| 143 | |
| 144 | template <typename T> |
| 145 | T Vector2<T>::angle(const Vector2<T> &v2) const |
| 146 | { |
| 147 | const T len = this->length() * v2.length(); |
| 148 | if (len <= 0) { |
| 149 | return 0.0f; |
| 150 | } |
| 151 | const T cosv = ((*this)*v2) / len; |
| 152 | if (cosv >= 1) { |
| 153 | return 0.0f; |
| 154 | } |
| 155 | if (cosv <= -1) { |
| 156 | return M_PI; |
| 157 | } |
| 158 | return acosF(cosv); |
| 159 | } |
| 160 | |
| 161 | template <typename T> |
| 162 | T Vector2<T>::angle(void) const |