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#ifndef GFXVEC4_INCLUDED // -*- C++ -*-
#define GFXVEC4_INCLUDED
#if !defined(__GNUC__)
# pragma once
#endif
/************************************************************************
4D Vector class
$Id: vec4.h 427 2004-09-27 04:45:31Z garland $
************************************************************************/
#include "vec3.h"
namespace gfx
{
template<class T>
class TVec4 {
private:
T elt[4];
public:
// Standard constructors
//
TVec4(T s=0) { *this = s; }
TVec4(T x, T y, T z, T w) { elt[0]=x; elt[1]=y; elt[2]=z; elt[3]=w; }
// Copy constructors & assignment operators
template<class U> TVec4(const TVec4<U>& v) { *this = v; }
template<class U> TVec4(const TVec3<U>& v,T w)
{ elt[0]=v[0]; elt[1]=v[1]; elt[2]=v[2]; elt[3]=w; }
template<class U> TVec4(const U v[4])
{ elt[0]=v[0]; elt[1]=v[1]; elt[2]=v[2]; elt[3]=v[3]; }
template<class U> TVec4& operator=(const TVec4<U>& v)
{ elt[0]=v[0]; elt[1]=v[1]; elt[2]=v[2]; elt[3]=v[3]; return *this; }
TVec4& operator=(T s) { elt[0]=elt[1]=elt[2]=elt[3]=s; return *this; }
// Descriptive interface
//
typedef T value_type;
static int dim() { return 4; }
// Access methods
//
operator T*() { return elt; }
operator const T*() const { return elt; }
#ifndef HAVE_CASTING_LIMITS
T& operator[](int i) { return elt[i]; }
T operator[](int i) const { return elt[i]; }
operator const T*() { return elt; }
#endif
// Assignment and in-place arithmetic methods
//
inline TVec4& operator+=(const TVec4& v);
inline TVec4& operator-=(const TVec4& v);
inline TVec4& operator*=(T s);
inline TVec4& operator/=(T s);
};
////////////////////////////////////////////////////////////////////////
//
// Method definitions
//
template<class T> inline TVec4<T>& TVec4<T>::operator+=(const TVec4<T>& v)
{ elt[0]+=v[0]; elt[1]+=v[1]; elt[2]+=v[2]; elt[3]+=v[3]; return *this;}
template<class T> inline TVec4<T>& TVec4<T>::operator-=(const TVec4<T>& v)
{ elt[0]-=v[0]; elt[1]-=v[1]; elt[2]-=v[2]; elt[3]-=v[3]; return *this;}
template<class T> inline TVec4<T>& TVec4<T>::operator*=(T s)
{ elt[0] *= s; elt[1] *= s; elt[2] *= s; elt[3] *= s; return *this; }
template<class T> inline TVec4<T>& TVec4<T>::operator/=(T s)
{ elt[0] /= s; elt[1] /= s; elt[2] /= s; elt[3] /= s; return *this; }
////////////////////////////////////////////////////////////////////////
//
// Operator definitions
//
template<class T>
inline TVec4<T> operator+(const TVec4<T> &u, const TVec4<T> &v)
{ return TVec4<T>(u[0]+v[0], u[1]+v[1], u[2]+v[2], u[3]+v[3]); }
template<class T>
inline TVec4<T> operator-(const TVec4<T> &u, const TVec4<T>& v)
{ return TVec4<T>(u[0]-v[0], u[1]-v[1], u[2]-v[2], u[3]-v[3]); }
template<class T> inline TVec4<T> operator-(const TVec4<T> &u)
{ return TVec4<T>(-u[0], -u[1], -u[2], -u[3]); }
#if _MSC_VER>=1200
// Normally, we use the <class T, class N> construct below to allow the scalar
// argument to be different than the template type. This, for example, allows
// the user to write things like v/2. Unfortunately, Microsoft VC6.0 (aka
// v1200) gets confused by this. We used to include explicit versions for the
// case of int's, but this was causing silent (and incorrect) coercion of
// floats to ints.
//
template<class T> inline TVec4<T> operator*(T s, const TVec4<T> &v)
{ return TVec4<T>(v[0]*s, v[1]*s, v[2]*s, v[3]*s); }
template<class T> inline TVec4<T> operator*(const TVec4<T> &v, T s)
{ return s*v; }
template<class T> inline TVec4<T> operator/(const TVec4<T> &v, T s)
{ return TVec4<T>(v[0]/s, v[1]/s, v[2]/s, v[3]/s); }
#else
template<class T, class N> inline TVec4<T> operator*(N s, const TVec4<T> &v)
{ return TVec4<T>(v[0]*s, v[1]*s, v[2]*s, v[3]*s); }
template<class T, class N> inline TVec4<T> operator*(const TVec4<T> &v, N s)
{ return s*v; }
template<class T, class N> inline TVec4<T> operator/(const TVec4<T> &v, N s)
{ return TVec4<T>(v[0]/s, v[1]/s, v[2]/s, v[3]/s); }
#endif
template<class T> inline T operator*(const TVec4<T> &u, const TVec4<T> &v)
{ return u[0]*v[0] + u[1]*v[1] + u[2]*v[2] + u[3]*v[3]; }
template<class T>
inline std::ostream &operator<<(std::ostream &out, const TVec4<T>& v)
{ return out <<v[0] <<" " <<v[1] <<" " <<v[2] <<" " <<v[3]; }
template<class T>
inline std::istream &operator>>(std::istream &in, TVec4<T>& v)
{ return in >> v[0] >> v[1] >> v[2] >> v[3]; }
////////////////////////////////////////////////////////////////////////
//
// Misc. function definitions
//
template<class T>
inline TVec4<T> cross(const TVec4<T>& a, const TVec4<T>& b, const TVec4<T>& c)
{
// Code adapted from VecLib4d.c in Graphics Gems V
T d1 = (b[2] * c[3]) - (b[3] * c[2]);
T d2 = (b[1] * c[3]) - (b[3] * c[1]);
T d3 = (b[1] * c[2]) - (b[2] * c[1]);
T d4 = (b[0] * c[3]) - (b[3] * c[0]);
T d5 = (b[0] * c[2]) - (b[2] * c[0]);
T d6 = (b[0] * c[1]) - (b[1] * c[0]);
return TVec4<T>(- a[1] * d1 + a[2] * d2 - a[3] * d3,
a[0] * d1 - a[2] * d4 + a[3] * d5,
- a[0] * d2 + a[1] * d4 - a[3] * d6,
a[0] * d3 - a[1] * d5 + a[2] * d6);
}
template<class T> inline T norm2(const TVec4<T>& v) { return v*v; }
template<class T> inline T norm(const TVec4<T>& v) { return sqrt(norm2(v)); }
template<class T> inline void unitize(TVec4<T>& v)
{
T l = norm2(v);
if( l!=1.0 && l!=0.0 ) v /= sqrt(l);
}
template<class T> inline TVec3<T> proj(const TVec4<T>& v)
{
TVec3<T> u(v[0], v[1], v[2]);
if( v[3]!=1.0 && v[3]!=0.0 )
u /= v[3];
return u;
}
typedef TVec4<double> Vec4;
typedef TVec4<float> Vec4f;
} // namespace gfx
// GFXVEC4_INCLUDED
#endif