END OF AN ERA, FRACTALFORUMS.COM IS CONTINUED ON FRACTALFORUMS.ORG

float DE(vec3 z)
{
float r;
float r2=0.;
int n = 0;
vec3 rmin=vec3(0.);
vec3 zoff=vec3(0.);
vec3 zstore=vec3(0.);
while (n < Iterations) {
z*=rot;
z=abs(z);
zstore=z;
rmin=vec3(100.,100.,100.);
//  x part  
r=(z.x-OffSet.x);
r=r*r;
if (r<rmin.x) { rmin.x=r;zoff.x= OffSet.x;}

r=(z.x)*z.x;
if (r<rmin.x) { rmin.x=r;zoff.x= 0.;}
// y part
r=(z.y-OffSet.y);
r=r*r;
if (r<rmin.y) { rmin.y=r;zoff.y= OffSet.y;}

r=(z.y)*z.y;
if (r<rmin.y) { rmin.y=r;zoff.y= 0.;}
//z part
r=(z.z-OffSet.z); r=r*r;
if (r<rmin.z) { rmin.z=r;zoff.z= OffSet.z;}

r=(z.z)*z.z;
if (r<rmin.z) { rmin.z=r;zoff.z= 0.;}

z=Scale*z-zoff*(Scale-1.0);

if (!Stellated) { // you can take out the not Stellated part here
if (abs(zstore.x)<abs(zstore.y)) {
if (abs(zstore.x)<abs(zstore.z)) {
z.x+=zoff.x;
} else {
z.z+=zoff.z;
}
} else {
if (abs(zstore.y)<abs(zstore.z)) {
z.y+=zoff.y;
} else {
z.z+=zoff.z;
}
}
} else { //  and just use the following section
if (rmin.x<rmin.y) { // if you do, remove the zstore variable, as it is
if (rmin.x<rmin.z) { // superfluous.  hahah... superfluous....  :D
z.x+=zoff.x;
} else {
z.z+=zoff.z;
}
} else {
if (rmin.y<rmin.z) {
z.y+=zoff.y;
} else {
z.z+=zoff.z;
}
}
}
if (n<ColorIterations) orbitTrap = min(orbitTrap, (vec4(abs(z),dot(z,z))));

n++;
}

r2=(max(abs(z.x),max(abs(z.y),abs(z.z)))-1.);

return r2*pow(Scale,float(-n));
}

vec3 example (vec3 hrmm) {
  if (check==1) { code  }

  some code.....

  if (check==2)  { code }

 some code

  if (check==3) { code }

  some code ...   etc.

void main() {//first pass - render from light's perspective to get a depth texture
vec2 pt=(gl_FragCoord.xy/vec2(resolution))*PI;//map screen coords to sphere
vec3 rayDir = vec3(sin(pt.y)*cos(pt.x),cos(pt.y),sin(pt.y)*sin(pt.x));
vec3 ray = lightPosition;//place the camera at the light
float rayLen=0.0,dist=lightFallOff;
for(int iSteps=0;iSteps<MaxSteps && dist>=HitDistance && rayLen<=lightFallOff;iSteps++){
rayLen+=dist=DE(ray+rayLen*rayDir);
}//march until you hit something or the light gets too weak
rayLen=clamp(rayLen/lightFallOff,0.0,0.99);
gl_FragColor = Encode(rayLen);//for non-float textures just shove the float into bytes
gl_FragDepth = rayLen;
}
void main() {//second pass - draw the scene as usual then fill in fog
... usual rendering code here ...
... rayLen has depth of scene, ray is position of hit, color has color:)

for(float rl=0.0;rl<rayLen;rl+=fogStep){//take small steps along the ray checking depth
vec3 lightCamDir=ray+rayDir*rl-lightPosition;//get the direction FROM light
float d=length(lightCamDir);
lightCamDir=normalize(lightCamDir);
float phi=acos(lightCamDir.y);//map back to screen coords
vec2 pt=vec2(acos(lightCamDir.x/sin(phi)),phi)/3.1416;
//add fog light only if the distance to the light is less than that in texture
if(d<Decode(texture2D(tex,pt))*lightFallOff)color.rgb+=fogColor/(d*d);
}
}