Initial commit with PS4 and XBone stuff trimmed.

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diff --git a/src/Spectrum_Util.h b/src/Spectrum_Util.h
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+// This code contains NVIDIA Confidential Information and is disclosed 
+// under the Mutual Non-Disclosure Agreement. 
+// 
+// Notice 
+// ALL NVIDIA DESIGN SPECIFICATIONS AND CODE ("MATERIALS") ARE PROVIDED "AS IS" NVIDIA MAKES 
+// NO REPRESENTATIONS, WARRANTIES, EXPRESSED, IMPLIED, STATUTORY, OR OTHERWISE WITH RESPECT TO 
+// THE MATERIALS, AND EXPRESSLY DISCLAIMS ANY IMPLIED WARRANTIES OF NONINFRINGEMENT, 
+// MERCHANTABILITY, OR FITNESS FOR A PARTICULAR PURPOSE. 
+// 
+// NVIDIA Corporation assumes no responsibility for the consequences of use of such 
+// information or for any infringement of patents or other rights of third parties that may 
+// result from its use. No license is granted by implication or otherwise under any patent 
+// or patent rights of NVIDIA Corporation. No third party distribution is allowed unless 
+// expressly authorized by NVIDIA.  Details are subject to change without notice. 
+// This code supersedes and replaces all information previously supplied. 
+// NVIDIA Corporation products are not authorized for use as critical 
+// components in life support devices or systems without express written approval of 
+// NVIDIA Corporation. 
+// 
+// Copyright � 2008- 2013 NVIDIA Corporation. All rights reserved.
+//
+// NVIDIA Corporation and its licensors retain all intellectual property and proprietary
+// rights in and to this software and related documentation and any modifications thereto.
+// Any use, reproduction, disclosure or distribution of this software and related
+// documentation without an express license agreement from NVIDIA Corporation is
+// strictly prohibited.
+//
+
+#ifndef _NVWAVEWORKS_SPECTRUM_UTIL_H
+#define _NVWAVEWORKS_SPECTRUM_UTIL_H
+
+#ifndef GRAV_ACCEL
+#define GRAV_ACCEL	9.810f	// The acceleration of gravity, m/s^2
+#endif
+
+#ifndef PI
+#define PI 3.1415926536f
+#endif
+
+// Phillips Spectrum
+// K: normalized wave vector, W: wind direction, v: wind velocity, a: constant affecting factor
+FN_QUALIFIER float FN_NAME(Phillips)(float2 K, float2 W, float v, float a, float dir_depend, float small_wave_fraction)
+{
+	// largest possible wave from constant wind of velocity v
+	float l = v * v / GRAV_ACCEL;
+	// damp out waves with very small length w << l
+	float w = small_wave_fraction * l;
+
+	float Ksqr = K.x * K.x + K.y * K.y;
+	float Kcos = K.x * W.x + K.y * W.y;
+	float phillips = a * expf(-1 / (l * l * Ksqr)) / (Ksqr * Ksqr * Ksqr) * (Kcos * Kcos);
+
+	// filter out waves moving opposite to wind
+	if (Kcos < 0)
+		phillips *= (1.0f-dir_depend);
+
+	// damp out waves with very small length w << l
+	return phillips * expf(-Ksqr * w * w);
+}
+
+// Upper-bound estimate of integral of Phillips Spectrum power over disc-shaped 2D wave vector space of radius k centred on K = {0,0}
+// There is no wind velocity parameter, since the integral is rotationally invariant
+//
+FN_QUALIFIER float FN_NAME(UpperBoundPhillipsIntegral)(float k, float v, float a, float dir_depend, float /*small_wave_fraction*/)
+{
+	if(k <= 0.f) return 0.f;
+
+	// largest possible wave from constant wind of velocity v
+	float l = v * v / GRAV_ACCEL;
+
+	// integral has analytic form, yay!
+	float phillips_integ = 0.5f * PI * a * l * l * expf(-1.f/(k*k*l*l));
+
+	// dir_depend affects half the domain
+	phillips_integ *= (1.0f-0.5f*dir_depend);
+
+	// we may safely ignore 'small_wave_fraction' for an upper-bound estimate
+	return phillips_integ;
+}
+
+// Rectangular window, parameterised by in (i) and out (o) thresholds
+FN_QUALIFIER float FN_NAME(RectWindow)(float r, float i, float o)
+{
+	if(r < i)
+	{
+		return 0.f;
+	}
+	else if(r < o)
+	{
+		return 1.f;
+	}
+	else
+	{
+		return 0.f;
+	}
+}
+
+FN_QUALIFIER float FN_NAME(CalcH0)(	int nx, int ny,
+									float2 K,
+									float window_in, float window_out,
+									float2 wind_dir, float v, float dir_depend,
+									float a,
+									float norm,
+									float small_wave_fraction
+									)
+{
+	// distance from DC, in wave-numbers
+	float nr = sqrtf(float(nx*nx)+float(ny*ny));
+	float window = sqrtf(FN_NAME(RectWindow)(nr, window_in, window_out));
+
+	float amplitude = (K.x == 0 && K.y == 0) ? 0 : sqrtf(FN_NAME(Phillips)(K, wind_dir, v, a, dir_depend, small_wave_fraction));
+	amplitude *= norm;
+	amplitude *= window;
+	amplitude *= 0.7071068f;
+
+	return amplitude;
+}
+
+#endif //_NVWAVEWORKS_SPECTRUM_UTIL_H