Merge branch 'master'

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diff --git a/common/math.h b/common/math.h
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+/* 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.
+ *
+ */
+
+// Based on eos' math code
+
+#ifndef COMMON_MATH_H
+#define COMMON_MATH_H
+
+#include "common/scummsys.h"
+#ifdef _MSC_VER
+// HACK:
+// intrin.h on MSVC includes setjmp.h, which will fail compiling due to our
+// forbidden symbol colde. Since we also can not assure that defining
+// FORBIDDEN_SYMBOL_EXCEPTION_setjmp and FORBIDDEN_SYMBOL_EXCEPTION_longjmp
+// will actually allow the symbols, since forbidden.h might be included
+// earlier already we need to undefine them here...
+#undef setjmp
+#undef longjmp
+#include <intrin.h>
+// ...and redefine them here so no code can actually use it.
+// This could be resolved by including intrin.h on MSVC in scummsys.h before
+// the forbidden.h include. This might make sense, in case we use MSVC
+// extensions like _BitScanReverse in more places. But for now this hack should
+// be ok...
+#ifndef FORBIDDEN_SYMBOL_EXCEPTION_setjmp
+#undef setjmp
+#define setjmp(a)	FORBIDDEN_SYMBOL_REPLACEMENT
+#endif
+
+#ifndef FORBIDDEN_SYMBOL_EXCEPTION_longjmp
+#undef longjmp
+#define longjmp(a,b)	FORBIDDEN_SYMBOL_REPLACEMENT
+#endif
+#endif
+
+#ifndef M_SQRT1_2
+	#define M_SQRT1_2 0.70710678118654752440 /* 1/sqrt(2) */
+#endif
+
+#ifndef M_PI
+	#define M_PI 3.14159265358979323846
+#endif
+
+#ifndef FLT_MIN
+	#define FLT_MIN 1E-37
+#endif
+
+#ifndef FLT_MAX
+	#define FLT_MAX 1E+37
+#endif
+
+namespace Common {
+
+/** A complex number. */
+struct Complex {
+	float re, im;
+};
+
+#if defined(__GNUC__) && (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4))
+inline int intLog2(uint32 v) {
+	// This is a slightly optimized implementation of log2 for natural numbers
+	// targeting gcc. It also saves some binary size over our fallback
+	// implementation, since it does not need any table.
+	if (v == 0)
+		return -1;
+	else
+		// This is really "sizeof(unsigned int) * CHAR_BIT - 1" but using 8
+		// instead of CHAR_BIT is sane enough and it saves us from including
+		// limits.h
+		return (sizeof(unsigned int) * 8 - 1) - __builtin_clz(v);
+}
+#elif defined(_MSC_VER)
+inline int intLog2(uint32 v) {
+	unsigned long result = 0;
+	unsigned char nonZero = _BitScanReverse(&result, v);
+	// _BitScanReverse stores the position of the MSB set in case its result
+	// is non zero, thus we can just return it as is.
+	return nonZero ? result : -1;
+}
+#else
+// See http://graphics.stanford.edu/~seander/bithacks.html#IntegerLogLookup
+static const char LogTable256[256] = {
+#define LT(n) n, n, n, n, n, n, n, n, n, n, n, n, n, n, n, n
+	-1, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3,
+	LT(4), LT(5), LT(5), LT(6), LT(6), LT(6), LT(6),
+	LT(7), LT(7), LT(7), LT(7), LT(7), LT(7), LT(7), LT(7)
+};
+
+inline int intLog2(uint32 v) {
+	register uint32 t, tt;
+
+	if ((tt = v >> 16))
+		return (t = tt >> 8) ? 24 + LogTable256[t] : 16 + LogTable256[tt];
+	else
+		return (t =  v >> 8) ?  8 + LogTable256[t] : LogTable256[v];
+}
+#endif
+
+inline float rad2deg(float rad) {
+	return rad * 180.0 / M_PI;
+}
+
+inline float deg2rad(float deg) {
+	return deg * M_PI / 180.0;
+}
+
+} // End of namespace Common
+
+#endif // COMMON_MATH_H