ALLEGRO_STATE(3)

NAME

ALLEGRO_STATE - Allegro 5 API

SYNOPSIS

    typedef struct ALLEGRO_STATE ALLEGRO_STATE;

DESCRIPTION

Opaque type which is passed to al_store_state(3)/al_restore_state(3).

The various state kept internally by Allegro can be displayed like this:

      global
          active system driver
              current config
      per thread
          new bitmap params
          new display params
          active file interface
          errno
          current blending mode
          current display
              deferred drawing
          current target bitmap
              current transformation
              current projection transformation
              current clipping rectangle
              bitmap locking
              current shader

In general, the only real global state is the active system driver. All other global state is per-thread, so if your application has multiple separate threads they never will interfere with each other. (Except if there are objects accessed by multiple threads of course. Usually you want to minimize that though and for the remaining cases use synchronization primitives described in the threads section or events described in the events section to control inter-thread communication.)