macOS 27 Beta: 3D View does not reliably render updated Solid/Joint transformations and may enter No Rendering

[shuminzxr]

Describe the Bug

On macOS 27 Beta, Webots R2025a can run simulations and update the internal scene state, but the 3D View does not always visually reflect updated Solid/Joint transformations. In some cases, the viewport also switches to a black screen with the message No Rendering.

This appears to be a rendering/viewport issue rather than a controller or physics issue.

Observed behavior

In my own world:

• The Python controller runs normally.
• CSV logging works.
• Vehicle motion is simulated correctly.
• HingeJointParameters.position changes over time.
• The corresponding endPoint Solid.rotation also changes.
• Arm joint sensor values and logged joint angles change normally.
• However, the visible arm geometry does not visually update as expected in the 3D View.

I also observed rendering instability in Webots sample worlds. The 3D View can enter a No Rendering state.

Why I think this is a rendering issue

The simulation state appears to be updating correctly:

• Joint parameters update in the Scene Tree.
• End-point Solid rotation values update.
• Controller output and CSV data are consistent with joint motion.
• The issue is mainly that the 3D viewport does not reliably display these updates.

This suggests the problem may be in the 3D View / WREN / OpenGL rendering layer rather than in the controller API or joint simulation.

Steps to Reproduce

1. Run Webots R2025a on macOS 27 Beta.
2. Open a world with a moving joint or Solid.
3. Run the simulation.
4. Observe that HingeJointParameters.position and endPoint Solid.rotation can update in the Scene Tree.
5. Observe that the visible geometry may not update correctly in the 3D View.
6. In some cases, the viewport enters No Rendering.

Expected behavior

The 3D View should visually reflect updated Solid and Joint transformations in real time.

System

• Webots version: R2025a
• OS: macOS 27 Beta
• Hardware: Apple Silicon M1 Max
• Build: locally rebuilt/patched Webots from source
• Related issue: macOS 27 Beta: Webots R2025a falsely detects all TCP ports as already in use #6976

Additional context

This may be related to macOS 27 graphics/Qt/OpenGL/WREN compatibility. I previously observed terminal messages such as:

GLD_TEXTURE_INDEX_2D is unloadable and bound to sampler type (Float)

I can provide more logs or test additional sample worlds if useful.