Added new scalar-product so it can be used s*v and v*s. Also slight extra...

Added new scalar-product so it can be used s*v and v*s. Also slight extra constraint in normalization

RayTracer/tools/Vec3.cpp

@@ -93,6 +93,9 @@ bool Vec3::operator!=(const Vec3& rhs) const {
 Vec3 Vec3::normalize() const {
 	Vec3 x(*this);
 	float l = x.length();
+	if (l == 0) {
+		return x;
+	}
 	return Vec3(x[0] / l, x[1] / l, x[2] / l);
 }
 float Vec3::length() const {
@@ -123,4 +126,8 @@ std::ostream& operator<<(std::ostream& os, const util::Vec3& rhs) {
 	os << "(" << rhs[0] << " ," << rhs[1] << " ," << rhs[2] << ")";
 	return os;
 }
+
+Vec3 operator*(float s, const Vec3& rhs) {
+	return rhs * s;
+}
 }  // namespace util
\ No newline at end of file

RayTracer/tools/Vec3.h

@@ -20,6 +20,7 @@ class Vec3 {
 	Vec3 operator+(const Vec3& rhs) const;
 	Vec3 operator*(const Vec3& rhs) const;
 	Vec3 operator*(float s) const;
+	friend Vec3 operator*(float s, const Vec3& rhs);
 	Vec3 operator/(const Vec3& rhs) const;
 	Vec3 operator/(const float div) const;
 	void operator-=(const Vec3& rhs);