Multi-image cursor tracking information; DD 'registration'
Showing a cursor tracking box for each DD registered on the display panel is moderately high on the 'To-do' list. A simpler tracking box was implemented for the alpha release which tracks only the first-registered image. The label on the track box identifies the image being tracked.
Users should beware of this, since the _last_-registered raster image is usually the one that's visible. New users are often confused by the difference between an 'open' DD (a drawing layer or DisplayData (DD) exists for the image) and 'registered' (the DD is set to draw on a panel). When you select an image and push the 'Raster' button, a DD is both open and registered. You can have more than one Display Panel window (soon), and an existing DD can be registered on all, some or none of them. An Options panel tab will exist for all open DDs, even if the DD is not set to draw (registered) on any panel at the moment.
The [un]register button is the one with two overlapping squares. Users are advised/encouraged to (manually) unregister an old raster DD when another one is opened on top of it (or completely close the old DD, if done with it). This assures that the new image displays and that its tracking information is shown.
Leaving more than one raster registered is usually only useful with the animator in 'blink' mode; in that case each image must have the same coordinates (such as clean and dirty images of the same field), and the animator will display the successive images when stepped. In the animator's normal mode (channel animation), a raster and contour can often be usefully registered simultaneously, but not two rasters.
In future I would like to add some automatic assistance in unregistering 'invisible' rasters. (In the far future I hope to add transparent layering of rasters).
- 02 Nov 2006