From 20582afca51d54b21c8c347fceb55dc460ec5042 Mon Sep 17 00:00:00 2001
From: cuz <cuz@b7a2c559-68d2-44c3-8de9-860c34a00d81>
Date: Wed, 26 Nov 2003 21:17:29 +0000
Subject: [PATCH] Patches by Stefan Haubenthal

git-svn-id: svn://svn.cc65.org/cc65/trunk@2687 b7a2c559-68d2-44c3-8de9-860c34a00d81
---
 libsrc/apple2/apple2-280-192-6.s | 74 ++++++++++++++++++++++----------
 1 file changed, 51 insertions(+), 23 deletions(-)

diff --git a/libsrc/apple2/apple2-280-192-6.s b/libsrc/apple2/apple2-280-192-6.s
index 529321a20..7fa3dbc13 100644
--- a/libsrc/apple2/apple2-280-192-6.s
+++ b/libsrc/apple2/apple2-280-192-6.s
@@ -2,8 +2,7 @@
 ; Graphics driver for the 280x192x6 mode on the Apple II
 ;
 ; Stefan Haubenthal <polluks@sdf.lonestar.org>
-; Based on Stephen L. Judd's GRLIB code and
-; Maciej Witkowiak's circle routine
+; Based on Maciej Witkowiak's circle routine
 ;
 
 	.include	"zeropage.inc"
@@ -233,7 +232,7 @@ INIT:
 ; Switch into graphics mode
 
 	jsr	HGR
-	lda	MIXOFF
+	bit     MIXOFF
 
 ; Done, reset the error code
 
@@ -289,9 +288,9 @@ CLEAR		= HCLR
 SETVIEWPAGE:
 	tax
 	beq	@L1
-	lda	PG2ON
+	bit     PG2ON
 	rts
-@L1:	lda	PG2OFF
+@L1:	bit     PG2OFF
 	rts
 
 ; ------------------------------------------------------------------------
@@ -393,7 +392,7 @@ SETPIXEL:
 	ldy	X1+1
 	lda	Y1
 	jmp	HPLOT
-
+       
 ; ------------------------------------------------------------------------
 ; GETPIXEL: Read the color value of a pixel and return it in A/X. The
 ; coordinates passed to this function are never outside the visible screen
@@ -401,9 +400,38 @@ SETPIXEL:
 
 
 GETPIXEL:
-	lda	#TGI_ERR_INV_FUNC
-	sta	ERROR
-	rts
+       	ldx	X1
+       	ldy	X1+1
+       	lda	Y1
+       	jsr	HPOSN		; 1st pixel
+HBASL  	=	$26
+HMASK  	=	$30
+       	ldx	#0
+       	lda	(HBASL),y
+       	and	HMASK
+       	beq	@L1
+       	inx
+@L1:   	stx	tmp1
+       	lda	$E0		; which neighbour
+       	tax
+       	and	#$01
+       	bne	@odd
+       	asl	tmp1
+       	inx
+       	.byte	$24
+@odd:  	dex
+       	ldy	$E1
+       	lda	$E2
+       	jsr	HPOSN		; 2nd pixel
+       	ldx	#0
+       	lda	(HBASL),y
+       	and	HMASK
+       	beq	@L2
+       	inx
+@L2:   	txa
+       	ora	tmp1
+       	ldx	#0
+        rts
 
 ; ------------------------------------------------------------------------
 ; LINE: Draw a line from X1/Y1 to X2/Y2, where X1/Y1 = ptr1/ptr2 and
@@ -413,14 +441,14 @@ GETPIXEL:
 ;
 
 LINE:
-	ldx	X1
-	ldy	X1+1
-	lda	Y1
-	jsr	HPOSN
-	lda	X2
-	ldx	X2+1
-	ldy	Y2
-	jmp	HLIN
+       	ldx	X1
+       	ldy	X1+1
+       	lda	Y1
+       	jsr	HPOSN
+       	lda	X2
+       	ldx	X2+1
+       	ldy	Y2
+       	jmp	HLIN
 
 ; ------------------------------------------------------------------------
 ; BAR: Draw a filled rectangle with the corners X1/Y1, X2/Y2, where
@@ -428,12 +456,12 @@ LINE:
 ; Contrary to most other functions, the graphics kernel will sort and clip
 ; the coordinates before calling the driver, so on entry the following
 ; conditions are valid:
-;	X1 <= X2
-;	Y1 <= Y2
-;	(X1 >= 0) && (X1 < XRES)
-;	(X2 >= 0) && (X2 < XRES)
-;	(Y1 >= 0) && (Y1 < YRES)
-;	(Y2 >= 0) && (Y2 < YRES)
+;      	X1 <= X2
+;      	Y1 <= Y2
+;      	(X1 >= 0) && (X1 < XRES)
+;      	(X2 >= 0) && (X2 < XRES)
+;      	(Y1 >= 0) && (Y1 < YRES)
+;      	(Y2 >= 0) && (Y2 < YRES)
 ;
 ; Must set an error code: NO
 ;
-- 
2.39.5