Cannot change order of 3D axes

[peterennis]

Description of bug / unexpected behavior

I want to rotate 3D so that X and Y are like 2D, with Z being out.
There is no "Out" option so I am left with the default.

This code has a work around for showing labels due to some
limitation of Cairo (per ChatGPT).

Expected behavior

Labels should rotate correctly.
Cannot add numbers in axes.
No "Out" option for Z.

How to reproduce the issue

Code for reproducing the problem

With Jupyter

%%manim -qm -v WARNING Label3DAxes

from manim import *

class Label3DAxes(ThreeDScene):
    def construct(self):
        # Set camera so XY plane is front-facing, Z comes out
        self.set_camera_orientation(phi=0 * DEGREES, theta=90 * DEGREES)

        # Create 3D axes
        axes = ThreeDAxes(
            x_range=[-3, 3, 1],
            y_range=[-3, 3, 1],
            z_range=[-3, 3, 1],
            x_length=6,
            y_length=6,
            z_length=6
        )
        self.add(axes)

        # Create MathTex labels
        x_label = MathTex("X").scale(1.2).move_to(axes.c2p(3.2, 0, 0))
        y_label = MathTex("Y").scale(1.2).move_to(axes.c2p(0, 3.2, 0))
        z_label = MathTex("Z").scale(1.2).move_to(axes.c2p(0, 0, 3.2))

        # Save original orientation to prevent spinning
        for label in [x_label, y_label, z_label]:
            label.save_state()

        def face_camera(label):
            label.restore()
            label.rotate(-self.camera.get_phi(), axis=RIGHT)
            label.rotate(-self.camera.get_theta(), axis=UP)

        for label in [x_label, y_label, z_label]:
            label.add_updater(face_camera)
            self.add(label)

        # Add a cube for spatial reference
        cube = Cube(side_length=2).move_to(axes.c2p(0, 0, 0))
        self.add(cube)

        # Rotate around Z axis (depth)
        self.begin_ambient_camera_rotation(rate=0.2, axis=OUT)
        self.wait(8)
        self.stop_ambient_camera_rotation()

Additional media files

Images/GIFs

Add the code to current Jupyter Notebook Examples

System specifications

System Details

• OS (Windows 11)
• RAM: 16 GB
• Python version Latest
• Installed modules

PASTE HERE

[peterennis]

WARNING!!!

The above user is new, and the link is reported as a virus.
Reported abuse to GitHub.

@behackl Please kill the above comment.

[uwezi]

If you want the X/Y axes to point the same way as in a 2D scene with Z facing out (i.e. towards the viewer) then why are you turning your camera around the theta-axis? That would be the default orientation of a 3D scene.

Also numbers in the axes can be added using the axes-configuration dictionaries or using .add_coordinates()

class Label3DAxes(ThreeDScene):
    def construct(self):
        # Set camera so XY plane is front-facing, Z comes out
        #self.set_camera_orientation(phi=0 * DEGREES, theta=90 * DEGREES)

        # Create 3D axes
        axes = ThreeDAxes(
            x_range=[-3, 3, 1],
            y_range=[-3, 3, 1],
            z_range=[-3, 3, 1],
            x_length=6,
            y_length=6,
            z_length=6
        ).add_coordinates()
        self.add(axes)

        # Create MathTex labels
        x_label = MathTex("X").scale(1.2).move_to(axes.c2p(3.2, 0, 0))
        y_label = MathTex("Y").scale(1.2).move_to(axes.c2p(0, 3.2, 0))
        z_label = MathTex("Z").scale(1.2).move_to(axes.c2p(0, 0, 3.2))

        # Save original orientation to prevent spinning
        for label in [x_label, y_label, z_label]:
            label.save_state()

        def face_camera(label):
            label.restore()
            label.rotate(-self.camera.get_phi(), axis=RIGHT)
            label.rotate(-self.camera.get_theta(), axis=UP)

        for label in [x_label, y_label, z_label]:
            label.add_updater(face_camera)
            self.add(label)

[uwezi]

For the rotation, the angle you are probably looking for would be gamma, the angle around the line-of-sight through the camera lens. This is not equal to the Z-axis of your scene, but neither are phi or theta what you might think they are: think of the camera as mounted on an earth globe, phi and theta are the angles of latitude and longitude respectively, with the camera looking down onto the globe, while gamma rotates the camera around its own line-of-sight.

A different, perhaps less confusing way to add rotation into a 3D scene is to keep your camera at a fixed position and rotate your objects instead - those rotations would then be aligned to the X, Y and Z axes of your scene.

class Label3DAxes(ThreeDScene):
    def construct(self):
        # Set camera so XY plane is front-facing, Z comes out
        #self.set_camera_orientation(phi=0 * DEGREES, theta=90 * DEGREES)

        # Create 3D axes
        axes = ThreeDAxes(
            x_range=[-3, 3, 1],
            y_range=[-3, 3, 1],
            z_range=[-3, 3, 1],
            x_length=6,
            y_length=6,
            z_length=6
        ).add_coordinates()
        self.add(axes)

        # Create MathTex labels
        x_label = MathTex("X").scale(1.2).move_to(axes.c2p(3.2, 0, 0))
        y_label = MathTex("Y").scale(1.2).move_to(axes.c2p(0, 3.2, 0))
        z_label = MathTex("Z").scale(1.2).move_to(axes.c2p(0, 0, 3.2))

