;;;; basic-shader.lisp (Lisp shader code)

#|
(define-shader basic-shader
  (:version 330)
  (:vertex-shader
   :in ((vert-pos :type :vec3 :location 0)
        (vert-uv :type :vec2 :location 1))
   :out ((uv :type :vec2))
   :uniform ((model :type :mat4)
             (view :type :mat4)
             (proj :type :mat4))
   :main ((setf *position* (* proj view model (vec4 vert-pos 1.0)))
          (setf uv vert-uv)))
  (:fragment-shader
   :in ((uv :type :vec2))
   :out ((*frag-colour* :type :vec4))
   :uniform ((main-tex :type :sampler-2d)
             (colour :type :vec4))
   :main ((setf *frag-colour* (* (sample-texture main-tex uv) colour)))))
|#

(define-shader basic-shader
    (:in ((vert-pos :type :vec3 :location 0)
          (vert-uv :type :vec2 :location 1))
     :out ((*frag-colour* :type :vec4))
     :uniform ((model :type :mat4)
               (view :type :mat4)
               (proj :type :mat4)
               (main-tex :type :sampler-2d)
               (colour :type :vec4)))
  :version 330
  :vert ((setf *position* (* proj view model (vec4 vert-pos 1.0))))
  :frag ((setf *frag-colour* (* (sample-texture main-tex vert-uv) colour))))