Expression, Mel, And Fur

[12monkey]

expression, Mel, and Fur
What I want is use animated file sequence to animate the fur. for example I want animate the FurDescription.bcm( BaseColorMap ).

I tried using expresion to setAttr every frame, it's not working when batch render. one of my friends tells me, when batch render, only expresion works, mel command such as setAttr will not execute, I am not sure if it is exactly the case, but apparently setAttr wont works anyway.

After that I tried to use preRenderFrameMel. But again it's not working, and I found out Fur is actually been rendered before preRenderFrameMel execute, but even if fur is rendered before preRenderFrameMel execute, it should still work from the second frame, cuz after the fur in first frame been rendered, the preRenderFrameMel is executed, and the effect of mel should take place in second frame.

Here is the preRenderFrameMel, it's really simple:

CODE
setAttr -type "string" furDescription1.bcm ("fileName." + $padding + ".iff");
print ("fileName." + $padding + ".iff");

$padding is a string, and has been precalculated, and has no problem.
Since I printed out the string, so I'm sure the string I try to set is 100% correct. But It's just not working.

So how can I solve this problem?
Thanks in advance

[joojaa]

Actulally expressions should work but maya does not necessarily update all thing especially whan rendering with mental ray.

Mainly becasue theres no trigger to ask for the result. one trick is to set the attr and getAttring some downsteramplug thats needed. The main reason here is that its not keyable. Or try to force it with dgeval

however you might try the regexp node thet comes iwth the bonus tools.

[12monkey]

Thanks for greate Tip !!

So if I want to force it to update, I just put "dgeval furDescription1.bcm;" at the end of expression.

[12monkey]

And another question, how I tell whitch attribute will be updated, and whitch won't. Can I find some documents about such updating behavior, and where can I find it. (It seems Maya's help document doesn't mention anything about it)

Thanks

[12monkey]

dgeval is not working
I put dgeval at the end of expression. But when I batch render, it still only render the first frame(evry frame is same as first frame)

Maybe I should try regexp node, which version of bonus tool does this node come along with? And do they compatible with each other? cuz I only have Maya7.0

[joojaa]

Nononono...

don't eval a input of a node. it would be uneventful. You allready have evaluated it, evalueta the entire node dgeval furDescription1. Howevre it is totaly possible that mentalray will just ignore you totaly becassue its not marked being a attribute wich should update like this.