diff --git a/gglm/geometric.go b/gglm/geometric.go
index 810db86..35f586e 100755
--- a/gglm/geometric.go
+++ b/gglm/geometric.go
@@ -73,3 +73,36 @@ func SqrDistVec4(v1, v2 *Vec4) float32 {
 	w := v1.Data[3] - v2.Data[3]
 	return x*x + y*y + z*z + w*w
 }
+
+//ReflectVec2 returns the reflected vector of the incoming vector 'v', and the surface normal 'n'.
+//
+//Note: n must be normalized or you will get wrong results
+func ReflectVec2(v, n *Vec2) *Vec2 {
+
+	//reflectedVec = v − 2*dot(v, norm)*norm
+	d := 2 * (v.Data[0]*n.Data[0] + v.Data[1]*n.Data[1])
+
+	return &Vec2{
+		Data: [2]float32{
+			v.Data[0] - d*n.Data[0],
+			v.Data[1] - d*n.Data[1],
+		},
+	}
+}
+
+//ReflectVec3 returns the reflected vector of the incoming vector 'v', and the surface normal 'n'.
+//
+//Note: n must be normalized or you will get wrong results
+func ReflectVec3(v, n *Vec3) *Vec3 {
+
+	//reflectedVec = v − 2*dot(v, norm)*norm
+	d := 2 * (v.Data[0]*n.Data[0] + v.Data[1]*n.Data[1] + v.Data[2]*n.Data[2])
+
+	return &Vec3{
+		Data: [3]float32{
+			v.Data[0] - d*n.Data[0],
+			v.Data[1] - d*n.Data[1],
+			v.Data[2] - d*n.Data[2],
+		},
+	}
+}
diff --git a/gglm/geometric_test.go b/gglm/geometric_test.go
new file mode 100755
index 0000000..43f9558
--- /dev/null
+++ b/gglm/geometric_test.go
@@ -0,0 +1,139 @@
+package gglm_test
+
+import (
+	"testing"
+
+	"github.com/bloeys/gglm/gglm"
+)
+
+func TestDotVec2(t *testing.T) {
+
+	v1 := gglm.Vec2{Data: [2]float32{1, 2}}
+	v2 := gglm.Vec2{Data: [2]float32{3, 4}}
+	ans := float32(11)
+
+	res := gglm.DotVec2(&v1, &v2)
+	if res != ans {
+		t.Errorf("Got: %v; Expected: %v", res, ans)
+	}
+}
+
+func TestDotVec3(t *testing.T) {
+
+	v1 := gglm.Vec3{Data: [3]float32{1, 2, 3}}
+	v2 := gglm.Vec3{Data: [3]float32{4, 5, 6}}
+	ans := float32(32)
+
+	res := gglm.DotVec3(&v1, &v2)
+	if res != ans {
+		t.Errorf("Got: %v; Expected: %v", res, ans)
+	}
+}
+
+func TestDotVec4(t *testing.T) {
+
+	v1 := gglm.Vec4{Data: [4]float32{1, 2, 3, 4}}
+	v2 := gglm.Vec4{Data: [4]float32{5, 6, 7, 8}}
+	ans := float32(70)
+
+	res := gglm.DotVec4(&v1, &v2)
+	if res != ans {
+		t.Errorf("Got: %v; Expected: %v", res, ans)
+	}
+}
+
+func TestDistVec2(t *testing.T) {
+
+	v1 := gglm.Vec2{Data: [2]float32{1, 2}}
+	v2 := gglm.Vec2{Data: [2]float32{3, 4}}
+	ans := float32(2.828427)
+
+	res := gglm.DistVec2(&v1, &v2)
+	if res != ans {
+		t.Errorf("Got: %v; Expected: %v", res, ans)
+	}
+}
+
+func TestDistVec3(t *testing.T) {
+
+	v1 := gglm.Vec3{Data: [3]float32{1, 2, 3}}
+	v2 := gglm.Vec3{Data: [3]float32{4, 5, 6}}
+	ans := float32(5.196152)
+
+	res := gglm.DistVec3(&v1, &v2)
+	if res != ans {
+		t.Errorf("Got: %v; Expected: %v", res, ans)
+	}
+}
+
+func TestDistVec4(t *testing.T) {
+
+	v1 := gglm.Vec4{Data: [4]float32{1, 2, 3, 4}}
