NodePath.ls() doesn't return anything

Scripting Issues
1

Hello, I am trying to use the NodePath.ls() function, but it simply does not print anything. No errors either. What am I doing wrong? Here is an image of the console where I typed the function.
image
As you can see, app.scene has 69 children.
I hope you can help me. Thank you!

2

Are you sure that you call this on the node? Try on the render.ls()

3

I am not sure exactly what I am doing, but I tried to follow the manual. Trying it on render doesn’t work either.
image
Any ideas?

4

There are no ideas since you did not provide the code.

from direct.showbase.ShowBase import ShowBase

class MyApp(ShowBase):

    def __init__(self):
        ShowBase.__init__(self)

        self.model = self.loader.loadModel("box")
        self.model.reparentTo(render)
        print(render.ls())

app = MyApp()
app.run()

PandaNode render S:(CullFaceAttrib RescaleNormalAttrib)
  ModelNode camera
    Camera cam ( PerspectiveLens )
      PerspectiveLens fov = 50.942 30
  ModelRoot box.egg
    GeomNode box (1 geoms: S:(TextureAttrib))
None
5

Here is the code: https://pastebin.com/tpnsCfpS
It is pretty awful, I know, I just use it for learning the engine.

As you can see, I added print(render.ls()) in the __init__ function, where I executed it from the console before, but it still returned None. I also tried changing render to self.scene as that is what I reparent most objects to. Still no ouput. I also tried adding the line in the load_scene function, as that is where I reparent all the objects. Still no output.

I find it really weird. Perhaps I should try with one of the sample projects instead.

Edit: I just tried to add print(render.ls()) in the end of __init__ function of the glow-filter sample project. I am still getting None as output.

6

Does the code I provided work for you? Just check it out.
I suspect a problem with your terminal, maybe it just displays one last line. Take a look at the panda console.

7

Hello!
What is your version of Panda3D?

8

The “ls()” method doesn’t return a string to be printed–it prints the results itself, I believe.

That is, the “print”-statement is superfluous–just calling “render.ls()” (or “someOtherNodePath.ls()”) should be enough.

(Although, while this explains the “print”-statement writing out “None”, I’m not sure of why “ls()” isn’t printing anything despite the “print”-statement–it should, I believe.)

What happens if you just print “app.scene”? That is, if you run “print (app.scene)”?

9

I am 100% sure that the problem is with the IDE. It displays only one line.

PandaNode render S:(CullFaceAttrib RescaleNormalAttrib)
  ModelNode camera
    Camera cam ( PerspectiveLens )
      PerspectiveLens fov = 50.942 30
  ModelRoot box.egg
    GeomNode box (1 geoms: S:(TextureAttrib))
None

This - ^

10

As @Thaumaturge points out, render.ls() always returns None, after printing the list to the notify output (which I think is stderr by default).

If you want to capture the result in a string, you should pass a StringStream as the argument to ls().

Does your IDE perhaps capture stderr, only printing stdout? Or did you set up Panda to capture notify-output?

11

I am using Panda3D 1.10.4.1 64bit version.

12

I use IDLE and tried running your example, still no output. However, when executing the script with the command prompt, I got the output. Is there any way that I could make IDLE print the output?
Thanks for your help :slight_smile:

13

I use IDLE and as @serega-kkz mentioned, it seems to be an issue with the IDE. I did change anything in the Panda3D settings.

14

I tried to both print the function and just call the function. It seems, that is doesn’t matter what node I am trying, still no output. However, as @serega-kkz mentioned, it seems to be an issue with the IDE. I am using IDLE and as far as I know, I have not changed any of its printing settings.

15

May try.
from pprint import pprint
pprint (data)

16

That did not seem to work either. Perhaps I should just run the game from the command prompt whenever I want to print the node graph. Thanks for your help anyway :slight_smile: