Hi there,

Is there a way to derive hotl-like information about an operator inside an OTL?

i.e, to get the label of an operatortype in some otl, something like:

Director -> hotl -e Object/test_asset myotl.otl
Test Asset
Director ->


In a sense, like the “optypinfo” expression that works on operator-types in external otls.

Is this currently possible? If not, any nice workarounds and a possible RFE?

Thanks,
Jason

Hi Jason,

I second that RFE. Actually; it would be nice to have a full set of query/manipulation tools for otl files. Something like the “ot…” expression functions, but for the actual otl files.

In the meantime, you can do the usual hack and use hotl through a system() call. So, you can start with:
textport-> echo `system('hotl filename.otl')`
(I'm assuming you want this from inside houdini)
If you just want a list of the operator labels, and nothing else, then use "hotl -B filename.otl“.

To actually get something like optypeinfo, you'd need to do a little parsing but, again, you can resort to piping the result of the ”hotl filename.otl" call to your favourite scripting language. For example; to just get the value of each field and ommit the field's labe (since the number/type of fields is fixed)l, you could:

textport-> set filter = “awk -F \”:\“ ‘{ if(NR>1) {gsub(/^\\ */,\”\“,\$2); print \$2;} }’”
textport-> echo `system('hotl filename.otl | $filter')`

That's using awk, but you can choose your own favourite poison
And finally, wrap the whole thing up as a custom expression function as usual…

If you need more detailed inspection than what hotl gives you, you'll have to write a little shell script to expand the otl, perform the query, and clean up after itself. Not hard, but definitely a pain.

Yup. This kind of thing should be available as a shell tool. If for no other reason, it would give us a stable API to a format that is *bound* to keep changing for some time (meaning we'd need to update our hacky workarounds for each version…<sigh>).

RFE! RFE!

Great Mario, thanks!

Sigh, I was hoping I'd missed something in the ot* commands, but I think you're right and I'm going to have to parse up the output of “hotl”. I'm always trying to avoid system() calls because they always pop up a shell window in Windows and cause epileptic reactions. :wink:

Thanks for the code snippet too, I'll bastardize that for my nefarious purposes.

Cheers,
Jason

Here is what I used eventually. Ugly, but it did the job.

–hotlinfo.pl PERL script

#!/usr/local/bin/perl
# assumes usage:
# hotlinfo operatorname info otl
# e.g. hotlinfo mysop Label myotl.otl
#
if(!defined($ARGV)) {
print STDERR “ usage: hotlinfo operatorname info otl\n e.g. hotlinfo mysop Label myotl.otl\n”;
exit 1;
}

$curop=“”;
my %nodes;
$match=0;
open(HOTL,"hotl $ARGV |“) or die;
while(defined($line=<HOTL>)){
chomp($line);
if (length($line)){
($token,$value)=split(”: *",$line);
$match=1 if($token=~/Operator/ && $value=~/$ARGV/);
$match=0 if($token=~/Operator/ && $value!~/$ARGV/);
print $value if($match && $token=~/$ARGV/);
}
}
close(HOTL);


edit: bugfixed

Since you came up with a work around…i'll give you the “in houdini” answer now.

otls will give you the same thing.
otls [otl_path} will give you a list of all the types inside of an otl
otls table/type will give you all the extra info you need.



/ch/ch1 -> otls PHoudini_Projects/cubedood/houdini/otls/timeMachine.otl Object/timeMachine
Operator: timeMachine
Label: Time Machine
Path: oplibObject/timeMachine?Object/timeMachine
Icon: opdefObject/timeMachine?Icon
Table: Object
Extra:
Inputs: 0 to 1
Subnet: true
Empty: false
Modified: Sun Sep 28 10:51:13 2003



foreach table_type (`run(“otls /tmp/my_Stuff.otl”)`)
otls /tmp/my_Stuff.otl $table_type
end


jim.

AhHa!…. missed that one…

Thanks Jim!

Ah yeah,

Thanks Jim.. Now to get some of those fields extractablized (nu-english). That would make an RFE still, wouldn't it?

String processing with arg() and match(), here we come.

Cheers!
Jason

If you can wait until 6.5 is released, don't bother spending too much time on those parsing routines… otls will let you specify exactly what data to output and in what order, without the labels. But please don't ask me when 6.5 is going to be released…

Mark

Ah, thanks Mark!

Those functions will be very useful.