I'm currently participating in SOCIS and I code for Marble. My task is to implement a usable image and panorama viewer based on the standards of the kml language. More precisely I work on the correct handling of the <PhotoOverlay> tag.
My plan is to follow the example of Google Earth, so I dropped out the old PhotoOverlay visualisation method of Marble (just drawing the image to the screen) and approached the problem from a different way.
A PhotoOverlay is marked with a clickable placemark which shows a little popup information dialog when you click on it now. It displays the preview of the image and some information which can be specified under a <PhotoOverlay> object like name, description and location.
Here are some screenshots:
I used the content of http://mars.jpl.nasa.gov to create the screenshots.
For next, I will improve this with actually opening the photo, and visualising it in Marble as a zoomable, pannable plain image.
To be continued...