3.5. Viewing tracks in 3-dimensions
3.5.1. 3D View
Lastly for the "viewing of plots", Debrief provides experimental support for viewing track files in 3D. However the tracks currently loaded must contain Depth information, and the correct libraries (Java3D) are installed on the machine.
Unfortunately there is not any 3-d data in the sample plots we've been using so far, but another sample file does. Close the current session, open a new, blank, one, and load the data-file named sen_tracks.rep. This is a datafile produced using ASSET, a simulator currently under development at PlanetMayo.
Once the tracks are loaded, you will see the view as below:
Now initialize the Tote by pressing Auto-Generate. Debrief now knows the time period covered by the tracks.
The updated 3D viewer in Debrief now shows 3-dimensional models of the exercise participants. The model used is taken from the SymbolType property of each track (although the default type is Submarine). So before opening the 3-d view, change the SymbolType of the Frigate track to Frigate. To do this, right-click on the track and select Frigate from the SymbolType drop-down list. Next press the "View in 3D" button 
to open the 3-d view winsow.
3.5.2. Initial View
A new window will open, containing a 3D view of the current track data, as shown below:
Enlarge the window until it covers about a quarter of your screen, then arrange the windows so that you can see both Debrief and the 3-d view..
3.5.3. Controlling the view
The view is controlled with the mouse using the following buttons:
Table 3-1. Mouse controls used in 3-D View
| Button | Operation |
|---|---|
| Rotate plot, effectively changing the current heading | |
| (or Alt--Left) | Zoom in and out of the view |
| Pan the plot around the view |
In addition to mouse-movement, controls have been added to the view to adjust the current view depth, heading, pan and zoom. Experiment with moving around the plot using these controls aswell as the mouse.
The drop-down list provided in the centre of the window provides a list of preset viewpoints. The Surface Look and Underwater Look viewpoints zoom out to the south of the centre of the plot, positioning the viewer either slightly above, or slightly below the water surface. The Top-Down viewpoint provides a god's-eye view of the data. Lastly are a series of viewpoints which each provide a "chase-plane" view of a particular participant. Thus it is possible to position yourself immediately above and behind a participant as it moves forward through an exercise serial.
Now, to return to the original view, select Surface Look from the drop-down list. Next rotate the heading to 270 degrees, take the depth down to -010, and zoom in to view the exercise from the stern of the submarine.
A set of properties are also provided to support the 3-d editing. The following properties are provided:
| Parameter | Description |
|---|---|
| Model Stretch | A scaling factor applied to the models, typically used for presenting broad overviews of a serial |
| Grid Delta | The spacing to use for the grid plotted on the surface |
| Show Coastline | Whether to plot a coastline on the sea surface (not yet implemented) |
| Show Drop Bars | Whether to show drop bars which stretch from a current vessel position vertically up or down to the sea surface, to assist in the spatial separation of vessels. |
| Show Foggy Ocean | Whether to shade the ocean surface |
| Show Sea Surface | Whether to plot a grid on the sea surface |
| Show Snail Trail | Whether to plot a snail-trail behind each vessel |
| Show Vessel Status | Whether to show a textual status string for each vessel |
| Snail Trail Length | The length (in time) of snail trail to plot for each vessel. |
3.5.4. Step through the serial
Now re-arrange the 3-d plot and the Debrief plot so you have a clear view of both, and move the time-stepper forward a single step. You will see each 3-d vessel representation move. As you move through the track using the button on the Time Stepper, note the highlights on the 3-D track moving. Now push the "Step Automatically" button, to make the plot step forward on its own, leaving us to play.
Whilst the plot is stepping forward, switch your attention back to the 3-d view. Experiment with using the 3 mouse buttons (or two plus the alt-key) and zoom in on the current point on the red-track. Learning to coordinate these three operations may seem difficult, but you'll soon pick it up.
The data-file we're using isn't all that interesting in this view, since neither participant reacts in response to a depth-change from the other. But, 3-d views of real exercise results can be particularly insightful, clearly illustrating a weapon losing contact of its target due to changing depth layer, or one target gaining detections of another as it moves into the same layer.
3.5.5. Close
Click on the close-button at the top-right of the 3-d view to close the panel.
3.5.6. Memory Leaks
The current version of the 3D libraries used in this viewer contains memory leaks. In general memory leaks are tidied up in each revision of Java-3d, so it is in your interest to try to keep up to date with the newest releases. [1]