diff --git a/tests/dimension.scad b/tests/dimension.scad
new file mode 100644
index 0000000..0c51ca4
--- /dev/null
+++ b/tests/dimension.scad
@@ -0,0 +1,81 @@
+//
+// NopSCADlib Copyright Chris Palmer 2018
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+include <../utils/core/core.scad>
+use <../utils/dimension.scad>
+
+
+module dimensions_3d_xy() {
+    dimension([0,0,0], [10,10,0], "", 0.2);
+    dimension([0,0,0], [10,-10,0], "", 0.2);
+    dimension([0,0,0], [-10,10,0], "", 0.2);
+    dimension([0,0,0], [-10,-10,0], "", 0.2);
+
+
+    dimension([0,0,0], [0,10,0], "", 0.2);
+    dimension([0,0,0], [0,-10,0], "", 0.2);
+    dimension([0,0,0], [10,0,0], "", 0.2);
+    dimension([0,0,0], [-10,0,0], "", 0.2);
+}
+
+module dimensions_3d_xyz() {
+    dimension([0,0,0], [10,10,10], "", 0.2);
+    dimension([0,0,0], [10,-10,10], "", 0.2);
+    dimension([0,0,0], [-10,10,10], "", 0.2);
+    dimension([0,0,0], [-10,-10,10], "", 0.2);
+
+    dimension([0,0,0], [10,10,-10], "", 0.2);
+    dimension([0,0,0], [10,-10,-10], "", 0.2);
+    dimension([0,0,0], [-10,10,-10], "", 0.2);
+    dimension([0,0,0], [-10,-10,-10], "", 0.2);
+
+    dimension([0,0,0], [-3,0,10], "", 0.2);
+    dimension([0,0,0], [0,0,-10], "", 0.2);
+    
+    dimension([0,0,0], [0,2,10], "", 0.2);
+    dimension([0,0,0], [0,2,-10], "", 0.2);
+    
+}
+
+module dimension_1d_x() {
+    dimension_x([12,0,0], [18,0,0]);
+    dimension_x([12,5,0], [18,10,0]);
+    dimension_x([12,5,0], [18,10,5]);   
+}
+
+module dimension_1d_y() {
+    dimension_y([12,0,0], [12,-5,0]);
+    dimension_y([12,-8,0], [18,-10,0]);
+    dimension_y([12,-5,0], [18,-10,5]);   
+}
+
+module dimension_1d_z() {
+    dimension_z([20,0,0], [20,0,5]);
+    dimension_z([20,0,0], [20,0,10]);
+    dimension_z([20,0,0], [20,10,10]);   
+}
+
+if($preview)
+    dimensions_3d_xy();
+    dimensions_3d_xyz();
+    dimension_1d_x();
+    dimension_1d_y();
+    dimension_1d_z();
+
+
+    
\ No newline at end of file
diff --git a/utils/dimension.scad b/utils/dimension.scad
new file mode 100644
index 0000000..81ff73e
--- /dev/null
+++ b/utils/dimension.scad
@@ -0,0 +1,157 @@
+//
+// NopSCADlib Copyright Chris Palmer 2018
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+
+//
+//! Annotation used in this documentation
+//
+
+include <../utils/core/core.scad>
+include <../utils/maths.scad>
+
+
+
+//if text is empty, will display the number value
+//text_plane is either "XY" or "XZ"
+module dimension(startpoint, endpoint, text = "", thickness = 0.1) {    
+    // Compute vector between points
+    direction = endpoint - startpoint;
+    length = norm(direction);
+    midpoint = (startpoint + endpoint) / 2;
+
+    // Ensure nonzero values for calculations
+    dir_xy = norm([direction.x, direction.y]);
+
+    // Compute rotation angles safely
+    //azimuth = (dir_xy == 0) ? 0 : atan2(direction.y, direction.x); 
+    azimuth = atan2(direction.y, direction.x); 
+    /*elevation = (direction.x == 0 && direction.y == 0) 
+                ? ((direction.z > 0) ? -90 : 90) 
+                : -atan2(direction.z, dir_xy);*/
+    elevation = -atan2(direction.z, dir_xy);
+
+    // Draw measurement line as a thin cylinder
+    translate(midpoint)
+    rotate([0, elevation, azimuth])
+    rotate([0, 90, 0]) 
+    cylinder(d = thickness, h = length - thickness * 2, center = true);
+
+    // Draw endpoint markers
+    translate(startpoint) 
+    rotate([0, elevation - 90, azimuth]) 
+    translate([0, 0, -thickness * 4]) 
+    cylinder(h = thickness * 4, r1 = thickness * 2, r2 = 0);
+    
+    translate(endpoint) 
+    rotate([0, elevation + 90, azimuth]) 
+    translate([0, 0, -thickness * 4]) 
+    cylinder(h = thickness * 4, r1 = thickness * 2, r2 = 0);
+
+    // Draw the text/distance
+    dir = (length > 0) ? (direction / length) * thickness * 4 : [1, 0, 0]; 
+    up_dir = rotate_vector_3d([0,1,0], [0,0,1] ,azimuth);
+    
+    translate(midpoint + up_dir*0.66)
+    rotate([0, elevation, azimuth]) 
+    linear_extrude(thickness)
+    text(text == "" ? str(length) : text, size = thickness * 5, valign = "center", halign = "center");
+}
+
+//offset will detirmine how much space is between the measured point and the dimension
