fractal { // Set region margins to left=-3.0, bottom=-1.5, right=0.0, top=1.5 // Declare state vector as [x,n] where x and n are built-in variables orbit [<-3.0,-1.5>,<0.0,1.5>] [x,n] { // Iterate for n from 0 to 200 stopping when mod2(x) > 4 loop [0, 200] (mod2(x) > 4) { // Declare orbit equation where x is a state variable and w is current point of region x = x * x + w; } } // Set background color to alpha=1, red=1, green=1, blue=1 color [(1,1,1,1)] { // Apply rule when n > 0 and set opacity to 1.0 rule (n > 0) [1.0] { // Set color components to alpha=1, red=0, green=0, blue=0 1,0,0,0 } } }