Importing/replacing shaders

[gnimmel]

Is there a way in Maya (or perhaps a script exists) to import a shader to a scene which already contains the same shader, but insted of the shader being duplicated, make it replace the old one.

I have a character animated in a various different enviroments and the lighters want to alter the shaders to make him fit in to each scene. Some of these scenes contain the same enviroment and lighting so they only need to alter the shader once, but we can't find a way to bring the new updated shader in to different scenes without it being duplicated and not updateing the old shader.

Thanks,
Richard

[gmask]

In the multilister you can select all the shapes that a shader is assigned to and then assign the new shader to them.

[dylanmaxwell]

if you're having to do this repeatedly, or having linking issues What i would do is set up a layered shader with your shader as it;s only imput. then swapping the connections becomes very simple.
But no, There is no automatic method (that i know of)
-D

[gnimmel]

Thanks for the replys, looks like it's time to write a mel script.
Gmask : This is how we are doing it at the moment, but some of these characters have 20 + textures, it's just a pain in the butt to do it multiple times over multiple scenes.

Thanks,

Richard

[gmask]

Here's some code that will help you do that...

Let's say you have a shander named CRIMP and you want to know what shapes are using it.

string $name="CRIMP";
select $name; //selects all the shapes
or
sets -q $name; //lists all the shapes

You could then assign the list of shapes to an array and rename then as such or reassing a different shader.

string $Shapes[]=sets -q $name;

for($node in $Shapes){
rename $node ($node+$name);

}

Here's the code to see what shader is assigned..

listSets -ets -object nurbsSphere1
// Result: CRIMP //

If you wanted to get really fancy you could turn this shader substitution into a prerender script and not have to go through each file before you render.. it would just happen automatically.

[gmask]

//Here's the basic script to do the shader subsitution

select -all;

string $Shapes[]=ls -l -sl;

for($node in $Shapes){
string $shader[]=listSets -ets -object $node;

 switch($shader[0])
{
case "CRIMP1":
print("CRUMP1n");
sets -e -forceElement CRUMP1 $node;
break;
case "CRIMP2":
print("CRUMP2n");
sets -e -forceElement CRUMP2 $node;
break;
}

}

[gmask]

Here's how you would embed the script in your scene so that everytime you render it updates and assigns the correct shaders.

string $code="select -all;
string $Shapes[]=ls -l -sl;
for($node in $Shapes){
string $shader[]=listSets -ets -object $node;
switch($shader[0])
{
case "CRIMP1":
print("CRUMP1n");
sets -e -forceElement CRUMP1 $node;
break;
case "CRIMP2":
print("CRUMP2n");
sets -e -forceElement CRUMP2 $node;
break;
}
}
";

setAttr defaultRenderGlobals.preRenderMel -type "string" $code;

[gmask]

BTW .. I remember seeing script awhile back that woul dopen a folder of scene files one at a time and run a script over and save it. That way as longs as your reassinging the same shaders in each scene you don't have to do each one manually.

[gmask]

Hey if you really want to to these subs fast you could try this...

using www.Perl.org and www.cygwin.com if you are on windows I have made a script that would install the that MEL script in your ascii scene files in a jiffy.

Here's the command:

// This command pipes the source file into a variable.Then we go through the test2.ma and a line at a time look for the entry that is for the prerender script and then sub the sourced variable. The -i option makes a backup copy of the original file//

cat source.txt | perl -i.bak -p -e 'BEGIN{while(){print $_;$I=$_}};s/setAttr ".prm" -type "string" "";/$I/ige' test2.ma

In the source.txt file there would be the prerender script that you copied from the ascii of another scene file.. it should be in one line of text in that file. THe source also contains a MEL script that imports a file with the new shaders in it.

setAttr ".prm" -type "string" ("file -import -type "mayaAscii" -gr -rpr "shaders" -options "v=0;p=17" "C:/TEST/shaders.ma";rselect -all;rstring $Shapes[]=`ls -l -sl`;rfor($node in $Shapes){rstring $shader[]=`listSets -ets -object $node`;r    switch($shader[0])rt{rtcase "CRIMP1":rtprint("CRUMP1n");rtsets -e -forceElement CRUMP1 $node;rtbreak;rtcase "CRIMP2":rtprint("CRUMP2n");rtsets -e -forceElement CRUMP2 $node;rtbreak;rt}r}r");

[jeffd]

Btw, if you want to keep the original shader instead of substituting the new one, check out my importCleaner script. This will basically will consolidate those imported dupes to use the original. It also consolidates sets and layers, if you like.

--JeffD