vx = sin(0.8 * f) * (VIDEOX * 0.5) - (VIDEOX * 0.5) + state;
    vy = cos(1.2 * f) * (VIDEOY * 0.5) - (VIDEOY * 0.5) + state;

    /* draw plasma */
    for(y = 0; y < VIDEOY; y++)
    {
      for(x = 0; x < VIDEOX; x++)
      {
        xx = vx;
        xx += x;
        xx *= xx;

        yy = vy;
        yy += y;
        yy *= yy;

        c1 = x;
        c1 *= 0.02;
        c1 += f;
        c1 += y;
        c1 *= 0.005;
        c1 = sin(c1);

        c2 = xx;
        c2 += yy;
        c2 = sqrt(c2);
        c2 *= 0.02;
        c2 = sin(c2);

        c3 = c1;
        c3 += c2;
        c3 *= 0.5;
        c3 += 1;
        c3 *= 127;

        res = ceil(c3);

        ppixel(screen, x, y, r[res], g[res], b[res]);
      }
    }