More work on SDL events. Also fixed an issue (very old?) where Grafx2 didn't accurately follow mouse movements when it's very busy, ie when using Continuous Freehand with a large brush or transparency. Now, as long as the setting Merge mouse is zero, all intermediate mouse positions are correctly buffered and played back. From my testing, up to 7 seconds will be memorized.

git-svn-id: svn://pulkomandy.tk/GrafX2/trunk@1568 416bcca6-2ee7-4201-b75f-2eb2f807beb1

src/graph.c

@@ -1082,6 +1082,7 @@ void Fill_general(byte fill_color)
     if (! (Permanent_draw_count&7))
     {
       Uint32 now = SDL_GetTicks();
+      SDL_PumpEvents();
       if (now>= Permanent_draw_next_refresh)
       {
         Permanent_draw_next_refresh = now+100;