SatorImaging_FastProceduralOcean.cginc

// https://www.shadertoy.com/view/MdXyzX
//afl_ext 2017-2019
/*
#define DRAG_MULT 0.048
#define ITERATIONS_RAYMARCH 13
#define ITERATIONS_NORMAL 48

#define Mouse (iMouse.xy / iResolution.xy)
#define Resolution (iResolution.xy)
#define Time (iTime)
*/

#define POSITION_LIMIT 1000


float2 wavedx(float2 position, float2 direction, float speed, float frequency, float timeshift)
{
    float x = dot(direction, position) * frequency + timeshift * speed;
    float wave = exp(sin(x) - 1.0);
    float dx = wave * cos(x);
    return float2(wave, -dx);
}

float getwaves(float2 position, int iterations, float waveTime, float waveScale, float waveSharpness)
{
    float iter = 0.0; //0.0;
    float phase = waveScale; //6.0;
    float speed = 2.0; //2.0;
    float weight = 1.0; // 1.0;
    float w = 0.0;//    0.0;
    float ws = 0.0;//   0.0;
    for (int i = 0; i < iterations; i++)
    {
        float2 p = float2(sin(iter), cos(iter));
        float2 res = wavedx(position, p, speed, phase, waveTime);
        position += normalize(p) * res.y * weight * waveSharpness; // * DRAG_MULT;
        w += res.x * weight;
        iter += 12.0;
        ws += weight;
        weight = lerp(weight, 0.0, 0.2);
        phase *= 1.18;
        speed *= 1.07;
    }
    return w / ws;
}

/*
float raymarchwater(float3 camera, float3 start, float3 end, float depth)
{
    float3 pos = start;
    float h = 0.0;
    float hupper = depth;
    float hlower = 0.0;
    float2 zer = float2(0.0);
    float3 dir = normalize(end - start);
    for (int i = 0; i < 318; i++)
    {
        h = getwaves(pos.xz * 0.1, ITERATIONS_RAYMARCH) * depth - depth;
        if (h + 0.01 > pos.y)
        {
            return distance(pos, camera);
        }
        pos += dir * (pos.y - h);
    }
    return -1.0;
}
*/

float H = 0.0;
float3 normal(float2 pos, float e, float depth, float waveTime, int iterations, float waveScale, float waveSharpness)
{
    pos = fmod(pos, POSITION_LIMIT);

    float2 ex = float2(e, 0);
    H = getwaves(pos.xy * 0.1, iterations, waveTime, waveScale, waveSharpness) * depth;
    float3 a = float3(pos.x, H, pos.y);
    return normalize(cross(normalize(a - float3(pos.x - e, getwaves(pos.xy * 0.1 - ex.xy * 0.1, iterations, waveTime, waveScale, waveSharpness) * depth, pos.y)),
                           normalize(a - float3(pos.x, getwaves(pos.xy * 0.1 + ex.yx * 0.1, iterations, waveTime, waveScale, waveSharpness) * depth, pos.y + e))));
}

/*
mat3 rotmat(float3 axis, float angle)
{
    axis = normalize(axis);
    float s = sin(angle);
    float c = cos(angle);
    float oc = 1.0 - c;
    return mat3(oc * axis.x * axis.x + c, oc * axis.x * axis.y - axis.z * s, oc * axis.z * axis.x + axis.y * s,
	oc * axis.x * axis.y + axis.z * s, oc * axis.y * axis.y + c, oc * axis.y * axis.z - axis.x * s,
	oc * axis.z * axis.x - axis.y * s, oc * axis.y * axis.z + axis.x * s, oc * axis.z * axis.z + c);
}
*/

/*
float3 getRay(float2 uv)
{
    uv = (uv * 2.0 - 1.0) * float2(Resolution.x / Resolution.y, 1.0);
    float3 proj = normalize(float3(uv.x, uv.y, 1.0) + float3(uv.x, uv.y, -1.0) * pow(length(uv), 2.0) * 0.05);
    if (Resolution.x < 400.0)
        return proj;
    float3 ray = rotmat(float3(0.0, -1.0, 0.0), 3.0 * (Mouse.x * 2.0 - 1.0)) * rotmat(float3(1.0, 0.0, 0.0), 1.5 * (Mouse.y * 2.0 - 1.0)) * proj;
    return ray;
}
*/

/*
float intersectPlane(float3 origin, float3 direction, float3point, float3 normal)
{
    return clamp(dot(point
    -origin, normal) / dot(direction, normal), -1.0, 9991999.0);
}
*/

