263 lines
		
	
	
		
			6.5 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			263 lines
		
	
	
		
			6.5 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
///////////////////////////////////////////////////////////////////////////////////////////////////
 | 
						|
// OpenGL Mathematics Copyright (c) 2005 - 2014 G-Truc Creation (www.g-truc.net)
 | 
						|
///////////////////////////////////////////////////////////////////////////////////////////////////
 | 
						|
// Created : 2005-12-21
 | 
						|
// Updated : 2008-11-27
 | 
						|
// Licence : This source is under MIT License
 | 
						|
// File    : glm/gtx/quaternion.inl
 | 
						|
///////////////////////////////////////////////////////////////////////////////////////////////////
 | 
						|
 | 
						|
#include <limits>
 | 
						|
#include "../gtc/constants.hpp"
 | 
						|
 | 
						|
namespace glm
 | 
						|
{
 | 
						|
	template <typename T, precision P>
 | 
						|
	GLM_FUNC_QUALIFIER detail::tvec3<T, P> cross
 | 
						|
	(
 | 
						|
		detail::tvec3<T, P> const & v,
 | 
						|
		detail::tquat<T, P> const & q
 | 
						|
	)
 | 
						|
	{
 | 
						|
		return inverse(q) * v;
 | 
						|
	}
 | 
						|
 | 
						|
	template <typename T, precision P>
 | 
						|
	GLM_FUNC_QUALIFIER detail::tvec3<T, P> cross
 | 
						|
	(
 | 
						|
		detail::tquat<T, P> const & q,
 | 
						|
		detail::tvec3<T, P> const & v
 | 
						|
	)
 | 
						|
	{
 | 
						|
		return q * v;
 | 
						|
	}
 | 
						|
 | 
						|
	template <typename T, precision P>
 | 
						|
	GLM_FUNC_QUALIFIER detail::tquat<T, P> squad
 | 
						|
	(
 | 
						|
		detail::tquat<T, P> const & q1,
 | 
						|
		detail::tquat<T, P> const & q2,
 | 
						|
		detail::tquat<T, P> const & s1,
 | 
						|
		detail::tquat<T, P> const & s2,
 | 
						|
		T const & h)
 | 
						|
	{
 | 
						|
		return mix(mix(q1, q2, h), mix(s1, s2, h), static_cast<T>(2) * (static_cast<T>(1) - h) * h);
 | 
						|
	}
 | 
						|
 | 
						|
	template <typename T, precision P>
 | 
						|
	GLM_FUNC_QUALIFIER detail::tquat<T, P> intermediate
 | 
						|
	(
 | 
						|
		detail::tquat<T, P> const & prev,
 | 
						|
		detail::tquat<T, P> const & curr,
 | 
						|
		detail::tquat<T, P> const & next
 | 
						|
	)
 | 
						|
	{
 | 
						|
		detail::tquat<T, P> invQuat = inverse(curr);
 | 
						|
		return exp((log(next + invQuat) + log(prev + invQuat)) / static_cast<T>(-4)) * curr;
 | 
						|
	}
 | 
						|
 | 
						|
	template <typename T, precision P>
 | 
						|
	GLM_FUNC_QUALIFIER detail::tquat<T, P> exp
 | 
						|
	(
 | 
						|
		detail::tquat<T, P> const & q
 | 
						|
	)
 | 
						|
	{
 | 
						|
		detail::tvec3<T, P> u(q.x, q.y, q.z);
 | 
						|
		T Angle = glm::length(u);
 | 
						|
		if (Angle < epsilon<T>())
 | 
						|
			return detail::tquat<T, P>();
 | 
						|
 | 
						|
		detail::tvec3<T, P> v(u / Angle);
 | 
						|
		return detail::tquat<T, P>(cos(Angle), sin(Angle) * v);
 | 
						|
	}
 | 
						|
 | 
						|
	template <typename T, precision P>
 | 
						|
	GLM_FUNC_QUALIFIER detail::tquat<T, P> log
 | 
						|
	(
 | 
						|
		detail::tquat<T, P> const & q
 | 
						|
	)
 | 
						|
	{
 | 
						|
		detail::tvec3<T, P> u(q.x, q.y, q.z);
 | 
						|
		T Vec3Len = length(u);
 | 
						|
 | 
						|
