gfx_mode_select_filter

gfx_mode_select_filter(3alleg4)  Allegro manual  gfx_mode_select_filter(3alleg4)



NAME
       gfx_mode_select_filter - Even more extended version of the graphics mode
       selection dialog. Allegro game programming library.

SYNOPSIS
       #include <allegro.h>


       int gfx_mode_select_filter(int *card, int *w, int *h, int *color_depth,
       int (*filter)(int, int, int, int));

DESCRIPTION
       Even more extended version of the graphics mode selection dialog, which
       allows the programmer to customize the contents of the dialog and the
       user to select the color depth as well as the resolution and hardware
       driver.  `filter' will be passed (card, w, h, color_depth) quadruplets
       and must return 0 to let the specified quadruplet be added to the list of
       displayed modes.

       As with gfx_mode_select, the values stored at the addresses passed to the
       function will be used as suggestions for the initial selections in the
       dialog, defaulting to the first entry in each list if the values are not
       found. Initialize the data stored at the addresses passed to the function
       to the value of 0 or -1 if you want to ensure that the initial selection
       for each list will be the first entry.

       If the dialog is OK'd, it stores the selections at the addresses passed
       to the function.

       Example usage :

          ret = gfx_mode_select_filter(&card, &w, &h, &color_depth, user_filter);
          if (ret) {/* User okayed dialog or user_filter removed all modes */
             if (card == GFX_NONE) {
                // No modes available
                *card = 0;/* Make sure not to leave *card == GFX_NONE */
                return -1;
             }
             /* Handle changing to new mode here... */

          } else {/* User cancelled dialog or there was an error (unlikely) */
             if (card == GFX_NONE) {
                /* Error, probably out of memory */
                *card = 0;/* Make sure not to leave *card == GFX_NONE */
                return -2;
             }
             /* Carry on in current graphics mode if that is acceptable */
          }


RETURN VALUE
       Returns zero if the user cancelled the dialog or an error occurred. In
       the case of an error then *card is assigned the value GFX_NONE. The
       functions return non-zero if the user made a selection OR if all the
       modes were filtered out. In the case that all of the modes were filtered
       out, then *card is assigned the value GFX_NONE. This means you should NOT
       initialize the *card to the value of GFX_NONE, as it could interfere with
       determining the proper return value.


SEE ALSO
       gfx_mode_select(3alleg4), gfx_mode_select_ex(3alleg4),
       set_color_depth(3alleg4), set_gfx_mode(3alleg4), gui_fg_color(3alleg4)



Allegro                           version 4.4.3  gfx_mode_select_filter(3alleg4)