shaders/scene_water.fs

   1 uniform sampler2D uTexMain;
   2 uniform sampler2D uTexDudv;
   3 uniform sampler2D uTexBack;
   4
   5 uniform vec2 uInvRes;
   6 uniform float uTime;
   7 uniform vec3 uCamera;
   8 uniform float uSurfaceY;
   9 uniform vec3 uBoard0;
  10 uniform vec3 uBoard1;
  11
  12 uniform vec3 uShoreColour;
  13 uniform vec3 uOceanColour;
  14
  15 #include "light_clearskies_stddef.glsl"
  16 #include "common_scene.glsl"
  17 #include "motion_vectors_fs.glsl"
  18
  19 vec4 water_surf( vec3 halfview, vec3 vnorm, float depthvalue,
  20                  vec4 beneath, vec4 above, vec4 dudva )
  21 {
  22    vec3 surface_tint = mix(uShoreColour, uOceanColour, depthvalue);
  23
  24    float ffresnel = pow(1.0-dot( vnorm, halfview ),5.0);
  25
  26    vec3 lightdir = vec3(0.95,0.0,-0.3);
  27    vec3 specdir = reflect( -lightdir, vnorm );
  28    float spec = pow(max(dot(halfview,specdir),0.0),20.0)*0.3;
  29
  30    // Depth
  31    float depthblend = pow( beneath.r, 0.8 );
  32
  33    // Foam
  34    float fband = fract( aCo.z*0.02+uTime*0.1+depthvalue*10.0 );
  35    fband = step( fband+dudva.a*0.8, 0.3 ) * max((1.0-depthvalue*4.0),0.0);
  36
  37    vec4 surf = mix( vec4(surface_tint,depthblend),
  38                     vec4(1.0,1.0,1.0,0.5), fband );
  39    surf.rgb = scene_compute_lighting( surf.rgb, aNorm.xyz, aWorldCo );
  40    surf.rgb = mix(surf.rgb, above.rgb, ffresnel );
  41    return surf;
  42 }
  43
  44 void main()
  45 {
  46    compute_motion_vectors();
  47
  48    // Create texture coords
  49    vec2 ssuv = gl_FragCoord.xy*uInvRes;
  50
  51    // Surface colour composite
  52    float depthvalue = clamp( -world_water_depth(aCo)*(1.0/25.0), 0.0,1.0 );
  53
  54    vec2 world_coord = aCo.xz * 0.008;
  55    vec4 time_offsets = vec4( uTime ) * vec4( 0.008, 0.006, 0.003, 0.03 );
  56    vec4 dudva = texture( uTexDudv, world_coord + time_offsets.xy )-0.5;
  57    vec4 dudvb = texture( uTexDudv, world_coord *7.0 - time_offsets.zw )-0.5;
  58
  59    vec3 surfnorm = dudva.rgb + dudvb.rgb;
  60    surfnorm = normalize(vec3(0.0,1.0,0.0) + dudva.xyz*0.4 + dudvb.xyz*0.1);
  61
  62    // Lighting
  63    vec3 halfview = -normalize( aCo-uCamera );
  64
  65    // Sample textures
  66    vec4 above = texture( uTexMain, ssuv+ surfnorm.xz*0.2 );
  67    vec4 beneath = texture( uTexBack, ssuv );
  68
  69    // Fog
  70    float fdist = pow(length( aCo.xz-uCamera.xz ) * 0.00047, 2.6);
  71
  72    // Composite
  73    vec4 vsurface = water_surf( halfview, surfnorm, depthvalue, beneath, above, dudva );
  74    vsurface.a -= fdist;
  75
  76    oColour = vsurface;
  77 }