+	v2 := gglm.Vec4{Data: [4]float32{5, 6, 7, 8}}
+	ans := float32(8)
+
+	res := gglm.DistVec4(&v1, &v2)
+	if res != ans {
+		t.Errorf("Got: %v; Expected: %v", res, ans)
+	}
+}
+
+func TestSqrDistVec2(t *testing.T) {
+
+	v1 := gglm.Vec2{Data: [2]float32{1, 2}}
+	v2 := gglm.Vec2{Data: [2]float32{3, 4}}
+	ans := float32(8)
+
+	res := gglm.SqrDistVec2(&v1, &v2)
+	if res != ans {
+		t.Errorf("Got: %v; Expected: %v", res, ans)
+	}
+}
+
+func TestSqrDistVec3(t *testing.T) {
+
+	v1 := gglm.Vec3{Data: [3]float32{1, 2, 3}}
+	v2 := gglm.Vec3{Data: [3]float32{4, 5, 6}}
+	ans := float32(27)
+
+	res := gglm.SqrDistVec3(&v1, &v2)
+	if res != ans {
+		t.Errorf("Got: %v; Expected: %v", res, ans)
+	}
+}
+
+func TestSqrDistVec4(t *testing.T) {
+
+	v1 := gglm.Vec4{Data: [4]float32{1, 2, 3, 4}}
+	v2 := gglm.Vec4{Data: [4]float32{5, 6, 7, 8}}
+	ans := float32(64)
+
+	res := gglm.SqrDistVec4(&v1, &v2)
+	if res != ans {
+		t.Errorf("Got: %v; Expected: %v", res, ans)
+	}
+}
+
+func TestReflectVec2(t *testing.T) {
+
+	v1 := gglm.Vec2{Data: [2]float32{1, 2}}
+	n := gglm.Vec2{Data: [2]float32{0, 1}}
+	ans := gglm.Vec2{Data: [2]float32{1, -2}}
+
+	res := gglm.ReflectVec2(&v1, &n)
+	if !res.Eq(&ans) {
+		t.Errorf("Got: %v; Expected: %v", res, ans)
+	}
+}
+
+func TestReflectVec3(t *testing.T) {
+
+	v1 := gglm.Vec3{Data: [3]float32{1, 2, 3}}
+	n := gglm.Vec3{Data: [3]float32{0, 1, 0}}
+	ans := gglm.Vec3{Data: [3]float32{1, -2, 3}}
+
+	res := gglm.ReflectVec3(&v1, &n)
+	if !res.Eq(&ans) {
+		t.Errorf("Got: %v; Expected: %v", res, ans)
+	}
+}
diff --git a/gglm/scalar.go b/gglm/scalar.go
new file mode 100755
index 0000000..69c3e02
--- /dev/null
+++ b/gglm/scalar.go
@@ -0,0 +1,16 @@
+package gglm
+
+import "math"
+
+//F32Epsilon = 0.0000005
+const F32Epsilon float32 = 1e-6
+
+//EqF32 true if abs(f1-f2) <= F32Epsilon
+func EqF32(f1, f2 float32) bool {
+	return math.Abs(float64(f1-f2)) <= float64(F32Epsilon)
+}
+
+//EqF32Epsilon true if abs(f1-f2) <= eps
+func EqF32Epsilon(f1, f2, eps float32) bool {
+	return math.Abs(float64(f1-f2)) <= float64(eps)
+}
diff --git a/main.go b/main.go
index 7afdf6f..275abe6 100755
--- a/main.go
+++ b/main.go
@@ -120,4 +120,10 @@ func main() {
 	vec3A := gglm.Vec3{Data: [3]float32{1, 2, 3}}
 	lol := gglm.MulMat3Vec3(&mat3A, &vec3A)
 	println(lol.String())
+
+	//ReflectVec2
+	vec2B := &gglm.Vec2{Data: [2]float32{4, 5}}
+	normA := &gglm.Vec2{Data: [2]float32{0, 1}}
+	rVec2A := gglm.ReflectVec2(vec2B, normA)
+	println(rVec2A.String())
 }
diff --git a/main_test.go b/main_test.go
index f13e073..2099bcb 100755
--- a/main_test.go
+++ b/main_test.go
@@ -7,8 +7,8 @@ import (
 )
 
 var (
-	dotVec2Result  float32 = 0
-	dotVec3Result  float32 = 0
+	dotVec2Result  float32
+	dotVec3Result  float32
 	crossResult    *gglm.Vec3
 	mulMat4Vec4Res *gglm.Vec4
 )