C++ .inl file extension

samples/C++/Math.inl

@@ -0,0 +1,530 @@
+/*
+===========================================================================
+The Open Game Libraries.
+Copyright (C) 2007-2010 Lusito Software
+
+Author:  Santo Pfingsten (TTK-Bandit)
+Purpose: Math namespace
+-----------------------------------------
+
+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 __OG_MATH_INL__
+#define __OG_MATH_INL__
+
+namespace og {
+
+/*
+==============================================================================
+
+  Math
+
+==============================================================================
+*/
+
+/*
+================
+Math::Abs
+================
+*/
+OG_INLINE int Math::Abs( int i ) {
+#if 1
+	if ( i & 0x80000000 )
+		return 0x80000000 - (i & MASK_SIGNED);
+	return i;
+#else
+   int y = x >> 31;
+   return ( ( x ^ y ) - y );
+#endif
+}
+
+/*
+================
+Math::Fabs
+================
+*/
+OG_INLINE float Math::Fabs( float f ) {
+#if 1
+	uInt *pf = reinterpret_cast<uInt*>(&f);
+	*(pf) &= MASK_SIGNED;
+	return f;
+#else
+	return fabsf( f );
+#endif
+}
+
+/*
+================
+Math::Round
+================
+*/
+OG_INLINE float Math::Round( float f ) {
+	return floorf( f + 0.5f );
+}
+
+/*
+================
+Math::Floor
+================
+*/
+OG_INLINE float Math::Floor( float f ) {
+	return floorf( f );
+}
+
+/*
+================
+Math::Ceil
+================
+*/
+OG_INLINE float Math::Ceil( float f ) {
+	return ceilf( f );
+}
+
+/*
+================
+Math::Ftoi
+
+ok since this is SSE, why should the other ftoi be the faster one ?
+and: we might need to add a check for SSE extensions..
+because sse isn't *really* faster (I actually read that GCC does not handle
+SSE extensions perfectly. I'll find the link and send it to you when you're online)
+================
+*/
+OG_INLINE int Math::Ftoi( float f ) {
+	//! @todo	needs testing
+	// note: sse function cvttss2si
+#if OG_ASM_MSVC
+	int i;
+#if defined(OG_FTOI_USE_SSE)
+	if( SysInfo::cpu.general.SSE ) {
+		__asm cvttss2si	eax, f
+		__asm mov		i, eax
+		return i;
+	} else
+#endif
+	{
+		__asm fld		f
+		__asm fistp		i
+		//__asm mov eax, i // do we need this ? O_o
+	}
+	return i;
+#elif OG_ASM_GNU
+	int i;
+#if defined(OG_FTOI_USE_SSE)
+	if( SysInfo::cpu.general.SSE ) {
+		__asm__ __volatile__( "cvttss2si %1    \n\t"
+			: "=m" (i)
+			: "m" (f)
+		);
+	} else
+#endif
+	{
+		__asm__ __volatile__( "flds %1    \n\t"
+							  "fistpl %0  \n\t"
+			: "=m" (i)
+			: "m" (f)
+		);
+	}
+	return i;
+#else
+	// we use c++ cast instead of c cast (not sure why id did that)
+	return static_cast<int>(f);
+#endif
+}
+
+/*
+================
+Math::FtoiFast
+================
+*/
+OG_INLINE int Math::FtoiFast( float f ) {
+#if OG_ASM_MSVC
+	int i;
+	__asm fld		f
+	__asm fistp		i
+	//__asm mov eax, i // do we need this ? O_o
+	return i;
+#elif OG_ASM_GNU
+	int i;
+	__asm__ __volatile__( "flds %1    \n\t"
+						  "fistpl %0  \n\t"
+		: "=m" (i)
+		: "m" (f)
+	);
+	return i;
+#else
