Initial revision

git-svn-id: svn://svn.icculus.org/blackshades/trunk@2 5198baeb-e213-0410-be47-fc2ff85ca46f

1 files changed, 21 insertions, 0 deletions

diff --git a/Source/Maths.cpp b/Source/Maths.cpp
new file mode 100644
index 0000000..f8f2664
--- /dev/null
+++ b/Source/Maths.cpp
@@ -0,0 +1,21 @@
+/**> HEADER FILES <**/
+#include "Maths.h"
+
+double fast_sqrt (register double arg)
+{	
+	// Can replace with slower return std::sqrt(arg);
+	register double result;
+
+	if (arg == 0.0) return 0.0;
+	
+	asm {
+		frsqrte		result,arg			// Calculate Square root
+	}	
+	
+	// Newton Rhapson iterations.
+	result = result + 0.5 * result * (1.0 - arg * result * result);
+	result = result + 0.5 * result * (1.0 - arg * result * result);
+	
+	return result * arg;
+}
+