		if (Vec3Len < epsilon<T>())
 | 
						|
		{
 | 
						|
			if(q.w > static_cast<T>(0))
 | 
						|
				return detail::tquat<T, P>(log(q.w), static_cast<T>(0), static_cast<T>(0), static_cast<T>(0));
 | 
						|
			else if(q.w < static_cast<T>(0))
 | 
						|
				return detail::tquat<T, P>(log(-q.w), pi<T>(), static_cast<T>(0), static_cast<T>(0));
 | 
						|
			else
 | 
						|
				return detail::tquat<T, P>(std::numeric_limits<T>::infinity(), std::numeric_limits<T>::infinity(), std::numeric_limits<T>::infinity(), std::numeric_limits<T>::infinity());
 | 
						|
		}
 | 
						|
		else
 | 
						|
		{
 | 
						|
			T QuatLen = sqrt(Vec3Len * Vec3Len + q.w * q.w);
 | 
						|
			T t = atan(Vec3Len, T(q.w)) / Vec3Len;
 | 
						|
			return detail::tquat<T, P>(log(QuatLen), t * q.x, t * q.y, t * q.z);
 | 
						|
		}
 | 
						|
	}
 | 
						|
 | 
						|
	template <typename T, precision P>
 | 
						|
	GLM_FUNC_QUALIFIER detail::tquat<T, P> pow
 | 
						|
	(
 | 
						|
		detail::tquat<T, P> const & x,
 | 
						|
		T const & y
 | 
						|
	)
 | 
						|
	{
 | 
						|
		if(abs(x.w) > (static_cast<T>(1) - epsilon<T>()))
 | 
						|
			return x;
 | 
						|
		T Angle = acos(y);
 | 
						|
		T NewAngle = Angle * y;
 | 
						|
		T Div = sin(NewAngle) / sin(Angle);
 | 
						|
		return detail::tquat<T, P>(
 | 
						|
			cos(NewAngle),
 | 
						|
			x.x * Div,
 | 
						|
			x.y * Div,
 | 
						|
			x.z * Div);
 | 
						|
	}
 | 
						|
 | 
						|
	//template <typename T, precision P>
 | 
						|
	//GLM_FUNC_QUALIFIER detail::tquat<T, P> sqrt
 | 
						|
	//(
 | 
						|
	//	detail::tquat<T, P> const & q
 | 
						|
	//)
 | 
						|
	//{
 | 
						|
	//	T q0 = static_cast<T>(1) - dot(q, q);
 | 
						|
	//	return T(2) * (T(1) + q0) * q;
 | 
						|
	//}
 | 
						|
 | 
						|
	template <typename T, precision P>
 | 
						|
	GLM_FUNC_QUALIFIER detail::tvec3<T, P> rotate
 | 
						|
	(
 | 
						|
		detail::tquat<T, P> const & q,
 | 
						|
		detail::tvec3<T, P> const & v
 | 
						|
	)
 | 
						|
	{
 | 
						|
		return q * v;
 | 
						|
	}
 | 
						|
 | 
						|
	template <typename T, precision P>
 | 
						|
	GLM_FUNC_QUALIFIER detail::tvec4<T, P> rotate
 | 
						|
	(
 | 
						|
		detail::tquat<T, P> const & q,
 | 
						|
		detail::tvec4<T, P> const & v
 | 
						|
	)
 | 
						|
	{
 | 
						|
		return q * v;
 | 
						|
	}
 | 
						|
 | 
						|
	template <typename T, precision P>
 | 
						|
	GLM_FUNC_QUALIFIER T extractRealComponent
 | 
						|
	(
 | 
						|
		detail::tquat<T, P> const & q
 | 
						|
	)
 | 
						|
	{
 | 
						|
		T w = static_cast<T>(1) - q.x * q.x - q.y * q.y - q.z * q.z;
 | 
						|
		if(w < T(0))
 | 
						|
			return T(0);
 | 
						|
		else
 | 
						|
			return -sqrt(w);
 | 
						|
	}
 | 
						|
 | 
						|
	template <typename T, precision P>
 | 
						|
	GLM_FUNC_QUALIFIER T length2
 | 
						|
	(
 | 
						|
		detail::tquat<T, P> const & q
 | 
						|
	)
 | 
						|
	{
 | 
						|
		return q.x * q.x + q.y * q.y + q.z * q.z + q.w * q.w;
 | 
						|
	}
 | 
						|
 | 
						|
	template <typename T, precision P>
 | 
						|
	GLM_FUNC_QUALIFIER detail::tquat<T, P> shortMix
 | 
						|
	(
 | 
						|
		detail::tquat<T, P> const & x,
 | 
						|
		detail::tquat<T, P> const & y,
 | 
						|
