From 3a8712202e6957df2382a310327873c7c2988085 Mon Sep 17 00:00:00 2001
From: ripsaw8080 <ripsaw8080@users.sourceforge.net>
Date: Tue, 29 Mar 2016 21:08:40 +0000
Subject: [PATCH] Add support for mode 8 row copy/fill. Fixes Tandy GW-BASIC
 interpreter SCREEN 3 scrolling/clearing.

Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@3973
---
 src/ints/int10_char.cpp | 22 +++++++++-------------
 1 file changed, 9 insertions(+), 13 deletions(-)

diff --git a/src/ints/int10_char.cpp b/src/ints/int10_char.cpp
index 6a610f31..478fa1da 100644
--- a/src/ints/int10_char.cpp
+++ b/src/ints/int10_char.cpp
@@ -54,14 +54,12 @@ static void CGA4_CopyRow(Bit8u cleft,Bit8u cright,Bit8u rold,Bit8u rnew,PhysPt b
 
 static void TANDY16_CopyRow(Bit8u cleft,Bit8u cright,Bit8u rold,Bit8u rnew,PhysPt base) {
 	Bit8u cheight = real_readb(BIOSMEM_SEG,BIOSMEM_CHAR_HEIGHT);
-	PhysPt dest=base+((CurMode->twidth*rnew)*(cheight/4)+cleft)*4;
-	PhysPt src=base+((CurMode->twidth*rold)*(cheight/4)+cleft)*4;	
+	Bit8u banks=CurMode->twidth/10;
+	PhysPt dest=base+((CurMode->twidth*rnew)*(cheight/banks)+cleft)*4;
+	PhysPt src=base+((CurMode->twidth*rold)*(cheight/banks)+cleft)*4;
 	Bitu copy=(cright-cleft)*4;Bitu nextline=CurMode->twidth*4;
-	for (Bitu i=0;i<cheight/4U;i++) {
-		MEM_BlockCopy(dest,src,copy);
-		MEM_BlockCopy(dest+8*1024,src+8*1024,copy);
-		MEM_BlockCopy(dest+16*1024,src+16*1024,copy);
-		MEM_BlockCopy(dest+24*1024,src+24*1024,copy);
+	for (Bitu i=0;i<cheight/banks;i++) {
+		for (Bitu b=0;b<banks;b++) MEM_BlockCopy(dest+b*8*1024,src+b*8*1024,copy);
 		dest+=nextline;src+=nextline;
 	}
 }
@@ -138,15 +136,13 @@ static void CGA4_FillRow(Bit8u cleft,Bit8u cright,Bit8u row,PhysPt base,Bit8u at
 
 static void TANDY16_FillRow(Bit8u cleft,Bit8u cright,Bit8u row,PhysPt base,Bit8u attr) {
 	Bit8u cheight = real_readb(BIOSMEM_SEG,BIOSMEM_CHAR_HEIGHT);
-	PhysPt dest=base+((CurMode->twidth*row)*(cheight/4)+cleft)*4;
+	Bit8u banks=CurMode->twidth/10;
+	PhysPt dest=base+((CurMode->twidth*row)*(cheight/banks)+cleft)*4;
 	Bitu copy=(cright-cleft)*4;Bitu nextline=CurMode->twidth*4;
 	attr=(attr & 0xf) | (attr & 0xf) << 4;
-	for (Bitu i=0;i<cheight/4U;i++) {
+	for (Bitu i=0;i<cheight/banks;i++) {
 		for (Bitu x=0;x<copy;x++) {
-			mem_writeb(dest+x,attr);
-			mem_writeb(dest+8*1024+x,attr);
-			mem_writeb(dest+16*1024+x,attr);
-			mem_writeb(dest+24*1024+x,attr);
+			for (Bitu b=0;b<banks;b++) mem_writeb(dest+b*8*1024+x,attr);
 		}
 		dest+=nextline;
 	}