Download Squidy - A Zoomable Design Environment for Natural User Interfaces

49
4.3. DATAFLOW PROGRAMMING
1. Start: Starts the implemented algorithm of a node, allocates required processing
resources and activates the node as ready for processing.
2. Stop: Stops the algorithm, tears down any allocated resources and sets the node
status as not processing.
3. Delete: Deletes a node from the pipeline and frees all previously allocated resources.
4. Duplicate: Duplicates a node by copying all of its properties, which then is an
equal clone besides it is a distinct object instance.
5. Publish: Publishes the node and all of its properties to a common repository of
nodes. All users of Squidy have access to this repository and thus can use such
published nodes.
6. Update: If a node is originating from the repository this action updates this node
to a recent version.
(a)
(b)
Figure 4.10: A node, e.g. a node to control Powerpoint presentations reveals its actions on
mouse over: (a) The Powerpointer node with the mouse cursor besides the node,
(b) the Powerpointer node with the mouse cursor over the node and the four essential actions start processing, stop processing, duplicate node, delete node (counterclockwise starting from the top left).
In order to not overwhelm the user with unnecessary options, these actions are only provided on mouse over at the zoomed out state of a node. In addition to not overloading
the user interface, only four actions are provided at a glance (see Figure 4.10 (b)). For
instance, a node to control Powerpoint presentations reveals its essential actions on mouse
over. These actions correspond to actions 1-4 in counter-clockwise order starting from top
left. How the actions 5 and 6 can be executed will be described in the next paragraphs.
The zoomed in state of a node reveals a navigation bar, which is providing additional
information related to the node. This navigation bar is located at the top of a node and
provides actions, node naming, and a navigation breadcrumb at a glance (compare Figure 4.9 and Figure 4.11). Furthermore, the actions enumerated previously are altogether
visible in the order 1-6 starting from the left.