al_compose_transform - Allegro 5 API

       Compose (combine) two transformations by a matrix multiplication.

              trans := trans other

       Note  that  the  order  of  matrix  multiplications  is  important.   The effect of applying the combined
       transform will be as if first applying trans and then applying other and not the other way around.

       Parameters:

       • trans - Transformation to alter

       • other - Transformation used to transform trans

       al_compose_transform - Allegro 5 API

al_translate_transform(3alleg5), al_rotate_transform(3alleg5), al_scale_transform(3alleg5)

Allegro reference manual                                                           al_compose_transform(3alleg5)

              #include <allegro5/allegro.h>

              void al_compose_transform(ALLEGRO_TRANSFORM *trans, const ALLEGRO_TRANSFORM *other)