Is there a way of rendering an asset as invisible to the camera but visible to the bproc.writer.write_coco_annotations? about blenderproc

[cornerfarmer]

Hey @lolitsjoey,

sorry for the late response. You could perform some kind of raycasts and check which rays hit the object, similar to https://github.com/DLR-RM/BlenderProc/blob/main/blenderproc/python/camera/CameraValidation.py#L158. With that information you could calculate the bounding box.
Alternatively, you could also sample points on the object surface and project it into the camera plane via bproc.camera.project_points. However, this will not consider for the object being hidden behind other objects.