Graphic Display Evolution

The GTVIRT graphic library works (and works fast), but is not fully satisfactory. Its maintenance is difficult, the use of the plot hierarchy not straightforward, color support not clear, etc...

To simplify it, it was suggested to drop off old code supporting old peculiar devices. However, the multi-protocol aspect of the library was considered as essential. It could allow ultimately to display in Java for example. We should also keep the DEVICE TEKTRO X for slow links. The following short term improvements were mentionned:

• Addition of ``Expandable rectangular box'' dragged by mouse.
• Addition of ``Expandable vector'' dragged by mouse
• Addition of ``Mouse defined polygon''. This would be faster and simpler than the current ways of defining polygons.
• Addition of ``Mouse defined region'', basically limited by the screen resolution. This would essentially be a large polygon with corners defined by the screen resolution.
• Better support for 24-bit or 32-bit colour display should
• Re-writing of the GTVIRT to use multi-thread programming to separate window display from internal plot handling. This would allow resizing and refresh events to be handled much more conveniently. SIC events (as mentionned before) would be practicle in this respect.

Evolutions in GreG would be nil or very limited, e.g. a zoomed box (by opposition to a zoom window) could be easily implemented once the ``Expandable rectangular box'' is available in the GTVIRT.

A. Perrigouard declared to be interested by these subjects. A proper description of the GTVIRT library concepts (goals ?) would be required to get started (Stephane Guilloteau ?).