/*
float3 extra_cheap_atmosphere(float3 raydir, float3 sundir)
{
    sundir.y = max(sundir.y, -0.07);
    float special_trick = 1.0 / (raydir.y * 1.0 + 0.1);
    float special_trick2 = 1.0 / (sundir.y * 11.0 + 1.0);
    float raysundt = pow(abs(dot(sundir, raydir)), 2.0);
    float sundt = pow(max(0.0, dot(sundir, raydir)), 8.0);
    float mymie = sundt * special_trick * 0.2;

//    float3 suncolor = lerp(float3(1.0), max(float3(0.0), float3(1.0) - float3(5.5, 13.0, 22.4) / 22.4), float3(special_trick2));
    float3 suncolor = float3(1.0, 1.0, 1.0) - float3(5.5, 13.0, 22.4) / float3(22.4, 22.4, 22.4);
    suncolor = float3(
                    lerp(1, max(0, suncolor.x), special_trick2),
                    lerp(1, max(0, suncolor.y), special_trick2),
                    lerp(1, max(0, suncolor.z), special_trick2)
    );

    float3 bluesky = float3(5.5, 13.0, 22.4) / 22.4 * suncolor;

//    float3 bluesky2 = max(float3(0.0), bluesky - float3(5.5, 13.0, 22.4) * 0.002 * (special_trick + -6.0 * sundir.y * sundir.y));
    float3 bluesky2 = max(float3(0, 0, 0), bluesky - float3(5.5, 13.0, 22.4) * 0.002 * (special_trick + -6.0 * sundir.y * sundir.y));

    bluesky2 *= special_trick * (0.24 + raysundt * 0.24);
    return bluesky2 * (1.0 + 1.0 * pow(1.0 - raydir.y, 3.0)) + mymie * suncolor;
}
*/

/*
float3 getatm(float3 ray)
{
    return extra_cheap_atmosphere(ray, normalize(float3(1.0))) * 0.5;
    
}
*/

/*
float sun(float3 ray)
{
    float3 sd = normalize(float3(1,1,1));
    return pow(max(0.0, dot(ray, sd)), 528.0) * 110.0;
}
*/

/*
float3 aces_tonemap(float3 color)
{
    mat3 m1 = mat3(
        0.59719, 0.07600, 0.02840,
        0.35458, 0.90834, 0.13383,
        0.04823, 0.01566, 0.83777
	);
    mat3 m2 = mat3(
        1.60475, -0.10208, -0.00327,
        -0.53108, 1.10813, -0.07276,
        -0.07367, -0.00605, 1.07602
	);
    float3 v = m1 * color;
    float3 a = v * (v + 0.0245786) - 0.000090537;
    float3 b = v * (0.983729 * v + 0.4329510) + 0.238081;
    return pow(clamp(m2 * (a / b), 0.0, 1.0), float3(1.0 / 2.2));
}
*/

/*
void mainImage(out float4 fragColor, in float2 fragCoord)
{
    float2 uv = fragCoord.xy / iResolution.xy;
 	
    float waterdepth = 2.1;
    float3 wfloor = float3(0.0, -waterdepth, 0.0);
    float3 wceil = float3(0.0, 0.0, 0.0);
    float3 orig = float3(0.0, 2.0, 0.0);
    float3 ray = getRay(uv);
    float hihit = intersectPlane(orig, ray, wceil, float3(0.0, 1.0, 0.0));
    if (ray.y >= -0.01)
    {
        float3 C = getatm(ray) * 2.0 + sun(ray);
        //tonemapping
        C = aces_tonemap(C);
        fragColor = float4(C, 1.0);
        return;
    }
    float lohit = intersectPlane(orig, ray, wfloor, float3(0.0, 1.0, 0.0));
    float3 hipos = orig + ray * hihit;
    float3 lopos = orig + ray * lohit;
    float dist = raymarchwater(orig, hipos, lopos, waterdepth);
    float3 pos = orig + ray * dist;

    float3 N = normal(pos.xz, 0.001, waterdepth);
    float2 velocity = N.xz * (1.0 - N.y);
    N = mix(float3(0.0, 1.0, 0.0), N, 1.0 / (dist * dist * 0.01 + 1.0));
    float3 R = reflect(ray, N);
    float fresnel = (0.04 + (1.0 - 0.04) * (pow(1.0 - max(0.0, dot(-N, ray)), 5.0)));
	
    float3 C = fresnel * getatm(R) * 2.0 + fresnel * sun(R);
    //tonemapping
    C = aces_tonemap(C);
    
    fragColor = float4(C, 1.0);
}
*/