Segfault when highlighting/selecting cols/rows near the bottom in fullscreen SDL about pdcurses

[Bill-Gray]

I've a two-monitor system. Both are 1920x1080, but one is in portrait mode.

I could replicate this crash on the landscape-mode screen, where the bottom line is 'partial' (the screen height is not an even multiple of the font height). I couldn't replicate it on the portrait-mode screen, where there is no partial bottom line. It affected rain and other demos.

The problem arises because SDLn gets a mouse event in the partial line and (in this case) we're highlighting, say, the 42nd line on a screen with only 41 "full" lines. We just need to ignore mouse events in the partial line area (or in partial columns, should such arise).

I never noticed this before because for non-fullscreen windows, there are no partial rows or columns.

The patch I've made for PDCursesMod will need some minor modifications for PDCurses, but not much. Haven't checked yet to see if this affects X11 or (for PDCursesMod) WinGUI or DOSVGA.