Add option to have cameras sorted inside the Birdseye stream (#5450)

* Add option to sort cameras inside Birdseye

* Make default order to be sorted alphabetically

* Add docs for sorting cameras

* Update index.md for cameras

* Remove irelevant comments

frigate/config.py

@@ -396,6 +396,7 @@ class BirdseyeConfig(FrigateBaseModel):
 # uses BaseModel because some global attributes are not available at the camera level
 class BirdseyeCameraConfig(BaseModel):
     enabled: bool = Field(default=True, title="Enable birdseye view for camera.")
+    order: int = Field(default=0, title="Position of the camera in the birdseye view.")
     mode: BirdseyeModeEnum = Field(
         default=BirdseyeModeEnum.objects, title="Tracking mode for camera."
     )

frigate/output.py

@@ -4,6 +4,7 @@ import logging
 import math
 import multiprocessing as mp
 import os
+import operator
 import queue
 import signal
 import subprocess as sp
@@ -292,8 +293,16 @@ class BirdsEyeFrameManager:
         # calculate layout dimensions
         layout_dim = math.ceil(math.sqrt(len(active_cameras)))
 
+        # check if we need to reset the layout because there are new cameras to add
+        reset_layout = (
+            True if len(active_cameras.difference(self.active_cameras)) > 0 else False
+        )
+
         # reset the layout if it needs to be different
-        if layout_dim != self.layout_dim:
+        if layout_dim != self.layout_dim or reset_layout:
+            if reset_layout:
+                logger.debug(f"Added new cameras, resetting layout...")
+
             logger.debug(f"Changing layout size from {self.layout_dim} to {layout_dim}")
             self.layout_dim = layout_dim
 
@@ -327,6 +336,20 @@ class BirdsEyeFrameManager:
 
         self.active_cameras = active_cameras
 
+        # this also converts added_cameras from a set to a list since we need
+        # to pop elements in order
+        added_cameras = sorted(
+            added_cameras,
+            # sort cameras by order and by name if the order is the same
+            key=lambda added_camera: (
+                self.config.cameras[added_camera].birdseye.order,
+                added_camera,
+            ),
+            # we're popping out elements from the end, so this needs to be reverse
+            # as we want the last element to be the first
+            reverse=True,
+        )
+
         # update each position in the layout
         for position, camera in enumerate(self.camera_layout, start=0):
             # if this camera was removed, replace it or clear it