+	// we use c++ cast instead of c cast (not sure why id did that)
+	return static_cast<int>(f);
+#endif
+}
+
+/*
+================
+Math::Ftol
+================
+*/
+OG_INLINE long Math::Ftol( float f ) {
+#if OG_ASM_MSVC
+	long i;
+	__asm fld		f
+	__asm fistp		i
+	//__asm mov eax, i // do we need this ? O_o
+	return i;
+#elif OG_ASM_GNU
+	long i;
+	__asm__ __volatile__( "flds %1    \n\t"
+						  "fistpl %0  \n\t"
+		: "=m" (i)
+		: "m" (f)
+	);
+	return i;
+#else
+	// we use c++ cast instead of c cast (not sure why id did that)
+	return static_cast<long>(f);
+#endif
+}
+
+/*
+================
+Math::Sign
+================
+*/
+OG_INLINE float Math::Sign( float f )	{
+	if ( f > 0.0f )
+		return 1.0f;
+	if ( f < 0.0f )
+		return -1.0f;
+	return 0.0f;
+}
+
+/*
+================
+Math::Fmod
+================
+*/
+OG_INLINE float Math::Fmod( float numerator, float denominator ) {
+	return fmodf( numerator, denominator );
+}
+
+/*
+================
+Math::Modf
+================
+*/
+OG_INLINE float Math::Modf( float f, float& i ) {
+	return modff( f, &i );
+}
+OG_INLINE float Math::Modf( float f ) {
+	float i;
+	return modff( f, &i );
+}
+
+/*
+================
+Math::Sqrt
+================
+*/
+OG_INLINE float Math::Sqrt( float f ) {
+	return sqrtf( f );
+}
+
+/*
+================
+Math::InvSqrt
+
+Cannot be 0.0f
+================
+*/
+OG_INLINE float Math::InvSqrt( float f ) {
+	OG_ASSERT( f != 0.0f );
+	return 1.0f / sqrtf( f );
+}
+
+/*
+================
+Math::RSqrt
+
+Can be 0.0f
+================
+*/
+OG_INLINE float Math::RSqrt( float f ) {
+	float g = 0.5f * f;
+	int i = *reinterpret_cast<int *>(&f);
+
+	// do a guess
+	i = 0x5f375a86 - ( i>>1 );
+	f = *reinterpret_cast<float *>(&i);
+
+	// Newtons calculation
+	f = f * ( 1.5f - g * f * f );
+	return f;
+}
+
+/*
+================
+Math::Log/Log2/Log10
+
+Log of 0 is bad.
+I've also heard you're not really
+supposed to do log of negatives, yet
+they work fine.
+================
+*/
+OG_INLINE float Math::Log( float f ) {
+	OG_ASSERT( f != 0.0f );
+	return logf( f );
+}
+OG_INLINE float Math::Log2( float f ) {
+	OG_ASSERT( f != 0.0f );
+	return INV_LN_2 * logf( f );
+}
+OG_INLINE float Math::Log10( float f ) {
+	OG_ASSERT( f != 0.0f );
+	return INV_LN_10 * logf( f );
+}
+
+/*
+================
+Math::Pow
+================
+*/
+OG_INLINE float Math::Pow( float base, float exp ) {
+	return powf( base, exp );
+}
+
+/*
+================
+Math::Exp
+================
+*/
+OG_INLINE float Math::Exp( float f ) {
+	return expf( f );
+}
+
+/*
+================
+Math::IsPowerOfTwo
+================
+*/
+OG_INLINE bool Math::IsPowerOfTwo( int x ) {
+	// This is the faster of the two known methods
+	// with the x > 0 check moved to the beginning
+	return x > 0 && ( x & ( x - 1 ) ) == 0;
+}
+
+/*
+================
+Math::HigherPowerOfTwo
+================
+*/
+OG_INLINE int Math::HigherPowerOfTwo( int x ) {
+	x--;
+	x |= x >> 1;
+	x |= x >> 2;
+	x |= x >> 4;
+	x |= x >> 8;
+	x |= x >> 16;
+	return x + 1;
+}
+
+/*
+================
