The outermost layer shown is a cylinder representing the solenoid. The initial scenegraph is prepared by opening the Objy database and reading the tracker layer geometry. The event data branch is then attached to the detector branch, and compiled. When a new event is selected, the previous event branch is detached and deleted. The whole scenegraph can be rotated, translated and zoomed using the mouse.
All objects are pickable.
The JavaCMS event viewer allows the user to remove or add all the subdetector detail piecewise, to rotate and zoom the picture, and will eventually allow the user to select individual objects in the display and interrogate the Object Database for their properties. A 2D applet was initially developed, an image of which appears below. The Electromagnetic Calorimeter crystal tower energies are shown in yellow, with reconstructed energy clusters in red. Some comments on the use of Java with Objectivity, and other views of the 2D applet are available here .