What design pattern?
I was referring to whether the Preview design should follow Infovis reference model, which is a general specification for re-usable visualization toolkit design:
Raw Data -> Data Tables -> Visual Structures -> Views
My initial understanding to the preview module is that it is in a form close to the common visualization model like specified above, which is also implemented by Prefuse.
From specification, we begin by having a number of visual items including nodes, edges, lables, mini-labels and convex-hull. A more detailed description on design for Preview module starting from data io to display is: (we use the name in model to refer to different components):
1. We start from processing raw data which is objects (node and edge, etc) from Gephi graph. The builders should be responsible reading the information stored in objects and storing them to data tables, which is supported by various type and data structures. Meanwhile, create visual items that corresponds to each information record stored in the data table.
2. We use properties to describe the visual structure of visual items, most of which would share common characteristics such as colors, borders, opacity, distortion, enabling, etc. Some type of visual items such as convex-hull uses polygon to specify how smooth it can be. We will also need environment/global properties to specify overall quality of the layout such as anti-aliasing, etc.
3. At last, the renderer will interpret properties associated in each visual item and export them to specified output: PApplet, PDF, SVG, etc. We may allow query or control of some form to search and highlight certain visual items in the display (eg, filtering nodes in PApplet or highlight filtered nodes in generated Vector Graph).
Each component from above are independent from each other and thus can be easily extended. I will give more thoughts to the item specification and implementation.
