ALLEGRO_VERTEX_DECL - Allegro 5 API

       A  vertex  declaration.   This  opaque structure is responsible for describing the format and layout of a
       user defined custom vertex.  It is created and destroyed by specialized functions.

       ALLEGRO_VERTEX_DECL - Allegro 5 API

al_create_vertex_decl(3alleg5), al_destroy_vertex_decl(3alleg5), ALLEGRO_VERTEX_ELEMENT(3alleg5)

Allegro reference manual                                                            ALLEGRO_VERTEX_DECL(3alleg5)

              #include <allegro5/allegro_primitives.h>

              typedef struct ALLEGRO_VERTEX_DECL ALLEGRO_VERTEX_DECL;