#include "C:\Program Files\Autodesk\3ds Max 2021\OSL\vector2.h"
#define vec2 vector2
#define vec3 vector
#include "C:\Program Files\Autodesk\3ds Max 2021\OSL\vector4.h"
#define vec4 vector4

vec2 cmul
(
    vec2 a,
    vec2 b
)
{
    return vec2( a.x*b.x - a.y*b.y, a.x*b.y + a.y*b.x );
}

vec3 ACESFilm( vec3 x ) {
    float a = 2.51;
    float b = 0.03;
    float c = 2.43;
    float d = 0.59;
    float e = 0.14;
    return clamp((x*(a*x+b))/(x*(c*x+d)+e), 0.0, 1.0);
}



vec2 csqr
(
    vec2 a
)
{
    return vec2( a.x*a.x - a.y*a.y, 2.*a.x*a.y  );
}


matrix rot
(
    float a
)
{
    return matrix(cos(a),sin(a),0,0,-sin(a),cos(a),0,0,0,0,0,0,0,0,0,0);
}


vec2 iSphere
(
    vec3 ro,
    vec3 rd,
    vec4 sph
)
{
    vec3 oc = ro - vec3(sph.x,sph.y,sph.z);
    float b = dot( oc, rd );
    float c = dot( oc, oc ) - sph.w*sph.w;
    float h = b*b - c;
    if( h<0.0 ) return vec2(-1.0,-1.0);
    h = sqrt(h);

    return vec2(-b-h, -b+h );
}

float map( output vec3 p, float Time, int Animate, int Iterations) {

    float res = 0.;
    vec3 c = p;
    for (int i = 0; i < Iterations; ++i) {

        if(Animate)
        {
        p =.7*abs(p+cos(Time*0.15+1.6)*0.15)/dot(p,p) -.7+cos(Time*0.15)*0.15;

        }
        else
        {
       p =.7*abs(p)/dot(p,p) -.7;
     }
        vec2 pyz= csqr(vec2(p[1],p[2]));
        p= vec3(p[0],pyz.x,pyz.y);
        p = vec3(p[2],p[0],p[1]);
        res += exp(-19. * abs(dot(p,c)));
    }
    return res/2.;
}


vec3 raymarch
(
    vec3 ro,
    vec3 rd,
    vec2 tminmax,
    float Time,
    int Animate,
    int Iterations

)
{
    float t = tminmax.x;
    float dt = .02;
    //float dt = .2 - .195*cos(iTime*.05);//animated
    vec3 col= vec3(0.);
    float c = 0.;
    for( int i=0; i<64; i++ )
    {
        t+=dt*exp(-2.*c);
        if(t>tminmax.y)break;
        vec3 pos = ro+t*rd;

        c = map(ro+t*rd,Time,Animate,Iterations);

        col = .99*col+ .08*vec3(c*c, c, c*c*c);//green
        //col = .99*col+ .08*vec3(c*c*c, c*c, c);//blue
    }
    return col;
}

shader FractalMarble
(
    point Po = P,
    float Time = 0,
    float zoom = 1,
    float Offsetx = 0,
    float Offsety = 0,
    int Iterations = 10,

                  int    Animate   = 1
    [[ string widget="checkBox" ]],



          int    ACESFilmMode   = 1
    [[ string widget="checkBox" ]],

    output color Out = 0,
)
{
    vec2 q = vec2(Po[0],Po[1]);
    vec2 p = -1.0 + 2.0 * q;
    vec2 m = vec2(Offsetx,Offsety);
    m-=.5;

    // camera
    vec3 ro = zoom*vec3(4.);
    vec3 royz = vec3(ro[1],ro[2],0);
    royz =transform( rot(m.y), royz );
    ro = vec3(ro[0],royz[0],royz[1]);
    vec3 roxz = vec3(ro[0],ro[2],0);
    roxz =transform( rot(m.x+ 0.1*Time), roxz );
    ro = vec3(ro[0],roxz[0],roxz[1]);
    vec3 ta = vec3( 0.0 , 0.0, 0.0 );
    vec3 ww = normalize( ta - ro );
    vec3 uu = normalize( cross(ww,vec3(0.0,1.0,0.0) ) );
    vec3 vv = normalize( cross(uu,ww));
    vec3 rd = normalize( p.x*uu + p.y*vv + 4.0*ww );
    vec2 tmm = iSphere( ro, rd, vec4(0.,0.,0.,2.) );

    // raymarch
    vec3 col = raymarch(ro,rd,tmm,Time,Animate,Iterations);
  //  if (tmm.x<0.)col = texture(iChannel0, rd).rgb;

    vec3 nor=(ro+tmm.x*rd)/2.;
    nor = reflect(rd, nor);
    float fre = pow(.5+ clamp(dot(nor,rd),0.0,1.0), 3. )*1.3;

    // shade

    col =  .5 *(log(1.+col));
    col = clamp(col,0.,1.);
    if(ACESFilmMode)
    {col = ACESFilm(col);
   }

    Out = vec3( col);
    Out = pow(Out,2.2);

}