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

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