Redesign motion capture plugin as Camera device type

Plugin now registers a "Camera" option in the Add Device dialog on load
(removes it on unload) instead of auto-creating a single device.

- camera_panel.py (new): CameraPanel with CameraScanThread that probes
  OpenCV indices 0–5, lists found cameras with resolution, shows
  "No cameras detected" when none available, simulation checkbox.
  build_device() returns CameraDevice for the selected index.

- device.py: rewrite MotionCaptureDevice → CameraDevice. Each instance
  owns its own CameraTracker created in connect(). Status is CONNECTED
  or SIMULATED based on tracker.simulated. get_config_widget() shows
  source/status and an "Open Camera View" button that launches the
  existing MotionCaptureWindow for that device's tracker. Backward-compat
  alias MotionCaptureDevice = CameraDevice kept for saved profiles.

- plugin.py: simplified to on_load/_PANELS registration + pixel_to_mm
  filter. No auto-devices, no toolbar button, no settings widget.

Camera data flows through the standard Device → Signal → Channel → Plot
pipeline like any other device.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 96 insertions, 28 deletions

diff --git a/plugins/motion_capture/device.py b/plugins/motion_capture/device.py
index f0d082c..9806030 100644
--- a/plugins/motion_capture/device.py
+++ b/plugins/motion_capture/device.py
@@ -1,34 +1,39 @@
 """
 motion_capture/device.py
 
-BaseDevice that reads x/y position from CameraTracker.
+BaseDevice implementation for a camera-based motion tracker.
+
+Each CameraDevice owns a CameraTracker that runs its own background
+capture thread.  connect() opens the camera; disconnect() releases it.
 
 Channels:
     x_pos  — horizontal position [px]   (left=0, right=frame_width)
     y_pos  — vertical position   [px]   (top=0, bottom=frame_height)
 
-Apply the  pixel_to_mm  filter in Signals → Channels to convert to mm.
+Apply the pixel_to_mm filter in Signals → Channels to convert to mm.
 """
 
 from __future__ import annotations
 
-import threading
-from typing import Any, Dict
+from typing import Any, Dict, Optional
 
 from devices.base_device import (
     BaseDevice, ChannelConfig, DeviceInfo, DeviceStatus,
 )
 
 
-class MotionCaptureDevice(BaseDevice):
+class CameraDevice(BaseDevice):
 
-    def __init__(self, tracker, device_id: str = "motion_capture"):
+    def __init__(self, device_id: str = "cam_0",
+                 camera_index: int = 0,
+                 simulate: bool = False):
+        name = "Camera (Sim)" if simulate else f"Camera {camera_index}"
         super().__init__(DeviceInfo(
             device_id   = device_id,
-            name        = "Motion Capture",
-            device_type = "virtual",
+            name        = name,
+            device_type = "camera",
             description = "Camera point-tracking — x/y position in pixels.",
-            icon        = "🎥",
+            icon        = "📷",
             channels    = [
                 ChannelConfig(
                     channel_id = "x_pos",
@@ -48,38 +53,101 @@ class MotionCaptureDevice(BaseDevice):
                 ),
             ],
         ))
-        self._tracker = tracker
-        self._lock    = threading.Lock()
-        self._last    = (0.0, 0.0)
+        self._camera_index           = camera_index
+        self._simulate               = simulate
+        self._tracker: Optional[Any] = None
+        self._tracking_win           = None
 
-    # ── BaseDevice interface ──────────────────────────────────────────────
+    # ── BaseDevice ────────────────────────────────────────────────────────
 
     def connect(self) -> bool:
-        self.status = DeviceStatus.SIMULATED
+        from tracker import CameraTracker
+        self._tracker = CameraTracker()
+        self._tracker.start(-1 if self._simulate else self._camera_index)
+        if self._tracker.simulated:
+            self.status = DeviceStatus.SIMULATED
+        else:
+            self.status = DeviceStatus.CONNECTED
         return True
 
     def disconnect(self) -> None:
+        if self._tracking_win is not None:
+            self._tracking_win.close()
+            self._tracking_win = None
+        if self._tracker is not None:
+            self._tracker.stop()
+            self._tracker = None
         self.status = DeviceStatus.DISCONNECTED
 
     def read_channels(self) -> Dict[str, float]:
+        if self._tracker is None:
+            return {"x_pos": 0.0, "y_pos": 0.0}
         pos = self._tracker.get_position()
-        if pos is not None:
-            with self._lock:
-                self._last = pos
-        with self._lock:
-            x, y = self._last
-        return {"x_pos": x, "y_pos": y}
+        if pos is None:
+            return {"x_pos": 0.0, "y_pos": 0.0}
+        x, y = pos
+        return {"x_pos": float(x), "y_pos": float(y)}
 
     def write_channel(self, channel_id: str, value: Any) -> bool:
         return False
 
     def get_config_widget(self):
-        from PyQt6.QtWidgets import QLabel
-        lbl = QLabel(
-            "Configure via the Motion Capture toolbar window.\n\n"
-            "Apply 'pixel_to_mm' filter in Signals → Channels\n"
-            "to convert pixel coordinates to millimetres."
+        from PyQt6.QtWidgets import (
+            QFormLayout, QLabel, QPushButton, QVBoxLayout, QWidget,
+        )
+
+        w = QWidget()
+        lay = QVBoxLayout(w)
+        lay.setContentsMargins(8, 8, 8, 8)
+        lay.setSpacing(10)
+
+        form = QFormLayout()
+        form.setContentsMargins(0, 0, 0, 0)
+
+        src_lbl = QLabel(
+            "Simulation" if self._simulate else f"Camera {self._camera_index}"
+        )
+        src_lbl.setObjectName("traceSource")
+        form.addRow("Source:", src_lbl)
+
+        self._status_lbl = QLabel(self.status.name.title())
+        self._status_lbl.setObjectName("traceSource")
+        form.addRow("Status:", self._status_lbl)
+
+        lay.addLayout(form)
+
+        open_btn = QPushButton("🎥  Open Camera View")
+        open_btn.setObjectName("addTraceBtn")
+        open_btn.clicked.connect(self._open_tracking_window)
+        lay.addWidget(open_btn)
+
+        hint = QLabel(
+            "In the Camera View: click the frame to set the tracking\n"
+            "point. Apply the 'pixel_to_mm' filter in Signals → Channels\n"
+            "to convert pixel coordinates to real-world units."
         )
-        lbl.setObjectName("traceSource")
-        lbl.setWordWrap(True)
-        return lbl
+        hint.setObjectName("traceSource")
+        hint.setWordWrap(True)
+        lay.addWidget(hint)
+        lay.addStretch()
+
+        return w
+
+    # ── Internal ──────────────────────────────────────────────────────────
+
+    def _open_tracking_window(self):
+        if self._tracker is None:
+            return
+        from window import MotionCaptureWindow
+        if self._tracking_win is None:
+            self._tracking_win = MotionCaptureWindow(self._tracker)
+            self._tracking_win.closed.connect(self._on_tracking_win_closed)
+        self._tracking_win.show()
+        self._tracking_win.raise_()
+
+    def _on_tracking_win_closed(self):
+        self._tracking_win = None
+
+
+# Backward-compat alias for any profiles that reference the old class name
+MotionCaptureDevice = CameraDevice