Tip of the Week #52 - Creating a Point On-Line Between Two 3D Points

By Matt McLean posted 08-17-2018 15:55


In many situations it is useful to create a point between two 3D points, with an interpolated elevation and a desired horizontal offset from one of the lines; here's how that can be done easily and efficiently!


I have two points separated by 141m horizontal, 10m vertical. In the plan view I have the point elevation displayed.


Short version:

Create Linestring between the two points. (direction matters)

On the Edit ribbon, use the break line command.

Create a point at End of line. (In Create Point drop-down)


Detailed version: 

First is to Create Linestring between the two points, starting from the point you want to set the offset distance.

I have drawn the line from point 1 to 2. After opening the Create Linestring command, you can press "Enter" to skip the first menu, and go directly to selecting the start and end points of your line. After clicking the two points, pressing "Esc" twice will exit the command.


Next, go to Edit > Lines > Break


Select the line (if it's not already), and enter the distance along the line you would like to create the new point. (This is why the direction the line was created matters) I would like my new point to be 50m from the start point.


Hit Break or press "Enter" on the keyboard.


Next, CAD > Points > Create Point (select the drop down) > End


Select the end of the broken line, and click Add or press "Enter". A point will be created here.


 If the linestrings are not desired, they can be deleted.


And there you have it! 


TBC - From Field to Finish With Confidence



09-12-2018 18:12

In other words, like Trimble Access calculating a point from a baseline.



09-10-2018 04:47

Thank you, Pete. What I'm saying is that we need a tool to create point by station and offset straight from two selected points not from a line. It is the drawing and erasing of lines I'm looking to circumvent.

09-09-2018 20:40

Hi Tobbe,

you talking about the following:







09-06-2018 02:37

Thanks, Matt. Creating a point from existing geometry must be the most used function in any survey software. The roundabout way in which TBC does it, with creating and then deleting a linestring seems redundant to me.


This workflow should be no longer than selecting two points, type in station and offset and hit enter.