[AD] X hardware cursors fix

[Peter Wang <tjaden@xxxxxxxxxx>]

Without the attached patch, the if the first cursor shown was:

- MOUSE_CURSOR_ALLEGRO: then choose a system cursor later would do nothing

- something else: then MOUSE_CURSOR_ALLEGRO would not be hardware 
accelerated

Also attached is the start of an example program, which demonstrates the 
bug.

Peter

Index: src/x/xwin.c
===================================================================
RCS file: /cvsroot/alleg/allegro/src/x/xwin.c,v
retrieving revision 1.87
diff -u -p -r1.87 xwin.c
--- src/x/xwin.c	19 Mar 2005 11:15:07 -0000	1.87
+++ src/x/xwin.c	19 Mar 2005 13:35:09 -0000
@@ -331,6 +331,18 @@ static void _xwin_hide_x_mouse(void)
    XGCValues gcvalues;
    Pixmap pixmap;
 
+   XUndefineCursor(_xwin.display, _xwin.window);
+
+   if (_xwin.cursor != None) {
+      XFreeCursor(_xwin.display, _xwin.cursor);
+      _xwin.cursor = None;
+   }
+
+   if (_xwin.xcursor_image != None) {
+      XcursorImageDestroy(_xwin.xcursor_image);
+      _xwin.xcursor_image = None;
+   }
+
    pixmap = XCreatePixmap(_xwin.display, _xwin.window, 1, 1, 1);
    if (pixmap != None) {
       GC temp_gc;

/*
 * Test program for hardware cursors.
 */

#include <stdio.h>
#include <allegro.h>

static void handle_key(int *quit);
static void do_select_cursor(int cursor);

int main(void)
{
   int quit;
   
   allegro_init();
   install_timer();
   install_mouse();
   install_keyboard();
   if (set_gfx_mode(GFX_AUTODETECT, 640, 480, 0, 0) != 0) {
      set_gfx_mode(GFX_TEXT, 0, 0, 0, 0);
      allegro_message("Error setting video mode: %s\n", allegro_error);
      return 1;
   }
   else {
      printf("gfx_driver: %s\n", gfx_driver->name);
      fflush(stdout);
   }
   enable_hardware_cursor();

   // first cursor shown
   do_select_cursor(MOUSE_CURSOR_ALLEGRO);

   quit = FALSE;
   while (!quit) {
      handle_key(&quit);
      rest(1);
   }
   
   return 0;
}
   
END_OF_MAIN()

static void handle_key(int *quit)
{
   int k;

   if (!keypressed())
      return;

   k = readkey() & 0xff;

   switch (k) {
      case 27:
      case 'q':
      case 'Q':
	 (*quit) = TRUE;
	 break;
      case '1':
	 do_select_cursor(MOUSE_CURSOR_ALLEGRO);
	 break;
      case '2':
	 do_select_cursor(MOUSE_CURSOR_ARROW);
	 break;
      case '3':
	 do_select_cursor(MOUSE_CURSOR_BUSY);
	 break;
      case '4':
	 do_select_cursor(MOUSE_CURSOR_QUESTION);
	 break;
      case '5':
	 do_select_cursor(MOUSE_CURSOR_EDIT);
	 break;
      default:
	 break;
   }
}

static void do_select_cursor(int cursor)
{
   printf("----\n");
   printf("before: %s, %s\n", 
      (gfx_capabilities & GFX_HW_CURSOR) ? "HW_CURSOR" : "no HW_CURSOR",
      (gfx_capabilities & GFX_SYSTEM_CURSOR) ? "SYSTEM_CURSOR" : "no SYSTEM_CURSOR");

   select_mouse_cursor(cursor);
   show_mouse(screen);

   printf("after: %s, %s\n", 
      (gfx_capabilities & GFX_HW_CURSOR) ? "HW_CURSOR" : "no HW_CURSOR",
      (gfx_capabilities & GFX_SYSTEM_CURSOR) ? "SYSTEM_CURSOR" : "no SYSTEM_CURSOR");

   fflush(stdout);
}