+//for x, this offset will be in the y direction
+module dimension_x(startpoint, endpoint, offset = 1, text = "", thickness = 0.1) {
+    y = max(startpoint.y, endpoint.y) + offset;
+    z = max(startpoint.z, endpoint.z) ;
+    dimension([startpoint.x, y, z], [endpoint.x, y, z], text, thickness);
+    
+    v1= [startpoint.x, y, z]-startpoint;
+    h1 = norm(v1);
+    axis1 = cross([0,0,1], v1);
+    angle1 = atan2(norm(axis1), v1.z);    
+    translate(startpoint)
+    rotate(angle1, axis1)
+        cylinder( h= h1+thickness*2, d=thickness);
+        
+        
+    v2= [endpoint.x, y, z]-endpoint;
+    h2 = norm(v2);
+    axis2 = cross([0,0,1], v2);
+    angle2 = atan2(norm(axis2), v2.z);
+    
+    translate(endpoint)
+    rotate(angle2, axis2)
+        cylinder( h= h2+thickness*2, d=thickness);          
+}
+
+//offset will detirmine how much space is between the measured point and the dimension
+//for y, this offset will be in the x direction
+module dimension_y(startpoint, endpoint, offset = 1, text = "", thickness = 0.1) {
+    x = max(startpoint.x, endpoint.x) + offset;
+    z = max(startpoint.z, endpoint.z) ;
+    dimension([x, startpoint.y, z], [x, endpoint.y, z], text, thickness);
+    
+    v1= [x, startpoint.y, z]-startpoint;
+    h1 = norm(v1);
+    axis1 = cross([0,0,1], v1);
+    angle1 = atan2(norm(axis1), v1.z);
+    
+    translate(startpoint)
+    rotate(angle1, axis1)
+        cylinder( h= h1+thickness*2, d=thickness);
+        
+        
+    v2= [x, endpoint.y, z]-endpoint;
+    h2 = norm(v2);
+    axis2 = cross([0,0,1], v2);
+    angle2 = atan2(norm(axis2), v2.z);
+    
+    translate(endpoint)
+    rotate(angle2, axis2)
+        cylinder( h= h2+thickness*2, d=thickness);          
+}
+
+//offset will detirmine how much space is between the measured point and the dimension
+//for z, this offset will be in the x direction
+module dimension_z(startpoint, endpoint, offset = 1, text = "", thickness = 0.1) {
+    x = max(startpoint.x, endpoint.x) + offset;
+    y = max(startpoint.y, endpoint.y) ;
+    dimension([x, y, startpoint.z], [x, y, endpoint.z], text, thickness);
+    
+    v1= [x, y, startpoint.z]-startpoint;
+    h1 = norm(v1);
+    axis1 = cross([0,0,1], v1);
+    angle1 = atan2(norm(axis1), v1.z);
+    
+    translate(startpoint)
+    rotate(angle1, axis1)
+        cylinder( h= h1+thickness*2, d=thickness);
+        
+        
+    v2= [x, y, endpoint.z]-endpoint;
+    h2 = norm(v2);
+    axis2 = cross([0,0,1], v2);
+    angle2 = atan2(norm(axis2), v2.z);
+    
+    translate(endpoint)
+    rotate(angle2, axis2)
+        cylinder( h= h2+thickness*2, d=thickness);          
+}
+
+
+
+
diff --git a/utils/maths.scad b/utils/maths.scad
index 3d03f47..4fea047 100644
--- a/utils/maths.scad
+++ b/utils/maths.scad
@@ -191,3 +191,32 @@ function cubic_real_roots(a, b, c, d) = //! Returns real roots of cubic equation
 function path_length(path, i = 0, length = 0) = //! Calculated the length along a path
     i >= len(path) - 1 ? length
                        : path_length(path, i + 1, length + norm(path[i + 1] - path[i]));
+
+                       function rotate_vector_2d(v, angle) = [
+    v[0] * cos(angle) - v[1] * sin(angle),
+    v[0] * sin(angle) + v[1] * cos(angle)
+];
+
+function rotate_vector_2d(v, angle) = [
+    v[0] * cos(angle) - v[1] * sin(angle),
+    v[0] * sin(angle) + v[1] * cos(angle)
+];
+
+function rotation_matrix(axis, angle) = let(
+    u = axis / norm(axis), // Normalize axis
+    ux = u[0], uy = u[1], uz = u[2],
+    cosA = cos(angle), sinA = sin(angle),
+    one_minus_cosA = 1 - cosA
+) [
+    [cosA + ux*ux*one_minus_cosA,    ux*uy*one_minus_cosA - uz*sinA,  ux*uz*one_minus_cosA + uy*sinA],
+    [uy*ux*one_minus_cosA + uz*sinA, cosA + uy*uy*one_minus_cosA,     uy*uz*one_minus_cosA - ux*sinA],
+    [uz*ux*one_minus_cosA - uy*sinA, uz*uy*one_minus_cosA + ux*sinA,  cosA + uz*uz*one_minus_cosA]
+];
+
+function rotate_vector_3d(v, axis, angle) = let(
+    mat = rotation_matrix(axis, angle)
+) [
+    mat[0][0]*v[0] + mat[0][1]*v[1] + mat[0][2]*v[2],
+    mat[1][0]*v[0] + mat[1][1]*v[1] + mat[1][2]*v[2],
+    mat[2][0]*v[0] + mat[2][1]*v[1] + mat[2][2]*v[2]
+];
\ No newline at end of file