This group of options in the main Features Menu are those that are commonly used for line features. Further options relating to line features are to be found in the Lines pop-up menu described in other articles.
The Modify Delete option allows you to delete a line feature from the current model. Indicate the feature and any graphics associated with the feature will be erased. The points used by the feature will be deleted and, if a DTM has been formed, any triangles using those points will be adjusted.
The Modify Remove option allows you to remove a feature from the current model whilst retaining the points that make it. Indicate the feature and any graphics associated with the feature will be erased. The code for each point that makes up the feature will then be set empty. Any dimensions on any of the points will be retained but all comma codes will be removed.
The Modify Close/Open option allows you to toggle a line feature between being an open or a polygon feature. After indicating the feature, it will be checked to see if is closed or not. If it is closed, the closed polygon comma code, normally P, will be removed from either the first or the last point. If it is open, the closed polygon comma code will be added to the last point of the feature.
The Modify Gap option allows you to gap a segment of the line feature. Gapping is carried out when a point on the line feature has a gap comma code, normally G. You will be asked to indicate the segment of the line feature that is not to be displayed and the gap comma code will be applied to the first point on the segment. If you wish to reinstate a line feature segment that has been gapped, you will need to query the point at either end of the gap to find where the gap comma code is and remove it using the Point Properties Dialog Box
The Modify Join option allows you to join two strings together. You will be asked to indicate the end of the first feature and the beginning of the second feature. The two features will then be joined together taking the code and direction from the first indicated feature. If you indicate both ends of an open line feature, the feature will be closed automatically. Note that you cannot join a closed feature to another, whether it is open or closed.