Merge branch 'vanilla_0.5.0.1' into jogamp_0.5.0.1

Conflicts:
	LibOVR/Include/OVR_CAPI_0_5_0.h
	LibOVR/Src/CAPI/CAPI_HMDState.cpp
	LibOVR/Src/Displays/OVR_Win32_Dxgi_Display.h
	LibOVR/Src/Kernel/OVR_System.cpp
	LibOVR/Src/OVR_CAPI.cpp
	LibOVR/Src/OVR_Profile.cpp
	LibOVRKernel/Src/Kernel/OVR_ThreadsWinAPI.cpp
	LibOVRKernel/Src/Kernel/OVR_Types.h

1 files changed, 201 insertions, 0 deletions

diff --git a/LibOVRKernel/Src/Kernel/OVR_Rand.h b/LibOVRKernel/Src/Kernel/OVR_Rand.h
new file mode 100644
index 0000000..14897c0
--- /dev/null
+++ b/LibOVRKernel/Src/Kernel/OVR_Rand.h
@@ -0,0 +1,201 @@
+/************************************************************************************
+
+PublicHeader:   OVR_Kernel.h
+Filename    :   OVR_Rand.h
+Content     :   Random number generator
+Created     :   Aug 28, 2014
+Author      :   Chris Taylor
+
+Copyright   :   Copyright 2014 Oculus VR, Inc. All Rights reserved.
+
+Licensed under the Oculus VR Rift SDK License Version 3.2 (the "License"); 
+you may not use the Oculus VR Rift SDK except in compliance with the License, 
+which is provided at the time of installation or download, or which 
+otherwise accompanies this software in either electronic or hard copy form.
+
+You may obtain a copy of the License at
+
+http://www.oculusvr.com/licenses/LICENSE-3.2 
+
+Unless required by applicable law or agreed to in writing, the Oculus VR SDK 
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+************************************************************************************/
+
+#ifndef OVR_Rand_h
+#define OVR_Rand_h
+
+#include "OVR_Types.h"
+#include <math.h>
+
+namespace OVR {
+
+
+/*
+ This is designed to generate up to 2^^32 numbers per seed.
+
+ Its period is about 2^^126 and passes all BigCrush tests.
+ It is the fastest simple generator that passes all tests.
+
+ It has a few advantages over the stdlib RNG, including that
+ all bits of the output are equally good in quality.
+ Furthermore, the input seeds are hashed to avoid linear
+ relationships between the input seeds and the low bits of
+ the first few outputs.
+*/
+class RandomNumberGenerator
+{
+protected:
+    uint64_t Rx;
+    uint64_t Ry;
+    double NextRandN;
+    bool Seeded;
+    bool HaveRandN;
+
+public:
+    RandomNumberGenerator() :
+        Seeded(false),
+        HaveRandN(false)
+        // Other members left uninitialized
+    {
+    }
+
+    bool IsSeeded() const
+    {
+        return Seeded;
+    }
+
+    // Seed with a random state
+    void SeedRandom();
+
+    // Start with a specific seed
+    void Seed(uint32_t x, uint32_t y);
+
+    // Returns an unsigned uint32_t uniformly distributed in interval [0..2^32-1]
+    OVR_FORCE_INLINE uint32_t Next()
+    {
+        // If it is not Seeded yet,
+        if (!IsSeeded())
+        {
+            SeedRandom();
+        }
+
+        // Sum of two long-period MWC generators
+        Rx = (uint64_t)0xfffd21a7 * (uint32_t)Rx + (uint32_t)(Rx >> 32);
+        Ry = (uint64_t)0xfffd1361 * (uint32_t)Ry + (uint32_t)(Ry >> 32);
+        return (((uint32_t)Rx << 7) | ((uint32_t)Rx >> (32 - 7))) + (uint32_t)Ry; // ROL(x, 7) + y
+    }
+
+    // The following functions are inspired by the Matlab functions rand(), randi(), and randn()
+
+    // Uniform distribution over open interval (0..2^32)
+    // (i.e. closed interval [1..2^32-1], not including 0)
+    OVR_FORCE_INLINE uint32_t NextNonZero()
+    {
+        uint32_t n;
+        do
+        {
+            n = Next();
+        } while (n == 0);
+        return n;
+    }
+
+    // Double uniformly distributed over open interval (0..1)
+    OVR_FORCE_INLINE double Rand()
+    {
+        return NextNonZero() * (1.0 / 4294967296.0);    // 2^32
+    }
+
+    // Double uniformly distributed over open interval (dmin..dmax)
+    OVR_FORCE_INLINE double Rand(double dmin, double dmax)
+    {
+        return dmin + (dmax - dmin) * (1.0 / 4294967296.0) * NextNonZero(); // 2^32
+    }
+
+    // Integer uniformly distributed over closed interval [0..imax-1]
+    // (NOTE: Matalb randi(imax) returns 1..imax)
+    OVR_FORCE_INLINE int RandI(int imax)
+    {
+        return (int)(Next() % imax);
+    }
+
+    // Integer uniformly distributed over closed interval [imin..imax-1]
+    // (NOTE: Matlab randi() returns imin..imax)
+    OVR_FORCE_INLINE int RandI(int imin, int imax)
+    {
+        return imin + (int)(Next() % (imax - imin));
+    }
+
+    // Coordinate (x,y) uniformly distributed inside unit circle.
+    // Returns magnitude squared of (x,y)
+    OVR_FORCE_INLINE double RandInUnitCircle(double& x, double& y)
+    {
+        double r2;
+        do
+        {
+            x = Rand(-1.0, 1.0);
+            y = Rand(-1.0, 1.0);
+            r2 = x*x + y*y;
+        } while (r2 >= 1.0);
+        return r2;
+    }
+
+    // Standard normal (gaussian) distribution: mean 0.0, stdev 1.0
+    double RandN()
+    {
+        if (HaveRandN)
+        {
+            HaveRandN = false;
+            return NextRandN;
+        }
+        else
+        {
+            double x, y;
+            double r2 = RandInUnitCircle(x, y);
+            // Box-Muller transform
+            double f = sqrt(-2 * log(r2) / r2);
+
+            // Return first, save second for next call
+            NextRandN = y * f;
+            HaveRandN = true;
+
+            return x * f;
+        }
+    }
+
+    // Uniform coordinate (c,s) ON unit circle.
+    // This function computes cos(theta), sin(theta)
+    // of rotation uniform in (0..2*pi).
+    // [ c s] is a random 2D rotation matrix.
+    // [-s c]
+    // Reference: Numerical Recipes in C++, chap. 21
+    OVR_FORCE_INLINE void RandOnUnitCircle(double& c, double& s)
+    {
+        double r2 = RandInUnitCircle(c, s);
+        double normalize = 1.0 / sqrt(r2);
+        c *= normalize;
+        s *= normalize;
+    }
+
+    // Uniform coordinate (x,y,z,w) on surface of 4D hypersphere.
+    // This is a quaternion rotation uniformly distributed across all rotations
+    // Reference: Numerical Recipes in C++, chap. 21
+    OVR_FORCE_INLINE void RandOnUnitSphere4(double& x, double& y, double& z, double& w)
+    {
+        double r2xy = RandInUnitCircle(x, y);
+
+        double u, v;
+        double r2uv = RandInUnitCircle(u, v);
+
+        double f = sqrt((1.0 - r2xy) / r2uv);
+        z = u * f;
+        w = v * f;
+    }
+};
+
+} // namespace OVR
+
+#endif // OVR_Rand_h