OTL sop paths and Expressions tip

[kni8_2k]

The problem :

Give the user the ability to pick a sop from an otl to use as the basis of instancing.

Allow the user to also put expressions in the path

I was looking through the forum at various ways to solve this problem, and what came up most was the

evals(chsraw("../somenode..")) method.

now perhaps my implementation was wrong, but it seemed like I could not get this expression working if it was a straight string that pointed at a sop, but it worked if my otl level path was something like :

Worked :

"/obj/firehydrant_"+($PT%2+1)

Did Not Work :

/obj/firehydrant

I could get it working for either method but not both.

The Solution was to create a switch node and use the following expression in it :

if(opexist(chs("../regular_path/instancepath")), 1, 2)

I added an empty add node to it, as a trick to keep the switch from erroring out.

What the expression does is just look at the path and see if it can find the sop (is it a direct path) if it can't it assumes that the input is an expression and tries the 3rd input which evaluates the path with : evals(chsraw("../instanced_Geo"))

If I am doing this wrong, please let me know.

If this help then I am glad I shared it.

Cheers,

Ali

[kgoossens]

Hey Ali, thanks a lot for this tip. Have been struggling with this!! Could you also add this tip to http://odforce.net/wiki/doku.php?id=gems ? Would be great if it was easy to find later on.

Cheers!

[kni8_2k]

HAH ! glad I could finally help, I'm usually looking to you guys for help !

I'll try to get the tip on that page.

cheers,