How the Vision Set works
=========================================

Workspaces
----------------

The Vision Set uses a 2D camera to detect objects and calculate their
positions in space. This detection allows you to trigger the actions of your choice.

To allow such functions with a 2D camera, we developed a system
based on landmarks that define workspaces in 3 dimensions
(the third dimension being the height, taking the height of the landmarks as origin).

.. image:: ../images/workspace.png
         :alt: Workspace
         :width: 400px
         :align: center

For each action related to Vision, the camera will give you a relative position in
the workspace reference that the robot will translate to its own reference.

.. important::
    Please note that any action related to Vision will need to be done in a workspace, which means
    all 4 markers should be detectable by the camera

On the figure below, you can see an image from Ned's camera streaming with the
**Landmarks filter**. This filter makes sure that the robot is able to detect all 4
markers.

.. image:: ../images/debug_markers.jpg
         :alt: Workspace debug
         :height: 400px
         :align: center

.. note::
    The first landmark is slightly different from the others : it has
    only 3 blacks areas, which allows to sort the landmarks clockwise


Conditions
----------------

To use the Vision related functions, two conditions are required:
 - Workspace’s landmarks positions are set and mechanically fixed
 - The landmarks delimiting the workspace are visible

.. important::
    Please note that these two conditions need to be met to allow the Vision related operations.