Where to put hscript commands?

[chrsmith]

Hi there,

I'm trying to run hscript commands at different points in my animation, including calling tk and manipulating objects. How is this done without typing it into the textport? Where do you put scripts/commands that will run at certain times?

Thanks,

Christine Smith

Northrop Grumman

Engineering Visualization Resource

[Jason]

I missed this one completely!

Did you get an answer? (LogicCHOP is usually the best choice)..

[michael]

it also has the coolest icon...

[pbowmar]

Hi Christine,

You can run any script pretty much anywhere you want. For example, you could put it in an unused channel. Let's say you had a simple script in $HOME/houdini7.0/scripts you wantred to run, let's call it "testmessage.cmd" that has this in it:

message This is frame $F

That's all it does

So, if you type "testmessage.cmd" in the textport it tells you what frame you're on.

Now, all you have to do is create a little wrapper custom expression. Open up the Alias/Variables dialog, and go to the Expressions tab.

Type this in:

string
runner(float curframe, frameToRun)
{
    if(curframe == frameToRun)
    {
        run("testmessage.cmd");
    }
}

Now, you can use the runner() expression in an unused channel. For example, I used the Renderman Cs in an Object, since I am not using Renderman, I don't need it. I just enter:

runner($F,50) and on frame 50 the script is run!

You have to wrap the running of the script in a custom expression, or else the script is run at times you don't want. When testing this, I first tried:

if($F == 50, run("testmessage.cmd"), 0)

however, this runs the testmessage.cmd A LOT which is annoying. The custom expression is the way to go.

Actually, now that I think about it, here's what the expression should really be:

string
runner(float curframe, frameToRun;
        string script)
{
    if(curframe == frameToRun)
    {
        run(script);
    }
}

So you then have a generic "runner" script that takes the current frame, the frame you want to run the script on, and the script itself, like so:

runner($F, 50, "testmessage.cmd")

Much more useful.

Cheers,

Peter B