The Point, Line, Rectangle, Circle. and Angle tools use a crosshair to position the tool and perform measurements. The crosshair consists of four triangular sections pointing to an open center. All measurements are based at the center of the crosshair.

The crosshair can be in one of three visual states: Normal, Located and Find.

Normal: If the mouse is not positioned over the crosshair, it is in the normal state. The crosshair will appear red under the default color scheme.

Located: If the mouse is positioned over the crosshair, it is in the located state. The crosshair will appear yellow under the default color scheme. In addition to a color change, the crosshair will display a data window indicating the current position of the crosshair. A tooltip may also appear indicating which measurement point the crosshair represents.

Find: Sometimes it can be hard to find a tool on the screen. When a new tool is selected, it will flash its crosshairs between the normal and selected states for a few seconds to help you locate it. If you lose a tool after you have selected it, you can cause it to flash again by selecting Find Crosshair on the Tools menu or by using the shortcut Ctrl+F.

The current position of a crosshair can be read in two places. The first is in the tool information section of the Meazure program window. The second place is the data window associated with the crosshair. The data window is displayed when the mouse is placed over the crosshair. The Line and Rectangle tools have two crosshairs called Point 1 and Point 2 respectively. The Circle tool has two crosshairs called the Vertex at the center of the circle, and Point 1 on the circumference of the circle. The Angle tool has three crosshairs called Point 1, Point 2, and Vertex respectively. You can determine whether a crosshair is Point 1, 2 or the vertex either by looking at the data window or the tooltip associated with the crosshair.

Measurements are taken by moving a crosshair to the desired position on the screen. There are three ways to move a crosshair: mouse dragging, keyboard positioning, and fine positioning.

Mouse dragging: The fastest way to position a crosshair is by dragging it using the mouse. Position the mouse over the crosshair so that it is in the located state. Press the left mouse button and drag the crosshair to the desired position. The position of the crosshair will be continuously displayed and the magnifier window will display the area around the crosshair as it is being dragged.

Keyboard positioning: The crosshair can be positioned by entering a position in the text fields of tool information section of the program. After typing in the position, press Enter to move the crosshair to the new position.

Fine positioning: To move the crosshair in single pixel increments use the up/down buttons located next to each position text field.

The display of the crosshair can be toggled either by selecting the Hide Crosshairs item on the Tools menu or by pressing Ctrl+B.

The colors, opacity and other characteristics of the crosshair and data window can be changed using the Tools panel on the Preferences dialog.