# FixtureFromPointsToPoints3D

The FixtureFromPointsToPoints3D function Functions are tools that are available in Spreadsheet for processing and analyzing acquisitions or other results. You can add functions to your Spreadsheet job to create tool chains and produce results for specific applications. constructs a fixture A fixture is a coordinate location on the image that keeps the tool in the place determined by the fixture. that maps 3D points and shapes from space B to space A, using corresponding 3D points from the two spaces. The input points must be non-collinear.

The FixtureFromPointsToPoints3D function helps to generate a Fixture3D transform using N points from coordinate space A and the same points from coordinate space B. The number of points must be at least 3.

To convert points from 3D camera space to robot space, you have to set the coordinates of these N points in both the 3D camera space coordinate system and 3D robot space.

As an example, you can use the 4 top corners of the Frustum:

- To know the 3D coordinates of the 4 corners in robot space, use a tactile device.
- To know the 3D coordinates of the 4 corners in 3D camera space, use spreadsheet functions, like PointFromLines3D.

If you want the Fixture3D to convert points from camera space to robot space, set first the points in robot space, and then in camera space.

As an example, when you have a Fixture3D structure, you can use a Point3D function to get the picking point in robot space by using the picking point in 3D camera space and the previously computed Fixture3D.