From 8db6ec34182f838ed2058b5ae950b628eacff039 Mon Sep 17 00:00:00 2001
From: Vince Weaver <vince@deater.net>
Date: Wed, 18 Jul 2018 20:01:06 -0400
Subject: [PATCH] kfest: clear screen works

---
 kfest2018/raster.s | 58 +++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 52 insertions(+), 6 deletions(-)

diff --git a/kfest2018/raster.s b/kfest2018/raster.s
index 911236c9..b4746184 100644
--- a/kfest2018/raster.s
+++ b/kfest2018/raster.s
@@ -1,5 +1,8 @@
 ; Kansasfest HackFest Entry
 
+; Zero Page
+DRAW_PAGE	= $EE
+
 ; Soft Switches
 
 SET_GR	= $C050 ; Enable graphics
@@ -20,26 +23,69 @@ HOME	= $FC58				;; Clear the text screen
 	jsr	TEXT
 	jsr	HOME
 
+	lda	#0
+	sta	DRAW_PAGE
+
 	; GR part
 	bit	LORES
 	bit	SET_GR
 	bit	FULLGR
 
-	lda     #$55
-	ldx	#39
-border_loop:
-	sta	$5d0,X		; 38
+	; Clear Page0
+
+	lda	#$00
+	ldy	#46
+clear_page0_loop:
+	jsr	hline
+	dey
+	dey
+	bpl	clear_page0_loop
+
+	; Clear Page1
+
+
+
+
+	lda	#$55
+	ldy	#38
+	jsr	hline
+
 
-	dex
-	bpl	border_loop
 
 
 loop_forever:
 	jmp	loop_forever
 
 
+	;==================================
+	; HLINE
+	;==================================
+
+	; Color in A
+	; X has which line
+hline:
+	ldx	gr_offsets,y					; 4+
+	stx	hline_loop+1					; 4
+	ldx	gr_offsets+1,y					; 4+
+	stx	hline_loop+2					; 4
+	ldx	#39						; 2
+hline_loop:
+	sta	$5d0,X		; 38				; 5
+	dex							; 2
+	bpl	hline_loop					; 2nt/3
+	rts							; 6
+
+
+
+
 ;	H		E		L		L	O
 .byte	$D1,$00,$D1,$00, $D1,$01,$00, $D1,$00,$00, $D1,$00,$00, $D0,$01,$D0,$00
 .byte	$24,$04,$24,$00, $24,$20,$00, $24,$20,$00, $24,$20,$00, $04,$20,$04,$00
 .byte	$C9,$C0,$C9,$00, $C9,$C0,$00, $C9,$00,$00, $C9,$00,$00, $C9,$00,$C0,$00
 .byte	$06,$00,$06,$00, $06,$00,$00, $06,$00,$00, $06,$00,$00, $06,$00,$06,$00
+	; move these to zero page for slight speed increase?
+
+gr_offsets:
+	.word	$400,$480,$500,$580,$600,$680,$700,$780
+	.word	$428,$4a8,$528,$5a8,$628,$6a8,$728,$7a8
+	.word	$450,$4d0,$550,$5d0,$650,$6d0,$750,$7d0