From 503b95acc0117f2900dc7a4e1ada306f6461270a Mon Sep 17 00:00:00 2001
From: Lukas Krickl <lukas@krickl.dev>
Date: Wed, 22 Mar 2023 06:26:43 +0100
Subject: [PATCH] WutFace bug

---
 main.asm | 62 ++++++++++++++++++++++++++------------------------------
 1 file changed, 29 insertions(+), 33 deletions(-)

diff --git a/main.asm b/main.asm
index 44549d3..d634147 100644
--- a/main.asm
+++ b/main.asm
@@ -133,21 +133,37 @@ Player1UpNotPressed
 
 	; Do 192 scanlines of colour-changing (our picture)
 	ldx 0
+Picture
+	stx COLUBK ; ranbow effect on background
+
+PlayFieldStart
 	; set up PF to display a wall around the game field
 	lda #%11111111
 	sta PF0
 	sta PF1
 	sta PF2
-Picture
-	stx COLUBK ; ranbow effect on background
+Top8LinesWall
+	sta WSYNC
+	inx
+	cpx #8 ; line 8?
+	bne Top8LinesWall ; No? Another loop
+
+	; now we change the lines
+	lda #%00010000 ; PF0 is mirrored <--- direction, low 4 bits ignored
+	sta PF0
+	lda #0
+	sta PF1
+	sta PF2
 
+	; again, we don't bother writing PF0-PF2 every scanline - they never change!
+	ldy #0 ; load y with 0, we use y to count sprite tables
+MiddleLinesWall
 	lda #1 ; load an odd number into a
 	and FRAMECOUNT ; and it with framecount to see if even or odd frame count
-	; only do sprites on odd frames 0 == even 1 == odd
+	; only do sprites on even frames 0 == even 1 == odd
 	cmp NULL
 	beq SpriteDone
-
-	; sprite stuff 192 scanlines
+	; sprite stuff
 SpriteStart
 	cpx SPR1Y
 	bcc SpriteReset
@@ -162,7 +178,7 @@ SpriteStart
 	sbc #15
 	bcs .divideby15
 
-	sta RESP0
+	sta RESP0,x
 
 	lda TurtleSprite,y
 	sta GRP0 ; modify sprite 0 shape
@@ -174,27 +190,7 @@ SpriteReset
 	lda #0
 	sta GRP0
 SpriteDone
-	sta WSYNC
-	inx
-	cpx #192
-	bne SpriteStart
-
-Top8LinesWall
-	sta WSYNC
-	inx
-	cpx #8 ; line 8?
-	bne Top8LinesWall ; No? Another loop
 
-	; now we change the lines
-	lda #%00010000 ; PF0 is mirrored <--- direction, low 4 bits ignored
-	sta PF0
-	lda #0
-	sta PF1
-	sta PF2
-
-	; again, we don't bother writing PF0-PF2 every scanline - they never change!
-	ldy #0 ; load y with 0, we use y to count sprite tables
-MiddleLinesWall
 	; push y to save for later
 	sta WSYNC
 
@@ -220,20 +216,20 @@ Bottom8LinesWall
 	inx
 	cpx #192
 	bne Bottom8LinesWall
-
+PlayFieldDone
 	; ---------------
 
-	lda #%01000010
-	sta VBLANK ; end of screen - start blanking
-
-
-
-	; 30 scanlines of overscan
+	; clear playfield first
 	lda #0
 	sta PF0
 	sta PF1
 	sta PF2
 
+	lda #%01000010
+	sta VBLANK ; end of screen - start blanking
+
+	; 30 scanlines of overscan
+
 	ldx #0
 Overscan
 	sta WSYNC
-- 
2.30.2