AudioStreamPolyphonic with AudioStreamPlayer.pitch_scale

[razcore-rad]

Tested versions

v4.2.2.rc1.official [c7fb064]

System information

Ubuntu 23.10, Vulkan, NVIDIA GeForce RTX™ 2060 / NVIDIA GeForce RTX™ 2060

Issue description

Previously, in Godot 3 we could have the following setup with an AudioStreamPlayer where we could use pitch_scale with an Audio Clip track in the AnimationPlayer.

With Godot 4 this setup doesn't work any more because AudioStreamPolyphonic's pitch needs to be updated with AudioStreamPlaybackPolyphonic instance instead.

To make things worse, AudioStreamPlaybackPolyphonic is valid only after the AudioStreamPlayer.stream gets assigned so in the case above it's at the 1sec mark in the AnimationPlayer.

What should happen in my opinion is that AudioStreamPlayer.pitch_scale should auto-update the AudioStreamPlaybackPolyphonic pitch as well, otherwise it gets confusing because AudioStreamPolyphonic is the only one that behaves differntly, not being affected by the AudioStreamPlayer.pitch_scale value.

Steps to reproduce

1. Open the Minimal Reproduction Project.
2. Select the AnimationPlayer node.
3. Make sure dbg-audio-clips animation is selected from the dropdown list.
4. Play the animation and notice the Animation Clips: track pitch doesn't change.
5. Now select dbg-expected animation.
6. Play the animation and notice that this time the audio stream is properly pitch-shifted.

Minimal reproduction project (MRP)

godot-dbg.zip