Getting Right to the Point
Drag a point parameter from the (parameters, geometry) tab onto the canvas. The parameter will be orange, because it is not yet attached to any information that would make it meaningful.
To change this, right-click the point parameter and click “set one point.” Now you are in Rhino’s interface, and the cursor in the command bar should be blinking. Type in a coordinate to reference. We used the origin, or 0,0,0. Hit the space bar or press enter to return to Grasshopper. Now the point component should be gray, and in the Rhino window, you will see a red x marking your point parameter. When you click on the component, it will turn green, as will the x in the Rhino window.
To reset the point to a different location, right-click on the component, and repeat the “set one point” process. You should see the x move around your Rhino screen as you reset the point. (Use a top view with a grid for the most visible results.)