extra/bunny/cel-shaded/cel-shaded.factor

   1 USING: arrays bunny.model continuations destructors kernel
   2 multiline opengl opengl.shaders opengl.capabilities opengl.gl
   3 sequences accessors combinators ;
   4 IN: bunny.cel-shaded
   5
   6 STRING: vertex-shader-source
   7 varying vec3 position, normal, viewer;
   8
   9 void
  10 main()
  11 {
  12     gl_Position = ftransform();
  13
  14     position = gl_Vertex.xyz;
  15     normal = gl_Normal;
  16     viewer = vec3(0, 0, 1) * gl_NormalMatrix;
  17 }
  18
  19 ;
  20
  21 STRING: cel-shaded-fragment-shader-lib-source
  22 varying vec3 position, normal, viewer;
  23 uniform vec3 light_direction;
  24 uniform vec4 color;
  25 uniform vec4 ambient, diffuse;
  26 uniform float shininess;
  27
  28 float
  29 modulate(vec3 direction, vec3 normal)
  30 {
  31     return dot(direction, normal) * 0.5 + 0.5;
  32 }
  33
  34 float
  35 cel(float m)
  36 {
  37     return smoothstep(0.25, 0.255, m) * 0.4 + smoothstep(0.695, 0.70, m) * 0.5;
  38 }
  39
  40 vec4
  41 cel_light()
  42 {
  43     vec3 direction = normalize(light_direction - position);
  44     vec3 reflection = reflect(direction, normal);
  45     vec4 ad = (ambient + diffuse * vec4(vec3(cel(modulate(direction, normal))), 1));
  46     float s = cel(pow(max(dot(-reflection, viewer), 0.0), shininess));
  47     return ad * color + vec4(vec3(s), 0);
  48 }
  49
  50 ;
  51
  52 STRING: cel-shaded-fragment-shader-main-source
  53 vec4 cel_light();
  54
  55 void
  56 main()
  57 {
  58     gl_FragColor = cel_light();
  59 }
  60
  61 ;
  62
  63 TUPLE: bunny-cel-shaded program ;
  64
  65 : cel-shading-supported? ( -- ? )
  66     "2.0" { "GL_ARB_shader_objects" }
  67     has-gl-version-or-extensions? ;
  68
  69 : <bunny-cel-shaded> ( gadget -- draw )
  70     drop
  71     cel-shading-supported? [
  72         bunny-cel-shaded new
  73         vertex-shader-source <vertex-shader> check-gl-shader
  74         cel-shaded-fragment-shader-lib-source <fragment-shader> check-gl-shader
  75         cel-shaded-fragment-shader-main-source <fragment-shader> check-gl-shader
  76         3array <gl-program> check-gl-program
  77         >>program
  78     ] [ f ] if ;
  79
  80 : (draw-cel-shaded-bunny) ( geom program -- )
  81     [
  82         {
  83             [ "light_direction" glGetUniformLocation 1.0 -1.0 1.0 glUniform3f ]
  84             [ "color"           glGetUniformLocation 0.6 0.5 0.5 1.0 glUniform4f ]
  85             [ "ambient"         glGetUniformLocation 0.2 0.2 0.2 0.2 glUniform4f ]
  86             [ "diffuse"         glGetUniformLocation 0.8 0.8 0.8 0.8 glUniform4f ]
  87             [ "shininess"       glGetUniformLocation 100.0 glUniform1f ]
  88         } cleave bunny-geom
  89     ] with-gl-program ;
  90
  91 M: bunny-cel-shaded draw-bunny
  92     program>> (draw-cel-shaded-bunny) ;
  93
  94 M: bunny-cel-shaded dispose
  95     program>> delete-gl-program ;