shaders/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
  10 uniform vec3 uShoreColour;
  11 uniform vec3 uOceanColour;
  12
  13 in vec4 aColour;
  14 in vec2 aUv;
  15 in vec3 aNorm;
  16 in vec3 aCo;
  17 in vec3 aWorldCo;
  18
  19 #include "common_world.glsl"
  20 #include "motion_vectors_fs.glsl"
  21
  22 vec4 water_surf( vec3 halfview, vec3 vnorm, float depthvalue,
  23       vec4 beneath, vec4 above )
  24 {
  25    vec3 surface_tint = mix(uShoreColour, uOceanColour, depthvalue);
  26
  27    float ffresnel = pow(1.0-dot( vnorm, halfview ),5.0);
  28
  29    vec3 lightdir = vec3(0.95,0.0,-0.3);
  30    vec3 specdir = reflect( -lightdir, vnorm );
  31    float spec = pow(max(dot(halfview,specdir),0.0),20.0)*0.3;
  32
  33    // Depth
  34    float depthblend = pow( beneath.a,0.8 );
  35
  36    // Composite
  37    vec3 vsurface = mix(surface_tint, above.rgb, ffresnel );
  38    //vsurface += spec;
  39
  40    return vec4( vsurface,depthblend );
  41 }
  42
  43 void main()
  44 {
  45    compute_motion_vectors();
  46
  47    // Create texture coords
  48    vec2 ssuv = gl_FragCoord.xy*uInvRes;
  49
  50    // Surface colour composite
  51    float depthvalue = clamp( -world_depth_sample( aCo )*(1.0/25.0), 0.0, 1.0 );
  52
  53    vec2 world_coord = aCo.xz * 0.008;
  54    vec4 time_offsets = vec4( uTime ) * vec4( 0.008, 0.006, 0.003, 0.03 );
  55    vec4 dudva = texture( uTexDudv, world_coord + time_offsets.xy )-0.5;
  56    vec4 dudvb = texture( uTexDudv, world_coord *7.0 - time_offsets.zw )-0.5;
  57
  58    vec3 surfnorm = dudva.rgb + dudvb.rgb;
  59    surfnorm = normalize(vec3(0.0,1.0,0.0) + dudva.xyz*0.4 + dudvb.xyz*0.1);
  60
  61    // Foam
  62    float fband = fract( aCo.z*0.02+uTime*0.1+depthvalue*10.0 );
  63    fband = step( fband+dudva.a*0.8, 0.3 ) * max((1.0-depthvalue*4.0),0.0);
  64
  65    // Lighting
  66    vec3 halfview = -normalize( aCo-uCamera );
  67
  68    // Sample textures
  69    vec4 above = texture( uTexMain, ssuv+ surfnorm.xz*0.2 );
  70    vec4 beneath = texture( uTexBack, ssuv );
  71
  72    // Fog
  73    float fdist = pow(length( aCo.xz-uCamera.xz ) * 0.00047, 2.6);
  74
  75    // Composite
  76    vec4 vsurface = water_surf( halfview, surfnorm, depthvalue, beneath, above );
  77    vsurface.a -= fdist;
  78    oColour = mix( vsurface, vec4(1.0,1.0,1.0,0.5), fband );
  79 }