Probabilistic Forecasting Exploratory Development

Legend Overlay and Management

New Legend Related KeyBoard Controls Cheat Sheet

Within AWIPS, legends have been used quite successfully as a user interface device for manipulating the characteristics of overlays. However, anyone familiar with current D2D ensemble capabilities will realize that if several ensemble fields are loaded, legend management becomes very difficult. So one of the goals of this prototyping was to improve that.

Remember that when dealing with keyboard shortcuts, one always needs to give the D2D keyboard focus, not just for these new controls.

Step 1: Start D2D.
Step 2: From Volume->Browser..., load Sources Ensemble->SREF-21, Fields Wind->WindSpeed, and Planes Misc->Surface (see below, click on image for full resolution). Minimize the VB.

Step 3: Click on the D2D title bar to get keyboard focus and hit the > key a few times, note the density increases (see below, click on image for full resolution).

Step 4: Now hit the < key a few times, note the density decreases. Adjust the density so some but not many contours are visible.

The main reason this capability was added is that sometimes the automated density reduction can be too aggressive.

Step 5: Expand the Legend by clicking Mouse Button-1 (MB1) on the + at the left side of the Legend.
Step 6: Toggle one group of items in the Legend off and on with Mouse Button-2 (MB2). Note the focus marker "O" is now only on the left side of the items in that group (see below, click on image for full resolution).

Step 7: Use the < and > keys on the keyboard, note that only the items in focus change density.

The point here is that the < and > keys always respond to Legend focus.

Step 8: Expand the Legend, if not already expanded. Hit the + key on the main keyboard (not on the KeyPad). Note that this toggles the first item in the Legend (from the bottom) off. Continue to hit the + key, note that this rotates the toggle state upward through the Legend stack.
Step 9: Now hit the - key a few times, note that this rotates the toggle state downward.
Step 10: Toggle all items in the Legend off with Mouse Button-3 (MB3).
Step 11: Now toggle one group of items on with MB2. Then use the + and - keys on the keyboard to rotate the toggle state upward by group through the Legend stack.

The point is that if one starts with the toggle state completely segregated by group, the +/- keys will automatically alter their behavior to account for that.

Step 12: Clear the screen.
Step 13: Exit D2D.