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al_set_new_display_option(3)                      al_set_new_display_option(3)

NAME
       al_set_new_display_option - Allegro 5 API

SYNOPSIS

              #include <allegro5/allegro.h>

              void al_set_new_display_option(int option, int value, int importance)

DESCRIPTION
       Set an extra display option, to be used when creating new displays on
       the calling thread.  Display options differ from display flags, and
       specify some details of the context to be created within the window
       itself.  These mainly have no effect on Allegro itself, but you may
       want to specify them, for example if you want to use multisampling.

       The 'importance' parameter can be either:

       o ALLEGRO_REQUIRE - The display will not be created if the setting can
         not be met.

       o ALLEGRO_SUGGEST - If the setting is not available, the display will
         be created anyway.  FIXME: We need a way to query the settings back
         from a created display.

       o ALLEGRO_DONTCARE - If you added a display option with one of the
         above two settings before, it will be removed again.  Else this does
         nothing.

       The supported options are:

       ALLEGRO_COLOR_SIZE
              This can be used to ask for a specific bit depth.  For example
              to force a 16-bit framebuffer set this to 16.

       ALLEGRO_RED_SIZE, ALLEGRO_GREEN_SIZE, ALLEGRO_BLUE_SIZE,
       ALLEGRO_ALPHA_SIZE
              Individual color component size in bits.

       ALLEGRO_RED_SHIFT, ALLEGRO_GREEN_SHIFT, ALLEGRO_BLUE_SHIFT,
       ALLEGRO_ALPHA_SHIFT
              Together with the previous settings these can be used to specify
              the exact pixel layout the display should use.  Normally there
              is no reason to use these.

       ALLEGRO_ACC_RED_SIZE, ALLEGRO_ACC_GREEN_SIZE, ALLEGRO_ACC_BLUE_SIZE,
       ALLEGRO_ACC_ALPHA_SIZE
              This can be used to define the required accumulation buffer
              size.

       ALLEGRO_STEREO
              Whether the display is a stereo display.

       ALLEGRO_AUX_BUFFERS
              Number of auxiliary buffers the display should have.

       ALLEGRO_DEPTH_SIZE
              How many depth buffer (z-buffer) bits to use.

       ALLEGRO_STENCIL_SIZE
              How many bits to use for the stencil buffer.

       ALLEGRO_SAMPLE_BUFFERS
              Whether to use multisampling (1) or not (0).

       ALLEGRO_SAMPLES
              If the above is 1, the number of samples to use per pixel.  Else
              0.

       ALLEGRO_RENDER_METHOD:
              0 if hardware acceleration is not used with this display.

       ALLEGRO_FLOAT_COLOR
              Whether to use floating point color components.

       ALLEGRO_FLOAT_DEPTH
              Whether to use a floating point depth buffer.

       ALLEGRO_SINGLE_BUFFER
              Whether the display uses a single buffer (1) or another update
              method (0).

       ALLEGRO_SWAP_METHOD
              If the above is 0, this is set to 1 to indicate the display is
              using a copying method to make the next buffer in the flip chain
              available, or to 2 to indicate a flipping or other method.

       ALLEGRO_COMPATIBLE_DISPLAY
              Indicates if Allegro's graphics functions can use this display.
              If you request a display not useable by Allegro, you can still
              use for example OpenGL to draw graphics.

       ALLEGRO_UPDATE_DISPLAY_REGION
              Set to 1 if the display is capable of updating just a region,
              and 0 if calling al_update_display_region(3) is equivalent to
              al_flip_display(3).

       ALLEGRO_VSYNC
              Set to 1 to tell the driver to wait for vsync in
              al_flip_display(3), or to 2 to force vsync off.  The default of
              0 means that Allegro does not try to modify the vsync behavior
              so it may be on or off.  Note that even in the case of 1 or 2 it
              is possible to override the vsync behavior in the graphics
              driver so you should not rely on it.

       ALLEGRO_MAX_BITMAP_SIZE
              When queried this returns the maximum size (width as well as
              height) a bitmap can have for this display.  Calls to
              al_create_bitmap(3) or al_load_bitmap(3) for bitmaps larger than
              this size will fail.  It does not apply to memory bitmaps which
              always can have arbitrary size (but are slow for drawing).

       ALLEGRO_SUPPORT_NPOT_BITMAP
              Set to 1 if textures used for bitmaps on this display can have a
              size which is not a power of two.  This is mostly useful if you
              use Allegro to load textures as otherwise only power-of-two
              textures will be used internally as bitmap storage.

       ALLEGRO_CAN_DRAW_INTO_BITMAP
              Set to 1 if you can use al_set_target_bitmap(3) on bitmaps of
              this display to draw into them.  If this is not the case
              software emulation will be used when drawing into display
              bitmaps (which can be very slow).

       ALLEGRO_SUPPORT_SEPARATE_ALPHA
              This is set to 1 if the al_set_separate_blender(3) function is
              supported.  Otherwise the alpha parameters will be ignored.

SEE ALSO
       al_set_new_display_flags(3)

Allegro reference manual                          al_set_new_display_option(3)