From d1c1ecc89ff04d16a3f36209ce9d59a40a585f19 Mon Sep 17 00:00:00 2001
From: Aleteoryx <alyx@aleteoryx.me>
Date: Sat, 12 Apr 2025 18:57:55 -0400
Subject: [PATCH] lzw work

---
 gif.tal |  6 ++--
 lzw.tal | 93 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 mkfile  |  2 +-
 3 files changed, 97 insertions(+), 4 deletions(-)
 create mode 100644 lzw.tal

diff --git a/gif.tal b/gif.tal
index 15addaaf44b4cfadbe7f290906b0af0d3eeb2e7b..355851efb2fc1b6bf61c81f8179674c7a6ef1ad2 100644
--- a/gif.tal
+++ b/gif.tal
@@ -44,14 +44,14 @@
 	INC2 !puts
 
 
-@gif/chunk &magic $ff
+@Gif/chunk &magic $ff
 	&screen &wid $2 &hei $2 &pack $1 &bg $1 &aspect $1
 	&colortab $300
 	
-@gif/init ( -- )
+@Gif/init ( -- )
 	#06 /read
 	/magic-ok? ?{ ;errs/corrupt die }
-@gif/read ( len* -- )
+@Gif/read ( len* -- )
 	#00 SWP .File1/length DEO2
 	;/chunk .File1/read
 	JMP2r
diff --git a/lzw.tal b/lzw.tal
new file mode 100644
index 0000000000000000000000000000000000000000..192e2b4a8e37deff1e60068f401ab5100dbc6a0f
--- /dev/null
+++ b/lzw.tal
@@ -0,0 +1,93 @@
+|00 @System/vector $2 &expansion $2 &wst $1 &rst $1 &metadata $2 &r $2 &g $2 &b $2 &debug $1 &state $1
+|10 @Console/vector $2 &read $5 &type $1 &write $1 &error $1
+
+
+%dup3 ( a b c -- a b c a b c ) { ROTk ROT ROT }
+%dbg ( -- ) { [ LIT2 01 -System/debug ] DEO }
+
+|100
+@on-reset ( -> )
+	#ffff #00 LUT/insert POP2
+	#ffff LIT "A LUT/insert
+	LIT "B LUT/insert LIT "C LUT/insert POP2
+
+	#0002 LIT "C LUT/lookup
+	;putc-visitor LUT/visit
+	BRK
+
+@putc-visitor ( addr* sym -- )
+	.Console/write DEO POP2
+	JMP2r
+
+( @LUT )
+
+( visitor is a pointer to a routine of the form ( addr* sym -- ) )
+@LUT/visit ( addr* visitor* -- first-byte )
+	,/visitor STR2 /walk-up DUP ,/visitret STR
+	&visitloop
+		[ LIT2 &visitor $2 ] JSR2
+		,/buf-prev LDR2
+		INC2k ORA ?{ POP2 [ LIT &visitret $1 ] JMP2r }
+		/get STH POP2 ,/buf-parent LDR2 STHr ( addr* sym )
+		!/visitloop
+
+@LUT/cpybuf
+	&buf-prev $2 &buf-parent $2 &buf-sym $1
+
+@LUT/walk-up ( addr* -- addr* sym ) ( routine leaves root node metadata in /cpybuf )
+	#ffff SWP2 ( -1* node* )
+	&walkloop
+		DUP2 />getaddr DUP2 />setaddr
+		;/getext .System/expansion DEO2 ( load node info )
+		SWP2 ,/buf-prev STR2
+		;/setext .System/expansion DEO2 ( save child ptr )
+
+		,/buf-parent LDR2 ( node* new-node* )
+		INC2k ORA ?/walkloop
+	POP2 ,/buf-sym LDR JMP2r
+
+
+@LUT/insert ( parent* sym -- addr* )
+	,/size LDR2 DUP2 />setaddr
+	INC2k ,/size STR2 STH2
+
+	,/buf-sym STR ,/buf-parent STR2
+	;/setext .System/expansion DEO2
+	STH2r JMP2r
+
+@LUT/get ( addr* -- parent* sym )
+	/>getaddr
+	;/getext .System/expansion DEO2
+
+	,/buf-parent LDR2 ,/buf-sym LDR
+	JMP2r
+
+@LUT/lookup ( parent* sym -- addr* )
+	[ LIT2r 0000 ]
+	&lookuploop
+		dup3
+		STH2rk [ LIT2 &size 0000 ]
+		LTH2 ?{ POP2r POP2 POP2 POP2 #ffff JMP2r }
+		STH2rk /get ( parent1* sym1  parent2* sym2 )
+		STH ROT STH NEQ2 NEQr STHr ORA ( parent1 != parent2 || sym1 != sym2 )
+		INC2r ?/lookuploop
+	POP2 POP STH2r #0001 SUB2 JMP2r
+
+@LUT/>getaddr ( addr* -- )
+	DUP2 #3334 DIV2 INC2
+	,/getbank STR2
+	#0005 MUL2
+	,/getaddr STR2
+	JMP2r
+
+@LUT/>setaddr ( addr* -- )
+	DUP2 #3334 DIV2 INC2
+	,/setbank STR2
+	#0005 MUL2
+	,/setaddr STR2
+	JMP2r
+
+@LUT/setext
+	01  0005  0000 =/cpybuf  &setbank $2 &setaddr $2
+@LUT/getext
+	01  0005  &getbank $2 &getaddr $2  0000 =/cpybuf
diff --git a/mkfile b/mkfile
index e6f8e85c58f82eaad8ba80c7ae83e67fa53da9a6..d2080606486647163dfc947f3100d4da961204bc 100644
--- a/mkfile
+++ b/mkfile
@@ -2,7 +2,7 @@ roms=\
 	arvelie.rom\
 	nanpa.rom\
 	bfc.rom\
-	gif.rom
+	lzw.rom
 
 all:VQ: $roms