[Feat] add camera

examples/camera_movement.py

@@ -0,0 +1,51 @@
+import numpy as np
+
+import bsr
+
+
+def main(filename: str = "camera_movement"):
+
+    frame_rate = 60
+    total_time = 5
+
+    camera_heigh = 1.0
+    camera_radius = 1.0
+
+    bsr.clear_mesh_objects()
+
+    bsr.camera_manager.look_at = np.array([0.0, 0.0, 0.0])
+
+    for k, angle in enumerate(
+        np.linspace(0.0, 360.0, frame_rate * total_time + 1)
+    ):
+        bsr.camera_manager.location = np.array(
+            [
+                camera_radius * np.cos(np.radians(angle)),
+                camera_radius * np.sin(np.radians(angle)),
+                camera_heigh,
+            ]
+        )
+        bsr.camera_manager.set_keyframe(k)
+        bsr.frame_manager.update()
+
+    # Set the final keyframe number
+    bsr.frame_manager.set_frame_end()
+
+    # Set the frame rate
+    bsr.frame_manager.set_frame_rate(fps=frame_rate)
+
+    # Set the view distance
+    bsr.set_view_distance(distance=5)
+
+    # Deslect all objects
+    bsr.deselect_all()
+
+    # Select the camera object
+    bsr.camera_manager.select()
+
+    # Save as .blend file
+    bsr.save(filename + ".blend")
+
+
+if __name__ == "__main__":
+    main()

src/bsr/__init__.py

@@ -13,8 +13,8 @@
     clear_mesh_objects,
     deselect_all,
     scene_update,
-    select_camera,
 )
+from .camera import CameraManager
 from .frame import FrameManager
 from .geometry.composite.rod import Rod
 from .geometry.composite.stack import RodStack, create_rod_collection
@@ -30,4 +30,5 @@ def get_version() -> str:
 
 
 version: Final[str] = get_version()
+camera_manager = CameraManager()
 frame_manager = FrameManager()

src/bsr/blender_commands/macros.py

@@ -29,8 +29,3 @@ def clear_materials() -> None:
 def deselect_all() -> None:
     # Deselect all objects
     bpy.ops.object.select_all(action="DESELECT")
-
-
-def select_camera() -> None:
-    # Select the camera object
-    bpy.context.view_layer.objects.active = bpy.data.objects["Camera"]

src/bsr/camera.py

@@ -0,0 +1,171 @@
+from typing import Optional
+
+import bpy
+import numpy as np
+
+from bsr.tools.keyframe_mixin import KeyFrameControlMixin
+
+
+class CameraManager(KeyFrameControlMixin):
+    """
+    This class provides methods for manipulating the camera of the scene.
+    Only one instance exist, which you can access by: bsr.camera_manager.
+    """
+
+    def __init__(self, name: str = "Camera") -> None:
+        """
+        Constructor for camera manager.
+        """
+        self.name = name
+        self.__look_at_location: Optional[np.ndarray] = None
+        self.__sky = np.array([0.0, 0.0, 1.0])
+
+    @property
+    def camera(self) -> bpy.types.Object:
+        """
+        Return the camera object.
+        """
+        return bpy.data.objects[self.name]
+
+    def select(self) -> None:
+        """
+        Select the camera object.
+        """
+        bpy.context.view_layer.objects.active = self.camera
+
+    def set_keyframe(self, keyframe: int) -> None:
+        """
+        Sets a keyframe at the given frame.
+
+        Parameters
+        ----------
+        keyframe : int
+        """
+        self.camera.keyframe_insert(data_path="location", frame=keyframe)
+        self.camera.keyframe_insert(data_path="rotation_euler", frame=keyframe)
+
+    def set_film_transparent(self, transparent: bool = True) -> None:
+        """
+        Set the film transparency for rendering.
+
+        Parameters
+        ----------
+        transparent : bool, optional
+            Whether the film should be transparent. Default is True.
+        """
+        bpy.context.scene.render.film_transparent = transparent
+
+    @property
+    def is_film_transparent(self) -> bool:
+        """
+        Check if the film is set to transparent.
+
+        Returns
+        -------
+        bool
+            True if the film is transparent, False otherwise.
+        """
+        film_transparent: bool = bpy.context.scene.render.film_transparent
+        return film_transparent
+
+    @property
+    def location(self) -> np.ndarray:
+        """
+        Return the current location of the camera.
+        """
+        return np.array(self.camera.location)
+
+    @location.setter
+    def location(self, location: np.ndarray) -> None:
+        """
+        Set the location of the camera. If the look at location is set, the camera will be rotated to look at that location.
+
+        Parameters
+        ----------
+        location : np.array
+            The location of the camera.
+        """
+        assert isinstance(
+            location, np.ndarray
+        ), "location must be a numpy array"
+        assert len(location) == 3, "location must have 3 elements"
+        self.camera.location = location
+        if self.__look_at_location is not None:
+            self.camera.matrix_world = self.compute_matrix_world(
+                location=self.location,
+                direction=self.__look_at_location - self.location,
+                sky=self.__sky,
+            )
+
+    @property
+    def look_at(self) -> Optional[np.ndarray]:
+        """
+        Return the location the camera is looking at.
+        """
+        return self.__look_at_location
+
+    @look_at.setter
+    def look_at(self, location: np.ndarray) -> None:
+        """
+        Set the direction the camera is looking at.
+
+        Parameters
+        ----------
+        location : np.array
+            The direction the camera is looking at.
+        """
+        assert isinstance(
+            location, np.ndarray
+        ), "location must be a numpy array"
+        assert len(location) == 3, "location must have 3 elements"
+        assert (
+            np.allclose(self.location, location) == False
+        ), "camera and look at location must be different"
+
+        self.__look_at_location = location
+        self.camera.matrix_world = self.compute_matrix_world(
+            location=self.location,
+            direction=self.__look_at_location - self.location,
+            sky=self.__sky,
+        )
+
+    @staticmethod
+    def compute_matrix_world(
+        location: np.ndarray, direction: np.ndarray, sky: np.ndarray
+    ) -> np.ndarray:
+        """
+        Compute the world matrix of the camera.
+
+        Parameters
+        ----------
+        location : np.array
+            The location of the camera.
+        direction : np.array
+            The direction the camera is looking at.
+        sky : np.array
+            The sky direction of the camera. (unit vector)
+
+        Returns
+        -------
+        np.array
+            The world matrix of the camera.
+        """
+        assert isinstance(
+            location, np.ndarray
+        ), "location must be a numpy array"
+        assert len(location) == 3, "location must have 3 elements"
+        assert isinstance(
+            direction, np.ndarray
+        ), "direction must be a numpy array"
+        assert len(direction) == 3, "direction must have 3 elements"
+        assert isinstance(sky, np.ndarray), "sky must be a numpy array"
+        assert len(sky) == 3, "sky must have 3 elements"
+        assert np.linalg.norm(sky) == 1, "sky must be a unit vector"
+
+        direction = direction / np.linalg.norm(direction)
+        right = np.cross(direction, sky)
+        up = np.cross(right, direction)
+
+        return np.array(
+            [[*right, 0.0], [*up, 0.0], [*(-direction), 0.0], [*location, 1.0]]
+        )