+Math::LowerPowerOfTwo
+================
+*/
+OG_INLINE int Math::LowerPowerOfTwo( int x ) {
+	return HigherPowerOfTwo( x ) >> 1;
+}
+
+/*
+================
+Math::FloorPowerOfTwo
+================
+*/
+OG_INLINE int Math::FloorPowerOfTwo( int x ) {
+	return IsPowerOfTwo( x ) ? x : LowerPowerOfTwo( x );
+}
+
+/*
+================
+Math::CeilPowerOfTwo
+================
+*/
+OG_INLINE int Math::CeilPowerOfTwo( int x ) {
+	return IsPowerOfTwo( x ) ? x : HigherPowerOfTwo( x );
+}
+
+/*
+================
+Math::ClosestPowerOfTwo
+================
+*/
+OG_INLINE int Math::ClosestPowerOfTwo( int x ) {
+	if ( IsPowerOfTwo( x ) )
+		return x;
+	int high = HigherPowerOfTwo( x );
+	int low = high >> 1;
+	return ((high-x) < (x-low)) ? high : low;
+}
+
+/*
+================
+Math::Digits
+================
+*/
+OG_INLINE int Math::Digits( int x ) {
+	int digits = 1;
+	int step = 10;
+	while (step <= x) {
+		digits++;
+		step *= 10;
+	}
+	return digits;
+}
+
+/*
+================
+Math::Sin/ASin
+================
+*/
+OG_INLINE float Math::Sin( float f ) {
+	return sinf( f );
+}
+OG_INLINE float Math::ASin( float f ) {
+	if ( f <= -1.0f )
+		return -HALF_PI;
+	if ( f >= 1.0f )
+		return HALF_PI;
+	return asinf( f );
+}
+
+/*
+================
+Math::Cos/ACos
+================
+*/
+OG_INLINE float Math::Cos( float f ) {
+	return cosf( f );
+}
+OG_INLINE float Math::ACos( float f ) {
+	if ( f <= -1.0f )
+		return PI;
+	if ( f >= 1.0f )
+		return 0.0f;
+	return acosf( f );
+}
+
+/*
+================
+Math::Tan/ATan
+================
+*/
+OG_INLINE float Math::Tan( float f ) {
+	return tanf( f );
+}
+OG_INLINE float Math::ATan( float f ) {
+	return atanf( f );
+}
+OG_INLINE float Math::ATan( float f1, float f2 ) {
+	return atan2f( f1, f2 );
+}
+
+/*
+================
+Math::SinCos
+================
+*/
+OG_INLINE void Math::SinCos( float f, float &s, float &c ) {
+#if OG_ASM_MSVC
+	// sometimes assembler is just waaayy faster
+	_asm {
+		fld		f
+		fsincos
+		mov		ecx, c
+		mov		edx, s
+		fstp	dword ptr [ecx]
+		fstp	dword ptr [edx]
+	}
+#elif OG_ASM_GNU
+	asm ("fsincos" : "=t" (c), "=u" (s) : "0" (f));
+#else
+	s = Sin(f);
+	c = Sqrt( 1.0f - s * s ); // faster than calling Cos(f)
+#endif
+}
+
+/*
+================
+Math::Deg2Rad
+================
+*/
+OG_INLINE float Math::Deg2Rad( float f ) {
+	return f * DEG_TO_RAD;
+}
+
+/*
+================
+Math::Rad2Deg
+================
+*/
+OG_INLINE float Math::Rad2Deg( float f ) {
+	return f * RAD_TO_DEG;
+}
+
+/*
+================
+Math::Square
+================
+*/
+OG_INLINE float Math::Square( float v ) {
+	return v * v;
+}
+
+/*
+================
+Math::Cube
+================
+*/
+OG_INLINE float Math::Cube( float v ) {
+	return v * v * v;
+}
+
+/*
+================
+Math::Sec2Ms
+================
+*/
+OG_INLINE int Math::Sec2Ms( int sec ) {
+	return sec * 1000;
+}
+
+/*
+================
+Math::Ms2Sec
+================
+*/
+OG_INLINE int Math::Ms2Sec( int ms ) {
+	return FtoiFast( ms * 0.001f );
+}
+
+}
+
+#endif