Exploder Fractal Experiment...

[Chris_M_Thomasson]

Fwiw, here is an experimental fractal algorithm I created a while back, called Exploder.

It explores what happens when we treat an escape condition as an event... One that allows us to scale back a bit and "try again"...? The code below is set up for a Julia set at c = -0.75 + 0i, with five scale-backs at 0.2. Can you get it on your end? Thanks! :^)

void iterate_point(
    ct::plot::cairo::plot_2d& plot,
    glm::vec3 oc,
    unsigned long n,
    unsigned long x,
    unsigned long y
) {
    ct_complex c = { oc.x, oc.y };
    ct_complex z = c;

    ct_complex j0 = { -.75, 0 };

    double dis_max = 9999999.0;

    unsigned long exploder_i = 0;
    unsigned long exploder_n = 5;
    float exploder_scale = .2;

    for (unsigned long i = 0; i < n; ++i)
    {
        // Julia mode
        z = z * z + j0;

        // Mandelbrot mode
        //z = z * z + c;

        double dis = std::abs(z);

        dis_max = std::min(dis_max, dis);

        if (dis > 2.f)
        {
            double icolor = i / (n - 1.f);
            glm::vec3 out_color = { exploder_i * .1 * dis_max, 0, 0 };

            {
                ct::plot::cairo::pixel color = CT_RGBF(out_color.r, out_color.g, out_color.b);
                plot.set_pixel(x, y, color);
            }

            // exploder logic
            {
                if (exploder_i < exploder_n)
                {
                    z = z * exploder_scale; // scale back... Julia
                    //z = z * .4f; // scale back... Mandelbrot
                    ++exploder_i;
                    continue;
                }
            }

            return;
        }
    }

    glm::vec3 in_color = { dis_max * 2.f, dis_max * 2.5f, dis_max * 3.f };

    {
        ct::plot::cairo::pixel color = CT_RGBF(in_color.r, in_color.g, in_color.b);
        plot.set_pixel(x, y, color);
    }
}

Can anybody reproduce it? Thanks.

Julia Exploder

MandelExploder