3.5. Saving and re-opening plots

3.5. Saving and re-opening plots
	Chapter 3. Manipulating track data

3.5.1. Save
3.5.2. Adding more data to a plot

3.5.1. Save

You may (or my not) know what the Replay file format used to load data into Debrief looked like. Whilst it is compact and easy to use, unfortunately the Replay file format does not allow us to store all of the formatting we have applied to the Debrief plot, nor the coordinates of what you are currently viewing, nor how you have arranged to store your data in layers. This problem is overcome by the use of the Debrief Plot-File format, an application defined using XML (see XML). Have a quick read about XML in the Reference Guide or Glossary if you're not aware of it and are sufficiently interested, otherwise, here's an overview:

Debrief stores plots in XML format with a custom DPF suffix
XML stands for eXstensible Markup Language, which allows structured data to be stored in text format, and is a world-wide standard promoted by http://www.w3c.org.
XML files can be edited outside Debrief, allowing you to cut and paste between plot-files to build up a new Plot-File, all in a text editor

Whilst a plot is typically created from an REP file, it may not be saved back into that REP file - it must be saved as a Debrief Plot-File ( DPF).

To save your work as a DPF file, click on the Save button: on the Workbench toolbar (or via the File menu). A file dialog will open (see below), allowing you to save the current session in this format.

	Note
	Debrief will only let you save the new plot into one of your project folders, so you must both select a folder and a provide a filename for the new file. Usefully, Debrief guesses that you probably want to name the plot the same as the REP file first loaded, but you can change this as required.

Figure 3.20. Save-file dialog

Save-as functionality is provided through the Save As button, next to the Save button in the File menu.

Debrief plot files can grow very large, and on occasion the memory required for the save operation can reach the upper limit provided to the application by default. When Debrief fails during the Save operation due to reaching the upper memory limit it stops trying to save to file and shows a message dialog advising you to increase the limit:“Ran out of memory whilst saving plot, try adding -Xmx256m to the command line”. This extra parameter passed when Debrief is starting instructs your PC to provide Debrief with 256 Megabytes of memory. If you continue to receive the error message try increasing the memory allocation to 512 Megabytes.

The save operation itself is conducted in a two-stage process. If the operation entails saving over an existing file (when you just do a plain Save, or Save As over-writing an older version) Debrief first writes the plot to a subtly different filename in the same directory (plot.dpf would get saved to ~plot.tmp). If the save operation completes successfully then the older file is deleted and the temporary file renamed to the originally requested filename. Thus, your existing file only gets overwritten on successful completion of the save.

3.5.2. Adding more data to a plot

With a plot already open, you are able to drag a Debrief DPF or REP file into its chart, adding the content to the existing session. Dragging multiple files onto the plot area adds them all to the existing session. To create a composite plot like this, you can start by using Debrief's New Plot Wizard (see relevant Cheat Sheet, Tutorials)


3.4. Layer management		3.6. Lightweight tracks