al_use_transform - Allegro 5 API

       Sets  the  transformation  to  be  used  for the the drawing operations on the target bitmap (each bitmap
       maintains its own transformation).  Every drawing operation after this call  will  be  transformed  using
       this  transformation.   Call  this  function  with  an  identity  transformation to return to the default
       behaviour.

       This function does nothing if there is no target bitmap.

       The parameter is passed by reference as an optimization to avoid the  overhead  of  stack  copying.   The
       reference will not be stored in the Allegro library so it is safe to pass references to local variables.

              void setup_my_transformation(void)
              {
                 ALLEGRO_TRANSFORM transform;
                 al_translate_transform(&transform, 5, 10);
                 al_use_transform(&transform);
              }

       Parameters:

       • trans - Transformation to use

       al_use_transform - Allegro 5 API

al_get_current_transform(3alleg5), al_transform_coordinates(3alleg5)

Allegro reference manual                                                               al_use_transform(3alleg5)

              #include <allegro5/allegro.h>

              void al_use_transform(const ALLEGRO_TRANSFORM *trans)