# Copyright 2018 The dm_control Authors.

#

# Licensed under the Apache License, Version 2.0 (the "License");

# you may not use this file except in compliance with the License.

# You may obtain a copy of the License at

#

# http://www.apache.org/licenses/LICENSE-2.0

#

# Unless required by applicable law or agreed to in writing, software

# distributed under the License is distributed on an "AS IS" BASIS,

# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

# See the License for the specific language governing permissions and

# limitations under the License.

# ============================================================================

"""Tools for adding custom cameras to the arena."""

import collections

from dm_control.composer.observation import observable

CameraSpec = collections.namedtuple('CameraSpec', ['name', 'pos', 'xyaxes'])

# Custom cameras that may be added to the arena for particular tasks.

FRONT_CLOSE = CameraSpec(

name='front_close',

pos=(0., -0.6, 0.75),

xyaxes=(1., 0., 0., 0., 0.7, 0.75)

)

FRONT_FAR = CameraSpec(

name='front_far',

pos=(0., -0.8, 1.),

xyaxes=(1., 0., 0., 0., 0.7, 0.75)

)

TOP_DOWN = CameraSpec(

name='top_down',

pos=(0., 0., 2.5),

xyaxes=(1., 0., 0., 0., 1., 0.)

)

LEFT_CLOSE = CameraSpec(

name='left_close',

pos=(-0.6, 0., 0.75),

xyaxes=(0., -1., 0., 0.7, 0., 0.75)

)

RIGHT_CLOSE = CameraSpec(

name='right_close',

pos=(0.6, 0., 0.75),

xyaxes=(0., 1., 0., -0.7, 0., 0.75)

)

def add_camera_observables(entity, obs_settings, *camera_specs):

"""Adds cameras to an entity's worldbody and configures observables for them.

Args:

entity: A `composer.Entity`.

obs_settings: An `observations.ObservationSettings` instance.

*camera_specs: Instances of `CameraSpec`.

Returns:

A `collections.OrderedDict` keyed on camera names, containing pre-configured

`observable.MJCFCamera` instances.

"""

obs_dict = collections.OrderedDict()

for spec in camera_specs:

camera = entity.mjcf_model.worldbody.add('camera', **spec._asdict())

obs = observable.MJCFCamera(camera)

obs.configure(**obs_settings.camera._asdict())

obs_dict[spec.name] = obs

return obs_dict