Loading and manipulating objects

November 23, 2023 ยท View on GitHub

Downloading assets

If don't have any data yet, BlenderProc offers download functionality for many datasets and freely available assets via the blenderproc CLI:

  • blenderproc download blenderkit <output_dir>: Downloads materials and models from blenderkit
  • blenderproc download cc_textures <output_dir>: Downloads textures from cc0textures.com.
  • blenderproc download haven <output_dir>: Downloads HDRIs, Textures and Models from polyhaven.com.
  • blenderproc download ikea <output_dir>: Downloads the IKEA dataset. (At the moment this dataset is not availabe! Use pix3d instead, as ikea is a subset of pix3D)
  • blenderproc download pix3d <output_dir>: Downloads the Pix3D dataset.
  • blenderproc download scenenet <output_dir>: Downloads the scenenet dataset.
  • blenderproc download matterport3d <output_dir>: Downloads the Matterport3D dataset.

Loading

BlenderProc provides various ways of importing your 3D models. All loaders can be accessed via the bproc.loader.load_* methods, which all return the list of loaded MeshObjects.

objs = bproc.loader.load_obj("mymesh.obj")

Filetype-specific loaders:

  • bproc.loader.load_obj: Loading .obj and .ply files.
  • bproc.loader.load_blend: Loading from .blend files.

Dataset-specific loaders:

  • bproc.loader.load_AMASS: Loads objects from the AMASS Dataset.
  • bproc.loader.load_bop_objs: Loads the 3D models of any BOP dataset and allows replicating BOP scenes.
  • bproc.loader.load_bop_scene: Loads any real BOP scenes using 3D models.
  • bproc.loader.load_bop_intrinsics: Loads intrinsics of specified BOP dataset.
  • bproc.loader.load_front3d: Loads 3D-Front scenes.
  • bproc.loader.load_ikea: Loads objects from the IKEA dataset.
  • bproc.loader.load_pix3d: Loads Pix3D objects.
  • bproc.loader.load_replica: Loads scenes from the Replica dataset.
  • bproc.loader.load_scenenet: Loads SceneNet scenes.
  • bproc.loader.load_shapenet: Loads objects from the ShapeNet dataset.
  • bproc.loader.load_suncg: Loads SUNCG scenes.
  • bproc.loader.load_matterport3d: Loads a Matterport3D scene.

Manipulating objects

As mentioned above, the loaders return a list of MeshObjects. Each of these objects can be manipulated in various ways:

Changing poses

Changing the location of an object can be done via:

obj.set_location([2, 0, 1])

Setting the rotation via euler angles:

obj.set_rotation_euler([np.pi, 0, 0])

Or setting the full pose via the 4x4 local-to-world transformation matrix:

obj.set_local2world_mat(tmat)

Or applying a 4x4 transformation matrix on the current pose:

obj.apply_T(tmat)

Custom properties

If you have any user-specific attributes that you want to assign to objects, you should use custom properties. In a key-value like fashion you can assign any desired value to a given object.

This is how you set a custom property:

obj.set_cp("my_prop", 42)

And that is how you retrieve one:

obj.get_cp("my_prop")

More information

For more information look at the reference manual of MeshObject.

Next tutorial: Configuring the camera