MORTEVIELLE: Reimplemented the zzuul assembly routine in C code

3 files changed, 89 insertions, 0 deletions

diff --git a/engines/mortevielle/asm.cpp b/engines/mortevielle/asm.cpp
new file mode 100644
index 0000000000..2d057a38f9
--- /dev/null
+++ b/engines/mortevielle/asm.cpp
@@ -0,0 +1,52 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+/*
+ * This code is based on original Mortville Manor DOS source code
+ * Copyright (c) 1988-1989 Lankhor
+ */
+
+#include "common/scummsys.h"
+
+namespace Mortevielle {
+
+/**
+ * Decodes a number of 64 byte blocks
+ * @param pStart	Start of data
+ * @param count		Number of 64 byte blocks
+ */
+void zzuul(byte *pStart, int count) {
+	while (count-- > 0) {
+		for (int idx = 0; idx < 64; ++pStart, ++idx) {
+			uint16 v = ((*pStart - 0x80) << 1) + 0x80;
+
+			if (v & 0x8000)
+				*pStart = 0;
+			else if (v & 0xff00)
+				*pStart = 0xff;
+			else 
+				*pStart = (byte)v;
+		}
+	}
+}
+
+} // End of namespace Mortevielle
diff --git a/engines/mortevielle/asm.h b/engines/mortevielle/asm.h
new file mode 100644
index 0000000000..11793b3d46
--- /dev/null
+++ b/engines/mortevielle/asm.h
@@ -0,0 +1,36 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+/*
+ * This code is based on original Mortville Manor DOS source code
+ * Copyright (c) 1988-1989 Lankhor
+ */
+
+#ifndef MORTEVIELLE_ASM_H
+#define MORTEVIELLE_ASM_H
+
+namespace Mortevielle {
+
+extern void zzuul(byte *pStart, int count);
+
+} // End of namespace Mortevielle
+#endif
diff --git a/engines/mortevielle/module.mk b/engines/mortevielle/module.mk
index 50ec3f0197..21cb02587a 100644
--- a/engines/mortevielle/module.mk
+++ b/engines/mortevielle/module.mk
@@ -3,6 +3,7 @@ MODULE := engines/mortevielle
 MODULE_OBJS := \
 	actions.o \
 	alert.o \
+	asm.o \
 	boite.o \
 	detection.o \
 	disk.o \