## Switching Between Curve and Surface Modes

Operation | Graphics Display Window | Change Curve/Surface Mode |

The optional package “Curves and Surfaces” must have been purchased for your system in order to access these modes. You can use these modes with Program mode to take offline hits on your CAD model's wire frame or surface entities.

Curve Mode

The Curve mode option makes a wire frame's model of curves and lines selectable when clicking on the CAD data in the Graphics Display window. You must import a wire frame model for this option to become available. This mode works well for all Measured Features.

However, two graphic views are required to take hits in Curve mode. You can set up views using the View Setup dialog box. See "Setting Up the Screen View". The picture to the right illustrates this. If your working plane is the Z+ plane, the top half of the screen (A) would be in the Z+ view and would be used to take hits while the bottom half of the screen (B) would be used to set the probe's depth. | Sample Graphics Display Window Split to Show Two Different Wire frame Views of the Part

The following table discusses the mouse operations you can use to set your probe's depth and take hits to insert measured features into your part program. The table below assumes that Z+ is your working plane. You must also be in Program mode for these to work:

Curve Mode Mouse Operations | Split Screen to Use | Description
Right-click | Screen B in the above picture | This sets the approximate animated probe depth at the current mouse pointer position. Use this to create Move Points when programming in offline mode. See "Inserting a Move Point Command" in "Inserting Move Commands".
Right-click + drag | Screen B in the above picture | This sets the depth for your next inserted hits on the nearest wire frame entity when you release the mouse button. Use this to set the depth for measured lines, circles and cylinders.
Left-click | Screen A in the above picture | This selects the nearest line or circle and takes equally spaced hits at the current depth setting based on the settings in the General tab of the Setup Options dialog box. See "Edit Boxes for the General tab" in "Setting Your Preferences".
Left-click + drag | Screen A in the above picture | This takes a single hit at the current depth setting on a line, arc or circle. The hit direction depends on which side of the wire you release your mouse. Always approach from the side of the wire the machine would approach from.
Left-click + hold and release | Screen A in the above picture | This delayed click takes a hit at the pointer's position at the current depth setting. Use this method to take hits on a plane. Be sure to hold the mouse steady when holding down the button so that when you release it a valid hit is taken normal to the surface at the pointer's position.

For example, to define a Measured Cone feature in the Z+ view in Curve mode, perform a right-click + drag operation in screen A on the cone's top circle and then left-click on the circle to insert four hits. Right-click + drag again on the bottom circle again in screen A and then left-click again on the circle to insert four more hits. You should have eight hits each at different depths. Press END to create the Measured Cone feature.

Surface Mode

The Surface mode option makes a solid model's surfaces selectable when clicking on the CAD data in the Graphics Display window. You must import a solid model for this option to become available. To take a hit, click on any surface. PC-DMIS pierces the surface, captures the X,Y,Z,I,J,K information, and the hit is recorded at the pointer's position. Select the correct number of hits to define the feature and then press the END key. PC-DMIS will guess the feature type. This mode works best for creating point, line, and plane features. While you can also use this mode with circular features (circles, cylinders, cones, and spheres), you will find that it is often difficult to select hits at a constant cross section or depth, especially for inside features. In these cases you may want to use Curve mode.

For information on using these modes with scans, see the "Scanning your Part" section.