new file mode 100644

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+( pseudo-random number generator )

+

+( devices )

+

+|00 @System     [ &vector $2 &wst      $1 &rst    $1 &pad   $4 &r      $2 &g      $2 &b    $2 &debug  $1 &halt $1 ]

+|20 @Screen     [ &vector $2 &width    $2 &height $2 &pad   $2 &x      $2 &y      $2 &addr $2 &pixel  $1 &sprite $1 ]

+|b0 @DateTime   [ &year   $2 &month    $1 &day    $1 &hour  $1 &minute $1 &second $1 &dotw $1 &doty   $2 &isdst $1 ]

+

+( variables )

+

+|0000

+

+( program )

+

+|0100 ( -> )

+	( init )

+	;on-frame .Screen/vector DEO2

+	( seed prng (must be nonzero) )

+	.DateTime/month DEI .DateTime/day DEI

+	#00 .DateTime/second #a0 SFT2 EOR2

+	#00 .DateTime/minute #40 SFT2 EOR2

+	.DateTime/hour EOR

+	ORAk ,&non-zero JCN INC2 &non-zero

+	;prng/seed STA2

+

+	( theme )

+	#0fe5 .System/r DEO2 

+	#0fc5 .System/g DEO2 

+	#0f25 .System/b DEO2

+	BRK

+

+@on-frame ( -> )

+	#c0

+	&loop

+		,draw-pixel JSR

+		INC

+		DUP ,&loop JCN

+	POP

+	BRK

+

+@draw-pixel

+	,prng JSR

+	#00 SWP .Screen/x DEO2

+	#00 SWP .Screen/y DEO2

+	#01 .Screen/pixel DEO

+	JMP2r

+

+@prng ( -- number* )

+	( returns the next number in the 65,535-long sequence,

+	  which is never zero but every other 16-bit number

+	  appears once before the sequence repeats )

+	,&seed LDR2

+	DUP2 #70 SFT2 EOR2

+	DUP2 #09 SFT2 EOR2

+	DUP2 #80 SFT2 EOR2

+	,&seed STR2k POP

+	JMP2r

+

+	&seed $2

+