ALLEGRO_SHADER_PLATFORM - Allegro 5 API

       The underlying platform which the ALLEGRO_SHADER(3alleg5) is built on top of, which dictates the language
       used to program the shader.

       • ALLEGRO_SHADER_AUTO - Pick a platform automatically given the current display flags.

       • ALLEGRO_SHADER_GLSL - OpenGL Shading Language

       • ALLEGRO_SHADER_HLSL - High Level Shader Language (for Direct3D)

       • ALLEGRO_SHADER_AUTO_MINIMAL - Like ALLEGRO_SHADER_AUTO, but pick a more minimal implementation that may
         not support alpha testing.

       • ALLEGRO_SHADER_GLSL_MINIMAL - Minimal GLSL shader.

       • ALLEGRO_SHADER_HLSL_MINIMAL - Minimal HLSL shader.

       • ALLEGRO_SHADER_HLSL_SM_3_0 - HLSL shader using shader model 3_0.

       ALLEGRO_SHADER_PLATFORM - Allegro 5 API

       5.1.0

Allegro reference manual                                                        ALLEGRO_SHADER_PLATFORM(3alleg5)

              #include <allegro5/allegro.h>

              typedef enum ALLEGRO_SHADER_PLATFORM ALLEGRO_SHADER_PLATFORM;