// ²Ù×÷·û vec4 operator+(vec4 left, const vec4& right) { return left.add(right); }
vec4 operator+(vec4 vector, const vec4& other_vector) { return vector.add(other_vector); }
// ²Ù×÷·û vec4 operator+(vec4 left, const vec4& right) { return left.add(right); }
vec4 operator+(vec4 vector, const vec4& other_vector) { return vector.add(other_vector); }