trusty (3) al_create_bitmap.3alleg5.gz

NAME

       al_create_bitmap - Allegro 5 API

SYNOPSIS

              #include <allegro5/allegro.h>

              ALLEGRO_BITMAP *al_create_bitmap(int w, int h)

DESCRIPTION

       Creates  a new bitmap using the bitmap format and flags for the current thread.  Blitting between bitmaps
       of differing formats, or blitting between memory bitmaps and display bitmaps may be slow.

       Unless you set the ALLEGRO_MEMORY_BITMAP flag, the bitmap is created for the current  display.   Blitting
       to another display may be slow.

       If  a  display  bitmap  is  created,  there  may be limitations on the allowed dimensions.  For example a
       DirectX or OpenGL backend usually has a maximum allowed texture size - so if bitmap  creation  fails  for
       very  large  dimensions,  you  may  want  to re-try with a smaller bitmap.  Some platforms also dictate a
       minimum texture size, which is relevant if you plan to use this bitmap with the primitives addon.  If you
       try  to  create  a  bitmap  smaller  than this, this call will not fail but the returned bitmap will be a
       section of a larger bitmap with the minimum size.  The minimum size that will work on all platforms is 32
       by 32.

       Some  platforms  do not directly support display bitmaps whose dimensions are not powers of two.  Allegro
       handles this by creating a larger bitmap that has dimensions that are powers of two and then returning  a
       section  of  that bitmap with the dimensions you requested.  This can be relevant if you plan to use this
       bitmap with the primitives addon but shouldn't be an issue otherwise.

SEE ALSO

       al_set_new_bitmap_format(3alleg5),      al_set_new_bitmap_flags(3alleg5),       al_clone_bitmap(3alleg5),
       al_create_sub_bitmap(3alleg5), al_destroy_bitmap(3alleg5)