From 7740856c39cc7ecbc4040007479901dc4f1b1341 Mon Sep 17 00:00:00 2001
From: Vince Weaver <vince@deater.net>
Date: Sun, 7 Oct 2018 15:41:27 -0400
Subject: [PATCH] space_bars: working on splitting screen

---
 space_bars/game.s         | 43 ++++++++++++++++-----
 space_bars/screen_split.s | 80 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 113 insertions(+), 10 deletions(-)
 create mode 100644 space_bars/screen_split.s

diff --git a/space_bars/game.s b/space_bars/game.s
index 1430f348..ee2d185f 100644
--- a/space_bars/game.s
+++ b/space_bars/game.s
@@ -211,17 +211,36 @@ sbloopD:dex								; 2
 
 
 
+sb_mixed:
+	nop		;kill 6 cycles (room for rts)	; 2
+	nop						; 2
+	ldy	#144					; 2
+
 sb_mixed_loop:
+	nop
+	nop
+	nop
+	nop
+	jsr	split_4					; 6+46
+	dey						; 2
+	bne	sb_mixed_loop				; 3
+
+							; -1
+
+							; so need delay 5
+							; in vblank
+
+
 	; delay 144*65 =  9360
 
 	; Try X=37 Y=49 cycles=9360
 
-	ldy	#49							; 2
-sbloopE:ldx	#37							; 2
-sbloopF:dex								; 2
-	bne	sbloopF							; 2nt/3
-	dey								; 2
-	bne	sbloopE							; 2nt/3
+;	ldy	#49							; 2
+;sbloopE:ldx	#37							; 2
+;sbloopF:dex								; 2
+;	bne	sbloopF							; 2nt/3
+;	dey								; 2
+;	bne	sbloopE							; 2nt/3
 
 
 
@@ -230,14 +249,17 @@ sbloopF:dex								; 2
 	;======================================================
 
 	; do_nothing should be      4550
+	;			     - 5 from above
 	;			     -10 keypress
 	;			===========
-	;			    4540
+	;			    4535
 
-	; Try X=9 Y=89 cycles=4540
+	; Try X=40 Y=22 cycles=4533 R2
 
-	ldy	#89							; 2
-sbloop1:ldx	#9							; 2
+	nop
+
+	ldy	#22							; 2
+sbloop1:ldx	#40							; 2
 sbloop2:dex								; 2
 	bne	sbloop2							; 2nt/3
 	dey								; 2
@@ -260,3 +282,4 @@ background_hgr:
 .incbin "SB_BACKGROUNDC.BIN.lz4",11
 background_hgr_end:
 
+.include "screen_split.s"
diff --git a/space_bars/screen_split.s b/space_bars/screen_split.s
new file mode 100644
index 00000000..6a27769c
--- /dev/null
+++ b/space_bars/screen_split.s
@@ -0,0 +1,80 @@
+; how quickly can we call this?
+; jump table, assuming size to split is in Y?
+
+; Autogenerate?  As we want both HGR/TXT and HGR/GR versions?
+
+
+; 4  NnNnNnNnNnNnNnNnBBBBbbbbNnNnNnNnNnNnNnNnRrrrrr
+; 8  NnNnNnNnNnNnNnBBBBNnNnbbbbNnNnNnNnNnNnNnRrrrrr
+; 12 NnNnNnNnNnNnBBBBNnNnNnNnbbbbNnNnNnNnNnNnRrrrrr
+; 16 NnNnNnNnNnBBBBNnNnNnNnNnNnbbbbNnNnNnNnNnRrrrrr
+; 20 NnNnNnNnBBBBNnNnNnNnNnNnNnNnbbbbNnNnNnNnRrrrrr
+; 24 NnNnNnBBBBNnNnNnNnNnNnNnNnNnNnbbbbNnNnNnRrrrrr
+; 28 NnNnBBBBNnNnNnNnNnNnNnNnNnNnNnNnbbbbNnNnRrrrrr
+; 32 NnBBBBNnNnNnNnNnNnNnNnNnNnNnNnNnNnbbbbNnRrrrrr
+; 36 BBBBNnNnNnNnNnNnNnNnNnNnNnNnNnNnNnNnbbbbRrrrrr
+
+
+
+
+split_4:
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	bit	LORES
+	bit	HIRES
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	rts
+
+split_8:
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	bit	LORES
+	nop
+	nop
+	bit	HIRES
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	rts
+
+
+
+	;       6       4       25+16+8+16  NNNNNNNN
+        ;       7       6       25+15+10+15 LNNNNNN
+        ;       8       8       25+14+12+14 NNNNNNN
+        ;       9       10      25+13+14+13 LNNNNN
+        ;       10      12      25+12+16+12
+        ;       11      14      25+11+18+11
+        ;       12      16      25+10+20+10
+        ;       13      18      25+09+22+09
+        ;       14      20      25+08+24+08
+        ;       15      22      25+07+26+07
+        ;       16      24      25+06+28+06
+        ;       17      26      25+05+30+05
+        ;       18      28      25+04+32+04
+        ;       19      30      25+03+34+03
+        ;       20      32      25+02+36+02
+        ;       21      34      25+01+38+01
+