NAME

       ALLEGRO_SHADER_TYPE - Allegro 5 API

SYNOPSIS

              #include <allegro5/allegro.h>

              typedef enum ALLEGRO_SHADER_TYPE ALLEGRO_SHADER_TYPE;

DESCRIPTION

       Used  with  al_attach_shader_source(3alleg5)  and al_attach_shader_source_file(3alleg5) to
       specify how to interpret the attached source.

       ALLEGRO_VERTEX_SHADER
              A vertex shader is executed for each vertex it is  used  with.   The  program  will
              output exactly one vertex at a time.

              When  Allegro's  graphics  are  being  used  then  in  addition  to all vertices of
              primitives from the primitives addon, each  drawn  bitmap  also  consists  of  four
              vertices.

       ALLEGRO_PIXEL_SHADER
              A pixel shader is executed for each pixel it is used with.  The program will output
              exactly one pixel at a time - either in the backbuffer or  in  the  current  target
              bitmap.

              With  Allegro's  builtin  graphics  this means the shader is for example called for
              each destination pixel of the output of an al_draw_bitmap(3alleg5) call.

              A more accurate term for pixel shader would be  fragment  shader  since  one  final
              pixel  in the target bitmap is not necessarily composed of only a single output but
              of multiple fragments (for example when multi-sampling is being used).

SINCE

       5.1.0