I have identified a specific performance bottleneck related to the Navigation Display (ND) rendering logic. The simulator experiences significant stutters and frame time spikes when moving the camera while the ND is active in certain configurations.
Reproduction Steps:
1. Load the A346 at a heavy airport (e.g., KSFO).
2. Create and initialize a long-haul flight plan in the MCDU (e.g., KSFO to VHHH).
3. Set the ND mode to PLAN.
4. Set the ND Range Selector to 10.
5. Move the camera (panning/rotating) inside or outside the cockpit.
Result: Heavy stutters and noticeable FPS drops.
6. Change the ND Range Selector to 40 or higher.
Result: The stutters disappear, and the camera movement becomes smooth again.
7. Turn the ND display OFF (using the brightness/power knob) at any Range setting.
Result: All stutters disappear instantly, confirming the issue is strictly related to display rendering.
Observed Behavior:
The stutters are directly tied to the ND rendering high-density vector data at low range scales (10nm). The performance hit is only present when the ND has to redraw the flight plan path during camera movement. This suggests a MainThread/RdrThread bottleneck in the display's drawing logic rather than a system simulation (FMGC) issue.
Expected Behavior:
ND rendering should be optimized (ideally via GPU acceleration) to prevent blocking the MainThread, regardless of the selected Range or camera movement.
By
Anatoliy ·
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