1. Call the perpendicular lines creation mode of the Line command. The preview of resulting lines will appear. Their intersection point will follow the cursor.
2. Specify coordinates of the intersection point. While the preview of the line follows the cursor, absolute coordinates X and Y of the intersection point are indicated in the parameters window, as well as in the right side of the status bar. There is a checkbox to the left of each coordinate's input box in the parameters window. If you enable such checkbox, a value of a corresponding coordinate will be fixated and stop depending on the cursor position. Coordinates may be specified in one of the following ways:
•Place the cursor at an arbitrary point of drawing window without snapping to existing elements and then press or <Enter>.
•Type values via keyboard into the input boxes of the parameters window. The X coordinate box is active by default. Press <Tab> or click the desired box in order to switch between X and Y input. You may also input a variable name instead of a numerical value. Inputting a value enables a checkbox of a corresponding coordinate. In order to finish the input, press <Enter> or click anywhere within drawing window.
Upon specifying coordinates, a pair of perpendicular lines and a connected 2D node at their intersection will be created. Positions of the lines are defined by coordinate values, position of the node is defined by positions of the lines. Coordinate values are saved in line parameters (X for vertical line, Y for horizontal) and can be edited later.
After creating a pair of lines, the command stays in the perpendicular lines creation mode.