diff --git a/.vs/3dMath/v15/.suo b/.vs/3dMath/v15/.suo
index 7e1982f..e36491f 100644
Binary files a/.vs/3dMath/v15/.suo and b/.vs/3dMath/v15/.suo differ
diff --git a/GMath.cpp b/GMath.cpp
index dd8b1d9..ff5810d 100644
--- a/GMath.cpp
+++ b/GMath.cpp
@@ -1084,3 +1084,15 @@ GVector3 GLine::GetDir() const
 {
 	return v;
 }
+
+bool GLine::IsOnLine(const GPoint3 & q)
+{
+	return EQ_ZERO(dist(q, *this), PRECISION);
+}
+
+float dist(const GPoint3 & q, const GLine & l)
+{
+	GVector3 u = q - l.p;
+	GVector3 p = proj(u, l.v);
+	return norm(u - p);
+}
\ No newline at end of file
diff --git a/GMath.h b/GMath.h
index ff9532a..8d7efd2 100644
--- a/GMath.h
+++ b/GMath.h
@@ -222,4 +222,7 @@ public:
 
 	GVector3 GetPt() const;
 	GVector3 GetDir() const;
+
+	bool IsOnLine(const GPoint3& q);
+	friend float dist(const GPoint3& q, const GLine& l);
 };
\ No newline at end of file
diff --git a/main.cpp b/main.cpp
index d004704..cad1ad6 100644
--- a/main.cpp
+++ b/main.cpp
@@ -2,15 +2,15 @@
 
 int main() {
 
-	GLine l(GPoint3(0.0f, 0.0f, 0.0f), GVector3(1.0, 0.0f, 0.0f));
-	
-	GPoint3 p = l(2.0f);
+	GLine l(GPoint3(0.0f, 0.0f, 0.0f), GVector3(1.0f, 0.0f, 0.0f));
+	GPoint3 q(0.0f, 0.0f, 1.0f);
 
-	l.SetPt(GPoint3(0.0f, 0.0f, 1.0f));
-	l.SetDir(GVector3(1.0f, 0.0f, 0.0f));
+	float d = dist(q, l);
 
-	GPoint3 q = l(1.0f);
+	cout << d << endl;
 
-	cout << q << endl;
+	bool b = l.IsOnLine(GPoint3(0.0f, 0.0f, 0.0f));
+	bool b2 = l.IsOnLine(GPoint3(0.5f, 0.0f, 0.0f));
+	bool b3 = l.IsOnLine(GPoint3(0.5f, 0.5f, 0.0f));
 	return 0;
 }
\ No newline at end of file