Update app.py

app.py

@@ -190,17 +190,28 @@ def get_seed(randomize_seed: bool, seed: int) -> int:
 # --- Camera & Rotation Helpers ---
 
 def get_look_at_matrix(eye, target, up):
-    """Calculate a Look-At rotation matrix."""
-    z_axis = eye - target
-    z_axis = z_axis / np.linalg.norm(z_axis)
+    """
+    Calculate a Look-At rotation matrix.
+    Returns a matrix for a camera looking at 'target' from 'eye'
+    with a 'Right-Down-Forward' (RDF) coordinate system, which is standard
+    for Rerun pinholes when no axis prefix is specified.
+    """
+    # Forward vector (Z) points from eye to target
+    forward = target - eye
+    forward = forward / np.linalg.norm(forward)
     
-    x_axis = np.cross(up, z_axis)
-    x_axis = x_axis / np.linalg.norm(x_axis)
+    # Right vector (X) is perpendicular to Up and Forward
+    right = np.cross(forward, up) # Note: cross order matters
+    if np.linalg.norm(right) < 1e-6:
+        # Handle degenerate case where forward ~= up
+        right = np.array([1.0, 0.0, 0.0])
+    right = right / np.linalg.norm(right)
     
-    y_axis = np.cross(z_axis, x_axis)
+    # Down vector (Y) is perpendicular to Forward and Right
+    down = np.cross(forward, right)
     
-    # Create rotation matrix (3x3)
-    rotation_matrix = np.column_stack([x_axis, y_axis, z_axis])
+    # Rerun expects columns [X, Y, Z]
+    rotation_matrix = np.column_stack([right, down, forward])
     return rotation_matrix
 
 def log_turntable_camera(rec, radius=2.0, height=0.5, num_frames=180):
@@ -210,10 +221,10 @@ def log_turntable_camera(rec, radius=2.0, height=0.5, num_frames=180):
     try:
         rec.log("/", rr.ViewCoordinates.RIGHT_HAND_Y_UP, static=True)
     except Exception:
-        pass # Ignore if ViewCoordinates fails
+        pass 
 
     center = np.array([0.0, 0.0, 0.0])
-    up_world = np.array([0.0, 1.0, 0.0]) # Y-up
+    up_world = np.array([0.0, 1.0, 0.0]) # World Up
 
     for i in range(num_frames):
         # Robust Time Setting with Fallback
@@ -222,7 +233,6 @@ def log_turntable_camera(rec, radius=2.0, height=0.5, num_frames=180):
         elif hasattr(rec, "set_time_seconds"):
             rec.set_time_seconds("sim_time", i * 0.1)
         else:
-            # If no time setting method exists, animation is impossible.
             raise AttributeError("RecordingStream lacks set_time_sequence or set_time_seconds")
         
         # Calculate angle
@@ -235,7 +245,7 @@ def log_turntable_camera(rec, radius=2.0, height=0.5, num_frames=180):
         
         eye = np.array([cam_x, cam_y, cam_z])
         
-        # Get rotation to look at center
+        # Get rotation (RDF)
         rot_mat = get_look_at_matrix(eye, center, up_world)
         
         # Log Camera Transform (Extrinsics)
@@ -248,12 +258,12 @@ def log_turntable_camera(rec, radius=2.0, height=0.5, num_frames=180):
         )
         
         # Log Camera Intrinsics (Pinhole)
+        # Removed unsupported 'camera_axis_prefix'
         rec.log(
             "world/camera",
             rr.Pinhole(
                 fov_y=math.radians(45),
                 aspect_ratio=1.0,
-                camera_axis_prefix="RUB", 
             )
         )
 
@@ -434,9 +444,10 @@ def generate_3d(
                 rr.Transform3D(translation=eye, mat3x3=get_look_at_matrix(eye, center, up)),
                 static=True
             )
+            # Removed unsupported 'camera_axis_prefix'
             rec.log(
                 "world/camera",
-                rr.Pinhole(fov_y=math.radians(45), aspect_ratio=1.0, camera_axis_prefix="RUB"),
+                rr.Pinhole(fov_y=math.radians(45), aspect_ratio=1.0),
                 static=True
             )