ILLUSIONS: More work on the Camera class

- Add fixed point code (untested and probably wrong)

1 files changed, 62 insertions, 0 deletions

diff --git a/engines/illusions/fixedpoint.cpp b/engines/illusions/fixedpoint.cpp
new file mode 100644
index 0000000000..ee3818d10a
--- /dev/null
+++ b/engines/illusions/fixedpoint.cpp
@@ -0,0 +1,62 @@
+/* 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.
+ *
+ */
+
+#include "illusions/illusions.h"
+#include "illusions/fixedpoint.h"
+
+namespace Illusions {
+
+FP16 floatToFixed(float value) {
+	return value * 65536.0;
+}
+
+float fixedToFloat(FP16 value) {
+	return value / 65536.0;
+}
+
+FP16 fixedMul(FP16 a, FP16 b) {
+	// CHECKME Not sure if this correct
+	return (a * b) >> 16;
+}
+
+FP16 fixedDiv(FP16 a, FP16 b) {
+	// CHECKME Not sure if this correct
+	return (a << 16) / b;
+}
+
+int fixedTrunc(FP16 value) {
+	// CHECKME Not sure if this correct
+	int result = value >> 16;
+	if ((value & 0xFFFF) >= 0x8000)
+		++result;
+	return result;
+}
+
+FP16 fixedDistance(FP16 x1, FP16 y1, FP16 x2, FP16 y2) {
+	float xd = ABS(fixedToFloat(x1) - fixedToFloat(x2));
+	float yd = ABS(fixedToFloat(y1) - fixedToFloat(y2));
+	if (xd != 0.0 || yd != 0.0)
+		return floatToFixed(sqrt(xd * xd + yd * yd));
+	return 0;
+}
+
+} // End of namespace Illusions