on_surface_object_sampling

Object selection and manipulation

The focus of this example is the OnSurfaceSampler which allows pose sampling for some selected objects on top of a selected surface.

Usage

Execute this in the BlenderProc main directory:

python run.py examples/on_surface_object_sampling/config.yaml examples/on_surface_object_sampling/camera_positions examples/on_surface_object_sampling/scene.blend examples/on_surface_object_sampling/output

• examples/on_surface_object_sampling/config.yaml: path to the configuration file with pipeline configuration.
• examples/on_surface_object_sampling/camera_positions: text file with parameters of camera positions.
• examples/on_surface_object_sampling/scene.blend: path to the object file with the basic scene.
• examples/on_surface_object_sampling/output: path to the output directory.

Visualization

Visualize the generated data:

python scripts/visHdf5Files.py examples/on_surface_object_sampling/output/0.hdf5

Steps

• Loads all objects from scene.blend: loader.BlendLoader module.
• Set selected objects as active: manipulators.EntityManipulator module.
• Set selected objects as passive: manipulators.EntityManipulator module.
• Sample selected object poses on top a selected surface: object.OnSurfaceSampler module.
• Runs the physics simulation: object.PhysicsPositioning module.
• Creates a point light: lighting.LightLoader module.
• Sets two camera positions: camera.CameraLoader module.
• Renders rgb: renderer.RgbRenderer module.
• Writes the output to .hdf5 containers: writer.Hdf5Writer module.

Config file

OnSurfaceSampler

{
  "module": "object.OnSurfaceSampler",
  "config": {
    "objects_to_sample": {                      # mesh objects to sample on the surface
      "provider": "getter.Entity",
      "conditions": {
        "name": ".*phere.*"                     # we select all UV spheres and Icospheres
      }
    },
    "surface": {                                # the object to use as a surface to sample on
      "provider": "getter.Entity",              
      "index": 0,                               # make sure the Provider returns only one object
      "conditions": {
        "name": "Cube"                          # Cube in the scene is selected
      }
    },
    "pos_sampler": {
      "provider": "sampler.UpperRegionSampler",
      "to_sample_on": {                         # select it again, but inside the sampler to define the upper region the space above the Cube
        "provider": "getter.Entity",
        "index": 0,                             # returns only the first object to satisfy the conditions
        "conditions": {
          "name": "Cube"                        # same Cube is selected
        }
      },
      "min_height": 1,                          # points sampled in this space will have height varying in this min-max range
      "max_height": 4,                          # this range also helps the module to satisfy the non-intersecting bounding boxes checks for the sampled objects and the surface faster
      "use_ray_trace_check": False,
    },
    "min_distance": 0.1,                        # minimal distance between sampled objects
    "max_distance": 10,                         # and a maximal distance. The smaller the min-max range, the more tries the module can take to sample the appropriate location
    "rot_sampler": {                            # uniformly sample rotation
      "provider": "sampler.Uniform3d",
      "max": [0,0,0],
      "min": [6.28,6.28,6.28]
    }
  }
},

• invoke a getter.Entity Provider to select objects_to_sample - objects we want to sample poses for.
• invoke a getter.Entity Provider to select an object to use as a surface to sample on top (note "index": 0 which ensures that Provider returns only one object.)
• sample positions for objects_to_sample via sampler.UpperRegionSampler (configure min_height and max_height such that sampled objects don't intersect with the surface).
• min_distance and max_distance define an acceptable range between sampled objects. The smaller the range, the more max_iterations (default is 100) may be required to successfully place an object.
• sample rotation for objects_to_sample using sampler.Uniform3d Provider.

More examples

• object_pose_sampling: Simple object pose sampling object inside simple volume.
• physics_positioning: More on physics simulation.