How to execute a script on loading a scene?

[Anonymous]

I made a little script that switches fog on/off depending on the z position of a camera. (A greenish fog is switched on when the camera goes below sea level...)

callbacks.addScript #preRenderEval "mlbSwitchUnderwater()" id:#mlbUW

fn mlbSwitchunderwater = 
(
    mlbCamera = $Camera04
    mlbFog    = getAtmospheric(1)

    if mlbCamera.position.z > 0 then
        setactive mlbFog false

    else
        setactive mlbFog true
)

However i keep forgetting to run the script when I load the scene. So I rendered an animation and it turns out the fog didn't do its thing.

Is there a way to embed a script in a scene, so it is executed when the scene is loaded??

MLB

[Anonymous]

Have you tried this callback?

#filePostOpen:

I've used the following to add a popup when a file is loaded

clbckExecSTR = "messageBox \""+ message_body + "\" title:\"" + message_title + "\""
callbacks.addScript #filePostOpen clbckExecSTR id:#onload_message persistent:true

Hope this helps.

[Anonymous]

I tried it. Like so:

callbacks.addScript #filePostOpen "mlbUnderwater()" id:#mlbUW persistent:true

fn mlbUnderwater =
(

    callbacks.addScript #preRenderEval "mlbSwitchUnderwater()" id:#mlbSUW

    fn mlbSwitchunderwater = 
    (
        mlbCamera = $Camera04
        mlbFog    = getAtmospheric(1)
    
        if mlbCamera.position.z > 0 then
            setactive mlbFog false

        else
            setactive mlbFog true
    ) 

)

now it tries to execute something when i open the file, but i get this error message:

-- Error occurred in anonymous codeblock
--  Frame:
--   mlbUnderwater: undefined
>> MAXScript Callback script Exception: -- Type error: Call needs function or class, got: undefined <<
--   called in anonymous codeblock
--  Frame:
--   mlbUnderwater: undefined
>> MAXScript Callback script Exception: -- Type error: Call needs function or class, got: undefined <<
--   called in anonymous codeblock
--  Frame:
--   mlbUnderwater: undefined
>> MAXScript Callback script Exception: -- Type error: Call needs function or class, got: undefined <<

Any ideas?

MLB

[Anonymous]

Now whenever i open the file it tries to execute something. How do I remove the code from the file?

MLB

[Anonymous]

To remove your script from a file, use

callbacks.removeScripts #filePostOpen id:#mlbSUW
callbacks.removeScripts #preRenderEval id:#mlbSUW

I am looking at your problem, but haven't figured out why it's not working yet (might have to wait for my coffee break, have meetings this afternoon)

EDIT: not sure if the above is correct, but it's callbacks.removescripts that you need to look at in the help for the exact syntax.

EDIT2: There is a box for scripts to be run before rendering in the render rollout, don't know it that's suitable for your code for this one.

[Anonymous]

Thanks!

I managed to remove the scripts following your suggestion.

Also your sugggestion to use the render rollout works fine!

MLB

[Anonymous]

Yay! glad it all worked out (and also glad I don't have to fix your script, I hate callbacks, I always manage to make a mess of it)

🐵