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al_create_bitmap(3)                                        al_create_bitmap(3)

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

Allegro reference manual                                   al_create_bitmap(3)