Keyword: rdraw
Pressing this button will redraw the main window, and any sub-windows that are showing the same display mode (electrical or physical). The drawing window with keyboard focus can also be redrawn by typing Ctrl-r. Clicking with button 2 near the center of the window is yet another way to force a redraw. After most operations, the windows are automatically redrawn, so forcing a redraw is not often needed. Exceptions are when changing layer colors and fill patterns.