Added a utility method to provide multiple FTO random-state scrambles…

…, which is must faster than generating multiple single scrambles.

README.md

@@ -130,9 +130,15 @@ In `clockScrambler` module:
 ### FTO (Face-turning octahedron)
 In `ftoScrambler` module:
 
-- `get_random_state_scramble()`        random-state scramble (note: this is slow-ish, ~10s per scramble)
+- `get_random_state_scramble()`        random-state scramble (note: this takes ~10s per scramble)
+- `get_multiple_random_state_scrambles(n)`  returns a list of `n` random-state scrambles
 - `get_random_moves_scramble(n=30)`    random-moves scramble of length `n`
 
+If you need multiple random-state scrambles, it's much faster to use `get_multiple_random_state_scrambles` than
+calling `get_random_state_scramble` multiple times; the former takes the usual ~10s for the first scramble but then
+the remaining scrambles are much faster (less than 1s per scramble). This is due to how the underlying FTO scrambler
+generates background data during the first scramble which is used to speed up subsequent scrambles.
+
 ### Big cubes
 In `bigCubesScrambler` module:
 

pyTwistyScrambler/ftoScrambler.py

@@ -10,6 +10,12 @@ def get_random_state_scramble():
     return _FTO_SCRAMBLER.call("generate_random_state_scramble")
 
 
+def get_multiple_random_state_scrambles(n):
+    """ Gets `n` random-state scrambles for FTO (face-turning octahedron). """
+    scrambles = _FTO_SCRAMBLER.call("generate_multiple_random_state_scrambles", n)
+    return [s.strip() for s in scrambles]
+
+
 @trim
 def get_random_moves_scramble(scramble_length = 30):
     """ Returns a random-moves scramble of length `scramble_length` for FTO. """

pyTwistyScrambler/js_resources/fto.js

@@ -866,6 +866,16 @@ function simplify_move_sequence(move_sequence, make_noise=false)
 	return simplified;
 }
 
+function generate_multiple_random_state_scrambles(n)
+{
+    var scrambles = [];
+    for (var i = 0; i < n; i++) {
+      scrambles.push(generate_random_state_scramble());
+    }
+
+    return scrambles;
+}
+
 function generate_random_state_scramble()
 {
 	return stringify_move_sequence(invert_move_sequence(solve(random_state())), true);