (only instances can be rendered) and
also connects material to the instance object.
and another additive custom text for Root Group Text:

"myCube"

this will add "myCube" in the renderworld in final mi scene and thats it
hope this will help to someone

But I have another problem, how can I make the custom text to use attributes from maya?
I need to control the incrementing number of the included mi files.
can I do something like mel $include ("z:/file."+$my_attribute+".mi")
I dont have idea what to do. Only thing that I have in mind is to make a 100 custom text nodes and to
switch between them on changing the frame. this sounds crazy, there must be an inteligigent way. I know
that I have to read the whole mentalray help for clearing these thing but at the moment I dont have time
and the project I'm working on is going closer to the deadline. Please give me a point.
Thanks in advance

[dickagm]

I don't like to leave the things unfinished and will post another answer to myself,
the custom text node can be controled with "setAttr" by using this expression:

---

setAttr -type "string" "mentalrayText1.text" ("$include \"z:/mentalray/water/water.mi."+(frame+1)+"\"\n$include \"z:/mentalray/shaders/water_shader.mi\"");

this will add the folowing text in to the custom mentalray text node :

$include "z:/mentalray/water/water.mi.0"
$include "z:/mentalray/shaders/water_shader.mi"

---

And again I hope that there can be found more usefull info on these forums, but this will happen only when talking each other. sharing ideas

[joojaa]

Well i tought abouit aswering you 2 times, first time you had posted about a hour before i was about to post (i had flaggetd it to answer this, but i needed to chek my generators since i dont remeber everything offhand), next time since you were allready doing so muh progress i tought better to leave you figuruing it out yourself because it was trivial mel usage you could easily echo on screen.

Personaly I do it in 2 possible ways.

include a file that includes rest of files. and use awk or pythonform my commandline render to do the search and replace. (actualy python scne it might be i generate the stuff on rendertime)

have one prerenderFrame lmelscript that parses ALL mi text files trough a globel substitute regexp changing some notation like %f% to framenumbers or eval contents of a match (thiway i could wirte %f-10%)