ericw-tools/include/common/qvec.hh

170 lines
4.1 KiB
C++

/* Copyright (C) 2017 Eric Wasylishen
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
See file, 'COPYING', for details.
*/
#ifndef __COMMON_QVEC_HH__
#define __COMMON_QVEC_HH__
#ifndef qmax // FIXME: Remove this ifdef
#define qmax(a,b) (((a)>(b)) ? (a) : (b))
#define qmin(a,b) (((a)>(b)) ? (b) : (a))
#endif
template <int N, class T>
class qvec {
protected:
T v[N];
public:
qvec() {
for (int i=0; i<N; i++)
v[i] = 0;
}
qvec(const T &a) {
for (int i=0; i<N; i++)
v[i] = a;
}
qvec(const T &a, const T &b) {
v[0] = a;
if (1 < N)
v[1] = b;
for (int i=2; i<N; i++)
v[i] = 0;
}
qvec(const T &a, const T &b, const T &c) {
v[0] = a;
if (1 < N)
v[1] = b;
if (2 < N)
v[2] = c;
for (int i=3; i<N; i++)
v[i] = 0;
}
qvec(const T &a, const T &b, const T &c, const T &d) {
v[0] = a;
if (1 < N)
v[1] = b;
if (2 < N)
v[2] = c;
if (3 < N)
v[3] = d;
for (int i=4; i<N; i++)
v[i] = 0;
}
template <int N2>
qvec(const qvec<N2, T> &other) {
const int minSize = qmin(N,N2);
// truncates if `other` is longer than `this`
for (int i=0; i<minSize; i++)
v[i] = other[i];
// zero-fill if `other` is smaller than `this`
for (int i=minSize; i<N; i++)
v[i] = 0;
}
bool operator==(const qvec<N,T> &other) const {
for (int i=0; i<N; i++)
if (v[i] != other.v[i])
return false;
return true;
}
T operator[](const size_t idx) const {
return v[idx];
}
T &operator[](const size_t idx) {
return v[idx];
}
void operator+=(const qvec<N,T> &other) {
for (int i=0; i<N; i++)
v[i] += other.v[i];
}
void operator-=(const qvec<N,T> &other) {
for (int i=0; i<N; i++)
v[i] -= other.v[i];
}
void operator*=(const T &scale) {
for (int i=0; i<N; i++)
v[i] *= scale;
}
void operator/=(const T &scale) {
for (int i=0; i<N; i++)
v[i] /= scale;
}
qvec<N,T> operator+(const qvec<N,T> &other) const {
qvec<N,T> res(*this);
res += other;
return res;
}
qvec<N,T> operator-(const qvec<N,T> &other) const {
qvec<N,T> res(*this);
res -= other;
return res;
}
qvec<N,T> operator*(const T &scale) const {
qvec<N,T> res(*this);
res *= scale;
return res;
}
qvec<N,T> operator/(const T &scale) const {
qvec<N,T> res(*this);
res /= scale;
return res;
}
};
template <class T>
qvec<3,T> cross(const qvec<3,T> &v1, const qvec<3,T> &v2) {
return qvec<3,T>(v1[1] * v2[2] - v1[2] * v2[1],
v1[2] * v2[0] - v1[0] * v2[2],
v1[0] * v2[1] - v1[1] * v2[0]);
}
template <int N, class T>
qvec<N,T> dot(const qvec<N,T> &v1, const qvec<N,T> &v2) {
T result = 0;
for (int i=0; i<N; i++) {
result += v1[i] * v2[i];
}
return result;
}
using qvec2f = qvec<2, float>;
using qvec3f = qvec<3, float>;
using qvec4f = qvec<4, float>;
using qvec2d = qvec<2, double>;
using qvec3d = qvec<3, double>;
using qvec4d = qvec<4, double>;
#endif /* __COMMON_QVEC_HH__ */