fix: implement per-camera ground plane correction

py_workspace/aruco/ground_plane.py

@@ -51,7 +51,10 @@ class GroundPlaneMetrics:
     correction_applied: bool = False
     num_cameras_total: int = 0
     num_cameras_valid: int = 0
-    correction_transform: Mat44 = field(default_factory=lambda: np.eye(4))
+    # Per-camera corrections
+    camera_corrections: Dict[str, Mat44] = field(default_factory=dict)
+    skipped_cameras: List[str] = field(default_factory=list)
+    # Summary stats (optional, maybe average of corrections?)
     rotation_deg: float = 0.0
     translation_m: float = 0.0
     camera_planes: Dict[str, FloorPlane] = field(default_factory=dict)
@@ -354,7 +357,7 @@ def refine_ground_from_depth(
         metrics.message = f"Found {len(valid_planes)} valid planes, required {config.min_valid_cameras}"
         return extrinsics, metrics
 
-    # 3. Compute consensus
+    # 3. Compute consensus (for reporting/metrics only)
     try:
         consensus = compute_consensus_plane(valid_planes)
         metrics.consensus_plane = consensus
@@ -362,42 +365,55 @@ def refine_ground_from_depth(
         metrics.message = f"Consensus computation failed: {e}"
         return extrinsics, metrics
 
-    # 4. Compute correction
-    correction = compute_floor_correction(
-        consensus,
-        target_floor_y=config.target_y,
-        max_rotation_deg=config.max_rotation_deg,
-        max_translation_m=config.max_translation_m,
-    )
+    # 4. Compute and apply per-camera correction
+    new_extrinsics = extrinsics.copy()
 
-    metrics.correction_transform = correction.transform
-
-    if not correction.valid:
-        metrics.message = f"Correction invalid: {correction.reason}"
-        return extrinsics, metrics
-
-    # 5. Apply correction
-    # T_corr is the transform that moves the world frame.
-    # New world points P' = T_corr * P
-    # We want new extrinsics T'_world_cam such that P' = T'_world_cam * P_cam
-    # T'_world_cam * P_cam = T_corr * (T_world_cam * P_cam)
-    # So T'_world_cam = T_corr * T_world_cam
-
-    new_extrinsics = {}
-    T_corr = correction.transform
+    # Track max rotation/translation for summary metrics
+    max_rot = 0.0
+    max_trans = 0.0
+    corrections_count = 0
 
     for serial, T_old in extrinsics.items():
+        # If we didn't find a plane for this camera, skip it
+        if serial not in metrics.camera_planes:
+            metrics.skipped_cameras.append(serial)
+            continue
+
+        plane = metrics.camera_planes[serial]
+
+        correction = compute_floor_correction(
+            plane,
+            target_floor_y=config.target_y,
+            max_rotation_deg=config.max_rotation_deg,
+            max_translation_m=config.max_translation_m,
+        )
+
+        if not correction.valid:
+            metrics.skipped_cameras.append(serial)
+            continue
+
+        T_corr = correction.transform
+        metrics.camera_corrections[serial] = T_corr
+
+        # Apply correction: T_new = T_corr @ T_old
         new_extrinsics[serial] = T_corr @ T_old
 
-    # Calculate metrics
-    # Rotation angle of T_corr
-    trace = np.trace(T_corr[:3, :3])
-    cos_angle = np.clip((trace - 1) / 2, -1.0, 1.0)
-    metrics.rotation_deg = float(np.rad2deg(np.arccos(cos_angle)))
-    metrics.translation_m = float(np.linalg.norm(T_corr[:3, 3]))
+        # Update summary metrics
+        trace = np.trace(T_corr[:3, :3])
+        cos_angle = np.clip((trace - 1) / 2, -1.0, 1.0)
+        rot_deg = float(np.rad2deg(np.arccos(cos_angle)))
+        trans_m = float(np.linalg.norm(T_corr[:3, 3]))
 
+        max_rot = max(max_rot, rot_deg)
+        max_trans = max(max_trans, trans_m)
+        corrections_count += 1
+
+    metrics.rotation_deg = max_rot
+    metrics.translation_m = max_trans
     metrics.success = True
-    metrics.correction_applied = True
-    metrics.message = "Success"
+    metrics.correction_applied = corrections_count > 0
+    metrics.message = (
+        f"Corrected {corrections_count} cameras, skipped {len(metrics.skipped_cameras)}"
+    )
 
     return new_extrinsics, metrics