Add a few utils. Start converting tabs to spaces.

src/nvmath/nvmath.h

@@ -7,6 +7,11 @@
 #include <nvcore/Debug.h>
 
 #include <math.h>
+#include <limits.h> // INT_MAX
+
+#if NV_OS_WIN32
+#include <float.h>
+#endif
 
 // Function linkage
 #if NVMATH_SHARED
@@ -92,10 +97,6 @@ inline float asinf_assert(const float f)
 #define asin asin_assert
 #define asinf asinf_assert
 
-#if NV_OS_WIN32
-#include <float.h>
-#endif
-
 namespace nv
 {
     inline float toRadian(float degree) { return degree * (PI / 180.0f); }
@@ -148,6 +149,12 @@ inline uint log2(uint i)
         return value;
     }
 
+    inline float log2f(float x)
+    {
+        nvCheck(x >= 0);
+        return logf(x) / logf(2.0f);
+    }
+
     inline float lerp(float f0, float f1, float t)
     {
         const float s = 1.0f - t;
@@ -159,6 +166,31 @@ inline float square(float f)
         return f * f;
     }
 
+    // @@ Float to int conversions to be optimized at some point. See:
+    // http://cbloomrants.blogspot.com/2009/01/01-17-09-float-to-int.html
+    // http://www.stereopsis.com/sree/fpu2006.html
+    // http://assemblyrequired.crashworks.org/2009/01/12/why-you-should-never-cast-floats-to-ints/
+    // http://chrishecker.com/Miscellaneous_Technical_Articles#Floating_Point
+    inline int iround(float f)
+    {
+        return int(f);
+    }
+
+    inline int ifloor(float f)
+    {
+        return int(floorf(f));
+    }
+
+    inline int iceil(float f)
+    {
+        return int(ceilf(f));
+    }
+
+    inline float frac(float f)
+    {
+        return f - floor(f);
+    }
+
 } // nv
 
 #endif // NV_MATH_H