filters/seascape

 
var game = new Phaser.Game(800, 600, Phaser.AUTO, 'phaser-example', { create: create, update: update });

var filter;
var sprite;

function create() {

    //  From http://glslsandbox.com/e#20461.1

    var fragmentSrc = [
        "precision mediump float;",
        "uniform float     time;",
        "uniform vec2      resolution;",
        "uniform vec2      mouse;",

        "// Seascape by Alexander Alekseev aka TDM - 2014",
        "// License Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.",

        "// Mahmud Yuldashev modified",

        "float iGlobalTime=time;",
        "vec2 iResolution=resolution;",
        "vec3 iMouse=vec3(mouse,-3.0);",


        "const int NUM_STEPS = 38;",
        "const float PI     = 3.14159265;",
        "const float EPSILON    = 1e-4;",
        "float EPSILON_NRM  = 0.1 / iResolution.x;",

        "// sea",
        "const int ITER_FRAGMENT = 5;",
        "const float SEA_HEIGHT = 1.6;",
        "const float SEA_CHOPPY = 2.0;",
        "const float SEA_SPEED = 1.8;",
        "const float SEA_FREQ = 0.16;",
        "const vec3 SEA_BASE = vec3(0.1,0.19,0.22);",
        "const vec3 SEA_WATER_COLOR = vec3(0.8,0.9,0.6);",
        "const float SKY_INTENSITY = 1.0;",
        "float SEA_TIME = iGlobalTime * SEA_SPEED;",

        "// math",
        "mat4 fromEuler(vec3 ang) {",
            "vec2 a1 = vec2(sin(ang.x),cos(ang.x));",
            "vec2 a2 = vec2(sin(ang.y),cos(ang.y));",
            "vec2 a3 = vec2(sin(ang.z),cos(ang.z));",
            "mat4 m;",
            "m[0] = vec4(a1.y*a3.y+a1.x*a2.x*a3.x,a1.y*a2.x*a3.x+a3.y*a1.x,-a2.y*a3.x,0.0);",
            "m[1] = vec4(-a2.y*a1.x,a1.y*a2.y,a2.x,0.0);",
            "m[2] = vec4(a3.y*a1.x*a2.x+a1.y*a3.x,a1.x*a3.x-a1.y*a3.y*a2.x,a2.y*a3.y,0.0);",
            "m[3] = vec4(0.0,0.0,0.0,1.0);",
            "return m;",
        "}",
        "vec3 rotate(vec3 v, mat4 m) {",
            "return vec3(dot(v,m[0].xyz),dot(v,m[1].xyz),dot(v,m[2].xyz));",
        "}",
        "float hash( vec2 p ) {",
            "float h = dot(p,vec2(127.1,311.7));",
            "return fract(sin(h)*43758.5453123);",
        "}",
        "float noise( in vec2 p ) {",
            "vec2 i = floor( p );",
            "vec2 f = fract( p );",
            "vec2 u = f*f*(3.0-2.0*f);",
            "return -1.0+2.0*mix( mix( hash( i + vec2(0.0,0.0) ),",
            "hash( i + vec2(1.0,0.0) ), u.x),",
            "mix( hash( i + vec2(0.0,1.0) ),",
            "hash( i + vec2(1.0,1.0) ), u.x), u.y);",
        "}",


        "// lighting",
        "float diffuse(vec3 n,vec3 l,float p) { return pow(dot(n,l) * 0.4 + 0.6,p); }",
        "float specular(vec3 n,vec3 l,vec3 e,float s) {",
            "float nrm = (s + 8.0) / (3.1415 * 8.0);",
            "return pow(max(dot(reflect(e,n),l),0.0),s) * nrm;",
        "}",

        "// sky",
        "vec3 sky_color(vec3 e) {",
            "e.y = max(e.y,0.0);",
            "vec3 ret;",
            "ret.x = pow(1.0-e.y,2.0);",
            "ret.y = 1.0-e.y;",
            "ret.z = 0.6+(1.0-e.y)*0.4;",
            "return ret * SKY_INTENSITY;",
        "}",

        "// sea",
        "float sea_octave(vec2 uv, float choppy) {",
            "uv += noise(uv);",
            "vec2 wv = 1.0-abs(sin(uv));",
            "vec2 swv = abs(cos(uv));",
            "wv = mix(wv,swv,wv);",
            "return pow(1.0-pow(wv.x * wv.y,0.65),choppy);",
        "}",

