Added initial Smoothed Particle Hydrodynamics implementation (SPH), for CPU and CUDA.

This software is contributed under the ZLib license by Rama Hoetzlein, http://www.rchoetzlein.com
We plan to integrate the SPH into the core Bullet library, including interaction with rigid bodies and soft bodies.

Extras/sph/common/common_defs.h

@@ -0,0 +1,52 @@
+/*
+  FLUIDS v.1 - SPH Fluid Simulator for CPU and GPU
+  Copyright (C) 2009. Rama Hoetzlein, http://www.rchoetzlein.com
+
+  ZLib license
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#ifndef COMMON_DEF
+	#define COMMON_DEF
+
+	// Global defs
+
+	//#define		USE_SHADOWS			// Disable if you don't have FBOs, or to greatly speed up demo.
+
+//	#define		USE_JPEG
+
+	#define		BUILD_CUDA			// CUDA - Visual Studio 2005 only (as of April 2009)
+
+	#define TEX_SIZE		2048	
+	#define LIGHT_NEAR		0.5
+	#define LIGHT_FAR		300.0
+	#define DEGtoRAD		(3.141592/180.0)
+
+	#ifdef _MSC_VER
+		#include <windows.h>
+	#else
+		typedef unsigned int		DWORD;
+	#endif
+	typedef unsigned int		uint;
+
+	#define COLOR(r,g,b)	( (DWORD(r*255.0f)<<24) | (DWORD(g*255.0f)<<16) | (DWORD(b*255.0f)<<8) )
+	#define COLORA(r,g,b,a)	( (DWORD(r*255.0f)<<24) | (DWORD(g*255.0f)<<16) | (DWORD(b*255.0f)<<8) | DWORD(a*255.0f) )
+	#define RED(c)			(float((c>>24) & 0xFF)/255.0)
+	#define GRN(c)			(float((c>>16) & 0xFF)/255.0)
+	#define BLUE(c)			(float((c>>8) & 0xFF)/255.0)
+	#define ALPH(c)			(float(c & 0xFF)/255.0)
+#endif