Remove obsolete implementation and simplify project structure

src/anyimage/server/geometry/projection.py

@@ -0,0 +1,31 @@
+def unproject_depth_frame(depth, intrinsics, extrinsics):
+    import numpy as np
+
+    height, width = depth.shape
+    x, y = np.meshgrid(
+        np.arange(width, dtype=np.float32),
+        np.arange(height, dtype=np.float32),
+    )
+    pixels = np.stack((x, y, np.ones_like(x)), axis=-1).reshape(-1, 3)
+    rays = (np.linalg.inv(intrinsics) @ pixels.T).T
+    camera_points = rays * depth.reshape(-1, 1)
+    camera_points = np.column_stack(
+        (camera_points, np.ones(camera_points.shape[0], dtype=np.float32))
+    )
+    world_to_camera = np.eye(4, dtype=np.float32)
+    world_to_camera[: extrinsics.shape[0], :4] = extrinsics
+    world_points = (np.linalg.inv(world_to_camera) @ camera_points.T).T
+    return world_points[:, :3].reshape(height, width, 3)
+
+
+def unproject_camera_depth(depth, intrinsics):
+    import numpy as np
+
+    height, width = depth.shape
+    x, y = np.meshgrid(
+        np.arange(width, dtype=np.float32),
+        np.arange(height, dtype=np.float32),
+    )
+    pixels = np.stack((x, y, np.ones_like(x)), axis=-1).reshape(-1, 3)
+    rays = (np.linalg.inv(intrinsics) @ pixels.T).T
+    return (rays * depth.reshape(-1, 1)).reshape(height, width, 3)