        # Save original orientation to prevent spinning
        for label in [x_label, y_label, z_label]:
            label.save_state()

        def face_camera(label):
            label.restore()
            label.rotate(-self.camera.get_phi(), axis=RIGHT)
            label.rotate(-self.camera.get_theta(), axis=UP)

        for label in [x_label, y_label, z_label]:
            label.add_updater(face_camera)
            self.add(label)

        # Add a cube for spatial reference
        cube = Cube(side_length=2).move_to(axes.c2p(0, 0, 0))
        self.add(cube)

        # Rotate around Z axis (depth)
        self.begin_ambient_camera_rotation(rate=0.2, about="gamma")
        self.wait(8)
        self.stop_ambient_camera_rotation()

Label3DAxes.mp4

[peterennis]

@uwezi - The second one is what I was aiming for - 2D rotation that I can change to 3d later.

Your camera view explanation was very helpful. It will help avoid getting grit in my eyes the next time
I play around in my sandbox 😃

Thanks, 👍

[uwezi]

Your camera view explanation was very helpful. It will help avoid getting grit in my eyes the next time I play around in my sandbox 😃

see also here for the latitudes and longitudes: https://gist.github.com/uwezi/9634bd756ae3bfa57b404926c9fb93ea

[peterennis]

This code is the same you provided with axes coordinate changes:

# Magic for use in Jupyter Notebook
# %%manim -qm -v WARNING Label3DAxes

from manim import *

class Label3DAxes(ThreeDScene):
    def construct(self):
        # Set camera so XY plane is front-facing, Z comes out
        #self.set_camera_orientation(phi=0 * DEGREES, theta=90 * DEGREES)

        # Create 3D axes
        axes = ThreeDAxes(
            x_range=[-2.5, 2.5, 1],
            y_range=[-2.5, 2.5, 1],
            z_range=[-2.5, 2.5, 1],
            x_length=5,
            y_length=5,
            z_length=5
        ).add_coordinates()
        self.add(axes)

        # Create MathTex labels
        x_label = MathTex("X").scale(1.2).move_to(axes.c2p(2.75, 0, 0))
        y_label = MathTex("Y").scale(1.2).move_to(axes.c2p(0, 2.75, 0))
        z_label = MathTex("Z").scale(1.2).move_to(axes.c2p(0, 0, 2.75))

        # Save original orientation to prevent spinning
        for label in [x_label, y_label, z_label]:
            label.save_state()

        def face_camera(label):
            label.restore()
            label.rotate(-self.camera.get_phi(), axis=RIGHT)
            label.rotate(-self.camera.get_theta(), axis=UP)

        for label in [x_label, y_label, z_label]:
            label.add_updater(face_camera)
            self.add(label)

        # Add a cube for spatial reference
        cube = Cube(side_length=2).move_to(axes.c2p(0, 0, 0))
        self.add(cube)

        # Rotate around Z axis (depth)
        self.begin_ambient_camera_rotation(rate=0.2, about="gamma")
        self.wait(8)
        self.stop_ambient_camera_rotation()

but gives this result in Jupyter:

Labels are not shown.

[uwezi]

The labels are there - look to the very right of the formerly horizontal axis.

I did not look into your label orientation algorithm, but since the camera is now positioned differently with respect to theta and phi your previous code necessarily breaks.

Here is code which might give you a hint as how to orient things pointing to the camera:
https://gist.github.com/uwezi/94d389365ed315dd2b8eb0e2803e270d

Also I strongly suggest to continue this discussion on the Discord server, since an "issue" on github is probably not the best suited place: https://docs.manim.community/en/stable/faq/general.html#where-can-i-find-more-resources-for-learning-manim

[peterennis]

the following works:

%%manim -qm -v WARNING Label3DAxes
# Magic for use in Jupyter Notebook

from manim import *

class Label3DAxes(ThreeDScene):
    def construct(self):
        # Make XY plane like 2D: X right, Y up, Z out of screen:
        self.set_camera_orientation(phi=0 * DEGREES, theta=-90 * DEGREES)
        # phi = 0 → no tilt (we’re in the XY plane)
        # theta = -90° → rotates the camera so X points right, Y up, and Z comes out

        axes = ThreeDAxes(
            x_range=[-2, 2, 1],
            y_range=[-2, 2, 1],
            z_range=[-2, 2, 1],
            x_length=4, y_length=4, z_length=4
        ).add_coordinates()
        self.add(axes)

        # Labels placed just outside the axes ticks:
        x_label = MathTex("X").scale(1.2).move_to(axes.c2p(2.5, 0, 0))
        y_label = MathTex("Y").scale(1.2).move_to(axes.c2p(0, 2.5, 0))
        z_label = MathTex("Z").scale(1.2).move_to(axes.c2p(0, 0, 2.5))

        # Tell the 3D camera/scene to keep these mobjects with fixed orientation
        # (the right API for v0.19.0)
        self.add_fixed_orientation_mobjects(x_label, y_label, z_label)
        self.add(x_label, y_label, z_label)

        # Reference cube:
        cube = Cube(side_length=2).move_to(axes.c2p(0, 0, 0))
        self.add(cube)

        # Choose the rotation you want:
        # Rotate around Z axis (depth)
        self.begin_ambient_camera_rotation(rate=0.2, about='gamma')
        self.wait(8)
        self.stop_ambient_camera_rotation()

Thanks