From 2a5eaa1ea2372e00955b3c65d82e5077a8b92546 Mon Sep 17 00:00:00 2001
From: alpine9000 <alex.g.brown@gmail.com>
Date: Fri, 1 Apr 2016 16:35:02 +1100
Subject: [PATCH] Simplifying char blit

---
 025.scroll_text/blitchar.s    | 17 ++++++-----------
 025.scroll_text/scroll_text.s | 10 ++++++----
 2 files changed, 12 insertions(+), 15 deletions(-)

diff --git a/025.scroll_text/blitchar.s b/025.scroll_text/blitchar.s
index 4e0e0f5..b8b51eb 100644
--- a/025.scroll_text/blitchar.s
+++ b/025.scroll_text/blitchar.s
@@ -22,7 +22,6 @@ BlitChar8:
 	movem.l	d0-d3/a0-a2,-(sp)
         mulu.w	#BITPLANE_WIDTH_BYTES*SCREEN_BIT_DEPTH,d1		; ypos bytes
 	lea	font(pc),a1						; font pointer
-	lea	fontMask,a2						; font mask pointer
 
 	sub.w	#'!',d2		; index = char - '!'
 	move.w	d2,d3	
@@ -31,16 +30,10 @@ BlitChar8:
 	add.l	#1,d3		; while we have a weird font image, '!' starts on second line
 	mulu.w	#FONTMAP_WIDTH_BYTES*SCREEN_BIT_DEPTH*FONT_HEIGHT,d3 	; d3 *= #FONTMAP_WIDTH_BYTES*SCREEN_BIT_DEPTH*FONT_HEIGHT
 
-	if MASKED_FONT==1
-	add.w	d3,a2		; add y offset in lines to fontMask address
-	add.l	d2,a2		; add offset into mask
-	endif
 	add.l	#(FONT_HEIGHT*SCREEN_BIT_DEPTH*FONTMAP_WIDTH_BYTES)-FONTMAP_WIDTH_BYTES+0,a1 ; last word - descending mode
 	
 	add.w	d3,a1		; add y offset in lines to font address
 	add.w	d2,a1		; add offset into font
-	add.l	#(FONT_HEIGHT*SCREEN_BIT_DEPTH*FONTMAP_WIDTH_BYTES)-FONTMAP_WIDTH_BYTES+0,a2 ; last word - descending mode
-		
 	lsr.w	#3,d0		; d0 = xpos bytes	
 
 	add.l 	d0,a0		; dest += XPOS_BYTES
@@ -72,11 +65,13 @@ BlitChar8:
 .continue:
 
 	
-	if MASKED_FONT==1
-	move.l 	a2,BLTAPTH(a6)				; mask bitplane
-	endif
-
 	move.l 	a1,BLTBPTH(a6)				; source bitplane		
+
+	if MASKED_FONT==1
+	add.l	#fontMask-font,a1
+	move.l 	a1,BLTAPTH(a6)				; mask bitplane
+	endif
+	
 	
 	move.l 	a0,BLTCPTH(a6) 				; background top left corner
 	move.l 	a0,BLTDPTH(a6) 				; destination top left corner
diff --git a/025.scroll_text/scroll_text.s b/025.scroll_text/scroll_text.s
index 60fdc23..baa8127 100644
--- a/025.scroll_text/scroll_text.s
+++ b/025.scroll_text/scroll_text.s
@@ -4,6 +4,8 @@
 	xdef	onscreen
 	xdef	offscreen
 	xdef	copperListBplPtr
+
+Y_POS	equ	16
 	
 byteMap:
 	dc.l	Entry
@@ -43,8 +45,8 @@ MainLoop:
 	if 0
 	;; test
 	move.b	#'B',d2
-	move.l	#32,d0			; xpos
-	move.l	#100,d1		  	; ypos
+	move.l	#16,d0			; xpos
+	move.l	#0,d1		  	; ypos
 	move.l	onscreen,a0
 	jsr	BlitChar8		
 	bra	MainLoop
@@ -62,14 +64,14 @@ MainLoop:
 .moreText:	
 	move.b	(a3)+,d2
 	move.l	#BITPLANE_WIDTH-16,d0	; xpos
-	move.l	#16,d1		  	; ypos
+	move.l	#Y_POS,d1		; ypos
 	move.l	onscreen,a0
 	jsr	BlitChar8
 	move.l	#0,shiftcounter
 .shift:
 	move.l	onscreen,a0
 	move.l	#FONT_HEIGHT,d1
-	move.l	#16,d2
+	move.l	#Y_POS,d2
 	jsr	BlitScroll
 	add.l	#1,shiftcounter