HOUDINI - VEX - OSL CONVERSION

[machinainfinitum]

I’m looking for someone who can convert some OSL code to VEX code.
I have a fractal formula written in OSL that needs to be volume density output VEX.
For now the simple mandelbulb fractal conversion is enough but I'm looking for someone that could convert many other complex formulas.(200-300 lines of code).

New to Houdini, and can't find a way to get this working...after days of looking around, this forum is my last option.

OSL CODE TO CONVERT:

shader OslGeometry(
    int Iterations = 10,
    float Power = 2.0,
    float Bailout = 20,
    output _sdf c = _SDFDEF)
{
    vector pos = P;

	vector z = P;
	float dr = 1.0;
	float r = 0.0;
	for (int i = 0; i < Iterations ; i++) {
		r = length(z);
		if (r>Bailout) break;

		// convert to polar coordinates
		float theta = acos(z[2]/r);
		float phi = atan2(z[1],z[0]);
		dr =  pow( r, Power-1.0)*Power*dr + 1.0;

		// scale and rotate the point
		float zr = pow( r,Power);
		theta = theta*Power;
		phi = phi*Power;

		// convert back to cartesian coordinates
		z = zr*vector(sin(theta)*cos(phi), sin(phi)*sin(theta), cos(theta));
		z+=pos;
	}
	c.dist = 0.5*log(r)*r/dr;
}

 

OSL CODE THAT WORKS BUT NEED IT TO BE LIKE THE OSL:

 

function int Mandel(float x0, y0, z0; int Iterations){
    float x, y, z, xnew, ynew, znew, n=ch('n'), r, theta, phi;
    int i;
    
    x = x0;
    y = y0;
    z = z0;
    
    for(i=0; i < Iterations; i++){
		
        r = sqrt(x*x + y*y + z*z);
        theta = atan2(sqrt(x*x + y*y) , z);
        phi = atan2(y,x);
        
        xnew = pow(r, n) * sin(theta*n) * cos(phi*n) + x0;
        ynew = pow(r, n) * sin(theta*n) * sin(phi*n) + y0;
        znew = pow(r, n) * cos(theta*n) + z0;
        
        if(xnew*xnew + ynew*ynew + znew*znew > 8){
            return(i);
        }
        
        x = xnew;
        y = ynew;
        z = znew;
    }
    return(Iterations);
}
//--- Main ---

int maxiter = 8;

if(Mandel(@P.x, @P.y, @P.z, maxiter) < maxiter){
    @density = 0.0;
}
else {
    @density = 1.0;
}

AAND MY CONVERSION THAT DOES NOT WORK

function int Fractal(int Iterations, float Power, float Bailout, vector pos, vector z, float dr, float r){
	
		for (int i = 0; i < Iterations ; i++) {
		r = length(z);
		if (r>Bailout) break;

		// convert to polar coordinates
		float theta = acos(z.z/r);
		float phi = atan2(z.y,z.x);
		dr =  pow( r, Power-1.0)*Power*dr + 1.0;

		// scale and rotate the point
		float zr = pow( r,Power);
		theta = theta*Power;
		phi = phi*Power;

		// convert back to cartesian coordinates
		z = zr*vector(sin(theta)*cos(phi), sin(phi)*sin(theta), cos(theta));
		z+=pos;
		}
	return 0.5*log(r)*r/dr;
	}

	int Iterations = 10;
    float Power = 2.0;
    float Bailout = 20;
    vector pos = @P;
	vector z = @P;
	float dr = 1.0;
	float r = 0.0;
if(Fractal(Iterations,Power,Bailout,@P,@P,dr,r) < Iterations){
    @density = 0.0;
}
else {
    @density = 1.0;
}

 

Thanks in advance.

Cheers,

Scappin Matteo
www.machina-infinitum.com

[Librarian]

Nice Stuff --
https://www.machina-infinitum.com/vectron-formulas?fbclid=IwAR1Aihbcn5T2ngX5yAHUNDyJsO7peZYsOGW64g8exTq8YA5X5Rsq0A3sco0

 

why in vex? @machinainfinitum

This can HELP maybe
https://github.com/thi-ng/vexed-generation
https://github.com/jtomori/vft
https://www.sidefx.com/tutorials/vex-in-houdini-mandelbrot-and-mandelbulb/
https://vimeo.com/215581282

 

Edited October 22, 2020 by Librarian

[machinainfinitum]

Thanks  
I need to convert all my existing OSL fractals code to VEX.
Than I can mesh the VEX fractal and use it as dummy obj on top of Octane Vectron fractals

[varomix]

On 10/22/2020 at 10:28 AM, machinainfinitum said:

Thanks  
I need to convert all my existing OSL fractals code to VEX.
Than I can mesh the VEX fractal and use it as dummy obj on top of Octane Vectron fractals

Hi

not sure if you still care about this but I fixed your code

float fractal(int iterations; float power; float bailout; vector pos){

    float r = 0.0;
    float dr = 0.0;
    vector z = pos;
        
    for (int i = 0; i < iterations ; i++) {
            r = length(z);
            if (r>bailout) break;

            // convert to polar coordinates
            float theta = acos(z.z/r);
            float phi = atan2(z.y,z.x);
            dr =  pow( r, power-1.0)*power*dr + 1.0;

            // scale and rotate the point
            float zr = pow( r,power);
            theta = theta*power;
            phi = phi*power;

            // convert back to cartesian coordinates
            z = zr*set(sin(theta)*cos(phi), sin(phi)*sin(theta), cos(theta));
            z+=pos;
    }
        return 0.5*log(r)*r/dr;
}

int iterations = 5;
float power = 5.0;
float bailout = 20.0;
vector pos = @P;

float map = 0.0;
map = fractal(iterations, power, bailout, pos);

@surface = map;

 

[machinainfinitum]

14 minutes ago, varomix said:

Hi

not sure if you still care about this but I fixed your code

float fractal(int iterations; float power; float bailout; vector pos){

    float r = 0.0;
    float dr = 0.0;
    vector z = pos;
        
    for (int i = 0; i < iterations ; i++) {
            r = length(z);
            if (r>bailout) break;

            // convert to polar coordinates
            float theta = acos(z.z/r);
            float phi = atan2(z.y,z.x);
            dr =  pow( r, power-1.0)*power*dr + 1.0;

            // scale and rotate the point
            float zr = pow( r,power);
            theta = theta*power;
            phi = phi*power;

            // convert back to cartesian coordinates
            z = zr*set(sin(theta)*cos(phi), sin(phi)*sin(theta), cos(theta));
            z+=pos;
    }
        return 0.5*log(r)*r/dr;
}

int iterations = 5;
float power = 5.0;
float bailout = 20.0;
vector pos = @P;

float map = 0.0;
map = fractal(iterations, power, bailout, pos);

@surface = map;

 

This works perfectly ! Thanks so much!
Now I'll try to convert all the formulas I have

[varomix]

let me know if you need any help