template for shader palette selection upon attachment

global proc yi_selector(string $phase)
{
string $paletteName ="";
string $s ="";
string $m ="";
string $b ="";
if ($phase == "normal")
{
$s = "/shows/tife/prod/surface/char/tife_c_yi/tife_c_yi_rig_h.splt";
$m = "/shows/tife/prod/surface/char/tife_c_yi/tife_c_yi_rig_h.surface";
$b = "/shows/tife/prod/surface/char/tife_c_yi/yi_sss_setup.mel";
}
else if ($phase == "wet")
{
$s = "/shows/tife/prod/surface/char/tife_c_yi/tife_c_yi_rig_h_wet.splt";
$m = "/shows/tife/prod/surface/char/tife_c_yi/tife_c_yi_rig_h_wet.surface";
$b = "/shows/tife/prod/surface/char/tife_c_yi/yi_sss_setup_wet.mel";
}
else if ($phase == "dirty")
{
$s = "/shows/tife/prod/surface/char/tife_c_yi/tife_c_yi_rig_h_dirty.splt";
$m = "/shows/tife/prod/surface/char/tife_c_yi/tife_c_yi_rig_h_dirty.surface";
$b = "/shows/tife/prod/surface/char/tife_c_yi/yi_sss_setup_dirty.mel";
}

$paletteName=`slimcmd slim CreatePalette -file $s`;
print "attach mel\n";
eval("source \""+$m+"\"");
eval("source \""+$b+"\"");

}
global proc surface_yi_selector()
{
if (`window -ex ABCWin`==true)
deleteUI -window ABCWin;
window -title "Select yi shader type" ABCWin;
columnLayout -adjustableColumn 2;
button -label "normal" -c "yi_selector(\"normal\")";
separator -h 10;
button -label "wet" -c "yi_selector(\"wet\")";
separator -h 10;
button -label "dirty" -c "yi_selector(\"dirty\")";
separator -h 10;
setParent ..;
showWindow ABCWin;
}
surface_yi_selector();

Old Maya Render Presets

There is no preset option to create a layer override in Maya 2009 as it was in 2008

However you can still create these overrides by using the following Mel
Where layer1 is the name of the Layer you like to override.

Ambient Occlusion

renderLayerBuiltinPreset occlusion layer1;

Luminance Depth

renderLayerBuiltinPreset linearDepth layer1;

Normal Map

renderLayerBuiltinPreset normal layer1;

Geometry Matt

renderLayerBuiltinPreset matte layer1;

Diffuse

renderLayerBuiltinPreset diffuse layer1;

Specular

renderLayerBuiltinPreset specular layer1;

Shadow

renderLayerBuiltinPreset shadow layer1;

From http://mayastation.typepad.com/