topic Re: the referencing of a controller in MaxScript in 3ds Max Programming Forum

the referencing of a controller in MaxScript

richardGRWZS — Mon, 02 Oct 2023 09:07:40 GMT

Hello everyone,

I'm a beginner and I'm stuck with the logic of the referencing of a controller in MaxScript.
I'm trying to create a script that requires referencing a controller that has either been created by a script or not. Despite reading the documentation, I'm feeling a bit lost...

Is it possible to give a name to a controller when it's created? (the MaxScript listener remains silent when I rename it manually). I tried to add, without success, the line 'fs.name = "my_controller_name"' just after 'fs = Float_Expression()'.
If not, how can I reference a 'Float Expression' controller since MaxScript doesn't seem to recognize the syntax 'Float Expression.controller' or 'Float_Expression.controller'?

masterRot = $Wheel_00 -- Point gizmo creation pointObj = Point box:on size:5 pos:selectedObj.pivot -- Add Float Expression controller to the point object pointObj.rotation.controller.Z_Rotation.controller = float_list () fs = Float_Expression () pointObj.rotation.controller.Z_Rotation.controller.Available.controller = fs -- //!\\ problematic line doing error: trying to do a connection with a controller on an other object masterRotCtrl = execute (masterRot.name as string +".rotation.controller.Z_Rotation.controller.Float Expression.controller") -- Filling the expression of the float expression controller fs.addScalarTarget "Rot" masterRotCtrl fs.addScalarConstant "n" nT fs.addScalarConstant "nR" nTR fs.SetExpression "-Rot/(n/nR)"

Thank you in advance,

Re: the referencing of a controller in MaxScript

denisT.MaxDoctor — Mon, 02 Oct 2023 09:46:52 GMT

cc = float_list() ln = cc.available.controller = linear_float() cc.setname 1 "Linear" ex = cc.available.controller = float_expression() cc.setname 2 "Expression" cc[#linear].controller == ln cc[#expression].controller == ex

Re: the referencing of a controller in MaxScript

richardGRWZS — Mon, 02 Oct 2023 11:41:54 GMT

Thank you for your response!

I understand now how to set a name, I'm almost there. But there is still an unknown area for me:
If I understand correctly, a controller is like an object that you need to know the path to access, but I didn't understand how I can "reconstruct" this path when I don't have access to it directly in a variable !

If I take back my exemple updated with your explanations:

masterRot = $Wheel_00 -- Point gizmo creation pointObj = Point box:on size:5 pos:selectedObj.pivot -- Add Float Expression controller to the point object local cc = pointObj.rotation.controller.Z_Rotation.controller cc = float_list () cc.available.controller = linear_float() cc.setname 1 "Manual_Adjst" fs = cc.available.controller = float_expression() cc.setname 2 "SlaveRot" -- Filling the expression of the float expression controller -- //!\\ Problematic line: "syntax error: at [, expected name" masterRotCtrl = execute ("$"+ masterRot.name as string +".Rotation.controller.Z_Rotation.controller.[#SlaveRot].controller") fs.addScalarTarget "MasterRot" masterRotCtrl fs.addScalarConstant "n" nT fs.addScalarConstant "nR" nTR fs.SetExpression "-MasterRot/(n/nR)"

So there is something wrong with this line 16 because i still don't anderstand how to build the path to target a specific controller :
masterRotCtrl = execute ("$"+ masterRot.name as string +".Rotation.controller.Z_Rotation.controller.[#SlaveRot].controller")

I tried with [#SlaveRot] > syntax error: at [, expected name

I tried also simply with 'SlaveRot' > error: Unknown property: "rotation" in undefined

Thank you again in advance

Re: the referencing of a controller in MaxScript

istan — Mon, 02 Oct 2023 15:07:39 GMT

As you want to use "execute()" I'd enter

$MASTERROTNAME.rotation.controller.Z_Rotation.controller.[#SlaveRot].controller

in the MXS listener and check why this line is outputting an error..

Re: the referencing of a controller in MaxScript

richardGRWZS — Mon, 02 Oct 2023 16:25:32 GMT

You think the logic of the syntax is good but it's just a problem with my actual scene test ?

Here is a screenshot of my test with the manual request in the listener:

Re: the referencing of a controller in MaxScript

denisT.MaxDoctor — Mon, 02 Oct 2023 19:24:28 GMT

You're working with expression controllers the wrong way....

(I'm not talking about syntax errors now, but the concept as a whole)

look at my example, use MXS help to understand, ask questions if something is not clear:

( delete objects bx = box wirecolor:green cn = cone wirecolor:orange bx.height.controller = linear_float() z_ex = cn.pos.controller[3].controller = float_expression() z_ex.addscalartarget "rise" bx.height.controller -- one way to pass a controller z_ex.setexpression "rise" h_ex = cn.radius1.controller = float_expression() h_ex.addscalartarget "base" bx.baseobject[#height] -- another way to pass a controller h_ex.setexpression "base / sqrt(2)" )

This example uses expression controllers to bind the 'z-position' and 'radius 1' of the cone with the height of the box.

Re: the referencing of a controller in MaxScript

richardGRWZS — Mon, 02 Oct 2023 22:44:14 GMT

Thanks a lot for your help !

I feel stupid it tooks me so long to get it 😅
It works fine for me now, so you can find below the modified code with what I understood from your comments:

masterRot = $Wheel_00 -- Point gizmo creation pointObj = Point box:on size:5 pos:selectedObj.pivot -- Add Float List controller to the point object fs = pointObj.rotation.controller[3].controller = float_list () -- Rename the default "Bezier float" controller fs.setname 1 "Manual_Adjst" -- Création and filling the "Float Expression" controller cc = float_expression() masterRotCtrl = execute ("$"+ masterRot.name as string +".rotation.controller[3].controller.SlaveRot.controller") cc.addScalarTarget "MasterRot" masterRotCtrl cc.addScalarConstant "n" 10 cc.addScalarConstant "nR" 40 cc.SetExpression "-MasterRot/(n/nR)" -- Apply the "Float Expression" controller and rename it fs[2].controller = cc fs.setname 2 "SlaveRot"

If it can help other noob like me 👍
Thanks again and please don't hesitate to provide further feedback on the script exemple, even if it's working fine!

Re: the referencing of a controller in MaxScript

denisT.MaxDoctor — Tue, 03 Oct 2023 00:01:26 GMT

@richardGRWZS wrote:

masterRotCtrl = execute ("$"+ masterRot.name as string +".rotation.controller[3].controller.SlaveRot.controller")

It doesn't make sense to me. That's how it should be:

masterRotCtrl = masterRot.rotation.controller[3].controller.SlaveRot.controller

Re: the referencing of a controller in MaxScript

richardGRWZS — Tue, 03 Oct 2023 01:06:41 GMT

You are absolutely right; it's a remnant from the original script that I haven't cleaned up.

In my original script, 'masterRot' doesn't directly target the object I want. I need to add the prefix 'H_' to get it.
This results in: execute ("$H_"+ masterRot.name as string + "...")

Re: the referencing of a controller in MaxScript

denisT.MaxDoctor — Tue, 03 Oct 2023 03:17:54 GMT

@richardGRWZS wrote:
You are absolutely right; it's a remnant from the original script that I haven't cleaned up.
In my original script, 'masterRot' doesn't directly target the object I want. I need to add the prefix 'H_' to get it.
This results in: execute ("$H_"+ masterRot.name as string + "...")

Using "execute" is completely irrelevant in this case.