        "float map_detailed(vec3 p) {",
            "float freq = SEA_FREQ;",
            "float amp = SEA_HEIGHT;",
            "float choppy = SEA_CHOPPY;",
            "vec2 uv = p.xz; uv.x *= 0.75;",
            "mat2 m = mat2(1.6,1.2,-1.2,1.6);",

            "float d, h = 0.0;",
            "for(int i = 0; i < ITER_FRAGMENT; i++) {",
                "d = sea_octave((uv+SEA_TIME)*freq,choppy);",
                "d += sea_octave((uv-SEA_TIME)*freq,choppy);",
                "h += d * amp;",
                "uv *= m; freq *= 1.9; amp *= 0.22;",
                "choppy = mix(choppy,1.0,0.2);",
            "}",
            "return p.y - h;",
        "}",

        "float map(vec3 p) {",
            "return map_detailed(p);",
        "}",
        "vec3 sea_color(in vec3 p, in vec3 n, in vec3 eye, in vec3 dist) {",
            "float fresnel_o = 1.0 - max(dot(n,-eye),0.0);",
            "float fresnel = pow(fresnel_o,3.0) * 0.65;",

            "// reflection",
            "vec3 refl = sky_color(reflect(eye,n));",

            "// color",
            "vec3 ret = SEA_BASE;",
            "ret = mix(ret,refl,fresnel);",

            "// wave peaks",
            "float atten = max(1.0 - dot(dist,dist) * 0.001, 0.0);",
            "ret += SEA_WATER_COLOR * (p.y - SEA_HEIGHT) * 0.18 * atten;",

            "return ret;",
        "}",

        "// tracing",
        "vec3 getNormal(vec3 p, float eps) {",
            "vec3 n;",
            "n.y = map_detailed(p);",
            "n.x = map_detailed(vec3(p.x+eps,p.y,p.z)) - n.y;",
            "n.z = map_detailed(vec3(p.x,p.y,p.z+eps)) - n.y;",
            "n.y = eps;",
            "return normalize(n);",
        "}",
        "float hftracing(vec3 ori, vec3 dir, out vec3 p) {",
            "float tm = 0.0;",
            "float tx = 1000.0;",
            "float hx = 1.0;",
            "float hm = 0.0;",
            "float tmid = 1.0;",
            "for(int i = 0; i < NUM_STEPS; i++) {",
                "//tmid = mix(tm,tx, hm/(hm-hx));",
                "p = ori + dir * tmid;",
                "tmid += map(p);",

            "}",
            "return tmid;",
        "}",

        "// main",
        "void main(void) {",
            "vec2 uv = gl_FragCoord.xy / iResolution.xy;",
            "uv = uv * 2.0 - 1.0;",
            "uv.x *= iResolution.x / iResolution.y;",
            "float time = iGlobalTime * 0.3;",

            "// ray",
            "vec3 ang = vec3(sin(time*3.0)*0.1,sin(time)*0.2+0.4,time);",
            "if(iMouse.z > 0.0) ang = vec3(0.0,clamp(2.0-iMouse.y*0.01,-0.3,PI),iMouse.x*0.01);",
            "mat4 rot = fromEuler(ang);",

            "vec3 ori = vec3(0.0,0.2,time*1.0);",
            "ori.y += abs(map_detailed(-ori));",
            "vec3 dir = normalize(vec3(uv.xy,-1.0));",
            "dir = rotate(normalize(dir),rot);",

            "// tracing",
            "vec3 p;",
            "float dens = hftracing(ori,dir,p);",
            "vec3 dist = p - ori;",
            "vec3 n = getNormal(p, dot(dist,dist)*EPSILON_NRM);",

            "// color",
            "vec3 color = sea_color(p,n,dir,dist);",
            "vec3 light = normalize(vec3(0.0,1.0,0.8));",
            "color += vec3(diffuse(n,light,80.0) * SEA_WATER_COLOR) * 0.12;",
            "color += vec3(specular(n,light,dir,60.0));",

            "// post",
            "color = mix(sky_color(dir),color, clamp(1.0-length(dist)/100.0,0.0,1.0));",
            "color = pow(color,vec3(0.75));",
            "gl_FragColor = vec4(color,1.0);",
        "}"
    ];

    filter = new Phaser.Filter(game, null, fragmentSrc);
    filter.setResolution(800, 600);

    sprite = game.add.sprite();
    sprite.width = 800;
    sprite.height = 600;

    sprite.filters = [ filter ];

}

function update() {

    filter.update();

}