NAME

       set_projection_viewport  -  Sets the viewport used to scale the output of persp_project().
       Allegro game programming library.

SYNOPSIS

       #include <allegro.h>

       void set_projection_viewport(int x, int y, int w, int h);

DESCRIPTION

       Sets the viewport used to scale the output  of  the  persp_project()  function.  Pass  the
       dimensions  of  the  screen  area  you  want  to  draw onto, which will typically be 0, 0,
       SCREEN_W, and SCREEN_H.  Also  don't  forget  to  pass  an  appropriate  aspect  ratio  to
       get_camera_matrix later. The width and height you specify here will determine how big your
       viewport is in 3d space. So if an object in your 3D space is w units wide,  it  will  fill
       the  complete  screen  when  you  run into it (i.e., if it has a distance of 1.0 after the
       camera matrix was applied. The fov and aspect-ratio parameters to  get_camera_matrix  also
       apply some scaling though, so this isn't always completely true). If you pass -1/-1/2/2 as
       parameters, no extra scaling will be performed by the projection.

SEE ALSO

       persp_project(3alleg4),  get_camera_matrix(3alleg4),   ex3d(3alleg4),   excamera(3alleg4),
       exquat(3alleg4), exscn3d(3alleg4), exstars(3alleg4), exzbuf(3alleg4)