		T const & a
 | 
						|
	)
 | 
						|
	{
 | 
						|
		if(a <= static_cast<T>(0)) return x;
 | 
						|
		if(a >= static_cast<T>(1)) return y;
 | 
						|
 | 
						|
		T fCos = dot(x, y);
 | 
						|
		detail::tquat<T, P> y2(y); //BUG!!! tquat<T> y2;
 | 
						|
		if(fCos < static_cast<T>(0))
 | 
						|
		{
 | 
						|
			y2 = -y;
 | 
						|
			fCos = -fCos;
 | 
						|
		}
 | 
						|
 | 
						|
		//if(fCos > 1.0f) // problem
 | 
						|
		T k0, k1;
 | 
						|
		if(fCos > (static_cast<T>(1) - epsilon<T>()))
 | 
						|
		{
 | 
						|
			k0 = static_cast<T>(1) - a;
 | 
						|
			k1 = static_cast<T>(0) + a; //BUG!!! 1.0f + a;
 | 
						|
		}
 | 
						|
		else
 | 
						|
		{
 | 
						|
			T fSin = sqrt(T(1) - fCos * fCos);
 | 
						|
			T fAngle = atan(fSin, fCos);
 | 
						|
			T fOneOverSin = static_cast<T>(1) / fSin;
 | 
						|
			k0 = sin((static_cast<T>(1) - a) * fAngle) * fOneOverSin;
 | 
						|
			k1 = sin((static_cast<T>(0) + a) * fAngle) * fOneOverSin;
 | 
						|
		}
 | 
						|
 | 
						|
		return detail::tquat<T, P>(
 | 
						|
			k0 * x.w + k1 * y2.w,
 | 
						|
			k0 * x.x + k1 * y2.x,
 | 
						|
			k0 * x.y + k1 * y2.y,
 | 
						|
			k0 * x.z + k1 * y2.z);
 | 
						|
	}
 | 
						|
 | 
						|
	template <typename T, precision P>
 | 
						|
	GLM_FUNC_QUALIFIER detail::tquat<T, P> fastMix
 | 
						|
	(
 | 
						|
		detail::tquat<T, P> const & x,
 | 
						|
		detail::tquat<T, P> const & y,
 | 
						|
		T const & a
 | 
						|
	)
 | 
						|
	{
 | 
						|
		return glm::normalize(x * (static_cast<T>(1) - a) + (y * a));
 | 
						|
	}
 | 
						|
 | 
						|
	template <typename T, precision P>
 | 
						|
	GLM_FUNC_QUALIFIER detail::tquat<T, P> rotation
 | 
						|
	(
 | 
						|
		detail::tvec3<T, P> const & orig,
 | 
						|
		detail::tvec3<T, P> const & dest
 | 
						|
	)
 | 
						|
	{
 | 
						|
		T cosTheta = dot(orig, dest);
 | 
						|
		detail::tvec3<T, P> rotationAxis;
 | 
						|
 | 
						|
		if(cosTheta < static_cast<T>(-1) + epsilon<T>())
 | 
						|
		{
 | 
						|
			// special case when vectors in opposite directions :
 | 
						|
			// there is no "ideal" rotation axis
 | 
						|
			// So guess one; any will do as long as it's perpendicular to start
 | 
						|
			// This implementation favors a rotation around the Up axis (Y),
 | 
						|
			// since it's often what you want to do.
 | 
						|
			rotationAxis = cross(detail::tvec3<T, P>(0, 0, 1), orig);
 | 
						|
			if(length2(rotationAxis) < epsilon<T>()) // bad luck, they were parallel, try again!
 | 
						|
				rotationAxis = cross(detail::tvec3<T, P>(1, 0, 0), orig);
 | 
						|
 | 
						|
			rotationAxis = normalize(rotationAxis);
 | 
						|
			return angleAxis(pi<T>(), rotationAxis);
 | 
						|
		}
 | 
						|
 | 
						|
		// Implementation from Stan Melax's Game Programming Gems 1 article
 | 
						|
		rotationAxis = cross(orig, dest);
 | 
						|
 | 
						|
		T s = sqrt((T(1) + cosTheta) * static_cast<T>(2));
 | 
						|
		T invs = static_cast<T>(1) / s;
 | 
						|
 | 
						|
		return detail::tquat<T, P>(
 | 
						|
			s * static_cast<T>(0.5f), 
 | 
						|
			rotationAxis.x * invs,
 | 
						|
			rotationAxis.y * invs,
 | 
						|
			rotationAxis.z * invs);
 | 
						|
	}
 | 
						|
 | 
						|
}//namespace glm
 |