examples/shader.lisp

   1 (require '#:asdf)
   2 (asdf:oos 'asdf:load-op '#:cl-glfw)
   3 (asdf:oos 'asdf:load-op '#:cl-glfw-opengl-version_2_0)
   4 (asdf:oos 'asdf:load-op '#:cl-glfw-glu)
   5
   6 (defparameter *shader-program* nil)
   7 (defparameter *uniform-time* nil)
   8
   9 (glfw:do-window (:title "An OpenGL 2.0 Shader Example")
  10     ((gl:with-setup-projection
  11        (glu:perspective 45 4/3 0.1 50))
  12      (setf *shader-program*
  13            (gl:make-program
  14             (gl:make-shader gl:+vertex-shader+ "
  15 varying vec3 colour;
  16 void main()
  17 {
  18   colour = gl_Color.rgb;
  19   gl_Position = ftransform();
  20 }
  21 ")
  22             (gl:make-shader gl:+fragment-shader+ "
  23 uniform float time;
  24 varying vec3 colour;
  25 const float pi2=2.0*3.14159265;
  26 void main()
  27 {
  28   gl_FragColor = vec4(pow(sin(colour.r*pi2*4.0+mod(time*8.0,pi2)),2.0),
  29                       pow(sin(colour.g*pi2*4.0+mod(time*8.0,pi2)),2.0),
  30                       pow(sin(colour.b*pi2*4.0+mod(time*8.0,pi2)),2.0),
  31                       1.0);
  32 }
  33 ")))
  34      (gl:use-program *shader-program*)
  35      (setf *uniform-time* (gl:get-uniform-location *shader-program* "time")))
  36   (gl:clear gl:+color-buffer-bit+)
  37   (gl:load-identity)
  38   (gl:translate-f 0 0 -5)
  39   (gl:rotate-d (* 10 (glfw:get-time)) 1 1 0)
  40   (gl:rotate-d (* 90 (glfw:get-time)) 0 0 1)
  41   (gl:uniform-1f *uniform-time* (coerce (glfw:get-time) 'single-float))
  42   (gl:with-begin gl:+triangles+
  43     (gl:color-3f 1 0 0) (gl:vertex-3f  1  0 0)
  44     (gl:color-3f 0 1 0) (gl:vertex-3f -1  1 0)
  45     (gl:color-3f 0 0 1) (gl:vertex-3f -1 -1 0)))