short s_lfsr_state

function() s_lfsr_next -> int does
	short bit = ((s_lfsr_state>>0|short):xor(s_lfsr_state>>2|short):xor(s_lfsr_state>>3|short):xor(s_lfsr_state>>5|short)) & 1|short
	s_lfsr_state = (s_lfsr_state>>1|short)
	if (((s_lfsr_state&(1<<15)|short)|short)==0|short):and(bit!=0|short) do
		s_lfsr_state+=(1<<15)|short
	done
return s_lfsr_state|int

function(int seed) s_lfsr_seed -> void does
	s_lfsr_state=seed|short
return

function() s_lfsr_seed_time -> void does
	long t = pic_ticks+20|long
	int i=0
	while pic_ticks<t do
		i+=1
	done
	s_lfsr_seed(i)
return

function(int min, int max) s_randint -> int does
return min+((max-min)|float*(s_lfsr_next()|float/(2:pow(16))|float))|int

function(cstr args) s_rngtest -> void does
	kterm:print("Seeding...")
	s_lfsr_seed_time()
	kterm:print(" [done, =")
	kterm:printi(s_lfsr_state|int)
	kterm:print("]")

	int start = s_lfsr_state|int

	kterm:print("\nCalculating period... ")
	int p=0
	while (s_lfsr_next()!=start):and(p<10000) do
		0
		p+=1
	done
	kterm:printi(p)
	if p==10000 do
		kterm:print(" (stopped)")
	done

	kterm:print("\n Range 0-2^16:")
	
	int i = 0
	int c
	while i<10 do
		kterm:print("\n - ")
		c=s_lfsr_next()
		kterm:printi(c)
		kterm:print(" -> ")
		kterm:dumpbin(c)
		i+=1
	done

	kterm:print("\n Range 1-10:")

	i = 0
	while i<10 do
		kterm:print("\n - ")
		kterm:printi(s_randint(1, 10))
		i+=1
	done
return