1Passive objects 2=============== 3 4Besides physical interaction and perception via cameras or depth sensors, 5passive objects in a simulation can be interacted with in several other ways. 6 7For instance some objects can be set to be graspable by a robot (or a human), 8and specific sensors like the :doc:`Semantic camera <../sensors/semantic_camera>` 9may provide extended information about a particular object, such as its type. 10 11Creating passive objects 12------------------------ 13 14Passive objects are either plain, regular Blender objects, or a group 15of objects. 16 17 18.. image:: ../../../media/object_grouping.png 19 :align: center 20 21In the screenshot above (from 22``$MORSE/share/morse/data/props/objects.blend``), the ``RollingChair`` 23hierarchy is made up of an empty object (the ``RollingChair`` itself) and 24five child objects (four for the bounding box, one for the actual mesh). 25 26Since all these six Blender objects share the same prefix, they will be 27correctly imported together when using the MORSE Builder API. 28 29When imported manually (from the Blender user interface), this eases the selection 30of relevant objects. 31 32.. note:: 33 34 You can also have a look at the tips on adding a :doc:`bounding box around your objects 35 <../tips/bounding_boxes>`. 36 37For complex objects with non-trivial bounding-boxes, we recommend the 38creation of groups (which also has performance advantages, through 39*group instances*). To do this: 40 41#. Select all the objects that you want to group 42#. **make sure they are properly centered on the Blender origin** 43#. Press :kbd:`Ctrl+G` to create a new group (they should appear in green in 44 the viewport) 45#. In the outliner, select the *Groups* view. You can double-click on the group 46 name to change it. 47 48Passive objects properties 49-------------------------- 50 51To be set as an **interactive** passive object, you only have to add the (Game) 52property ``Object`` to the object, and to set this as boolean property 53with the value ``True``. 54 55Other, **optional**, properties allow us to control other features of the object: 56 57- ``Label`` (``String``): the name (or label) of the object [#]_, 58- ``Description`` (``String``): a longer description of the object [#]_, 59- ``Type`` (``String``): the type of the object [#]_, 60- ``Graspable`` (``Boolean``): if the object is graspable or not [#]_. 61 62You can temporarly disable an object by simply setting its ``Object`` property to ``False``. 63 64.. [#] Used to display the object name in :doc:`human's manipulation mode <human>` 65 and by the semantic camera sensor as ID of tracked objects. 66.. [#] Not used yet. 67.. [#] Used by the semantic camera sensor, defaults to ``Object``. 68.. [#] Used by the human's manipulation mode and the :doc:`gripper <../actuators/gripper>` 69 actuators. 70 71.. note:: 72 73 For the manipulation routines to work, the above properties (especially, ``Graspable``) 74 must be set on the **object holding the mesh you want to grab**. 75 76Importing passive objects with the MORSE Builder API 77---------------------------------------------------- 78 79Passive objects can easily get added to a scenario defined with the 80:doc:`MORSE Builder API <../../user/builder>`. 81 82The following example imports the ``SmallTable`` Blender object from the 83``props/objects.blend`` assets file, set some properties, and places it 84in the scene: 85 86.. code-block:: python 87 88 from morse.builder import * 89 90 table = PassiveObject('props/objects', 'SmallTable') 91 table.setgraspable() 92 table.translate(x=3.5, y=-3, z=0) 93 table.rotate(z=0.2) 94 95As with any other property, the game properties can be set using the following method: 96 97.. code-block:: python 98 99 table.properties(Object = True, Graspable = False, Label = "TABLE") 100 101.. warning:: 102 To set an object to be graspable, you **must** also call the ``setgraspable(..)`` function. 103 It adds an internal collision sensor to the object, required for pick and place 104 actions with the human avatar. 105 106 107The next example shows how to add semi-randomly placed chairs in a 108scene: 109 110.. code-block:: python 111 112 import random 113 from morse.builder import * 114 115 # Add some randomly placed chairs 116 for i in range(3): 117 chair = PassiveObject('props/objects', 'RollingChair') 118 chair.translate(x=random.uniform(1.5, 7.0), 119 y=random.uniform(-5.0, 0.0), 120 z=0.0000) 121 chair.rotate(z=random.uniform(0.0, 6.2)) # rotation in radians 122 123Combining passive objects with switches 124--------------------------------------- 125 126It is possible to create portable devices by combining switches with 127a passive object. The creation of such devices will be explained in 128terms of a flashlight. 129 130First of all we need to create the mesh of our flashlight. After that 131create the switch as a seperate object and make it a child of the mesh. Next 132add a lamp object and again, make it a child of the mesh. Name all these 133objects so that they all share the same prefix. 134Now all that's left is defining the single objects for the use with Morse. 135So use the :doc:`Morse Utils <../addons/morse_utils>` Addon to define the 136switch. Add the Logic for the lamp using the ``Morse Light`` preset. 137Disable the physics for the switch with the ``Ghost`` option in the Physics 138Properties, so that there can't be collisions with the mesh. 139 140You can now import the flashlight using the :doc:`MORSE Builder API <../../user/builder>` 141as explained above. You can also import it manually and set the mesh to be 142a passive object using the ``Morse Utils``. 143 144.. warning:: 145 If you use :doc:`compound bounding boxes <../tips/bounding_boxes>` do not use the ``Compound`` 146 option on the switch object. Also do not make it a ``No Collision`` 147 object or otherwise you can't use the switch. 148 149The switch works exactly the same as a static one. Use the ``Left Mouse Button`` 150to turn the device on and off. This also works while the object is carried. 151
