The options form allows you to specify whether you want to view the video tutorials online or using a local copy on your computer. The video to the right demonstrates how this Options feature works. It is also explained in more detail on the Video Tutorials page.
The one setting available on the advanced tab controls the initial length of cross section lines when they are laid out during the Cross Section Tool.
The Cross Section Tool works by laying out initial, prototype lines perpendicular to the centerline(s). These prototype lines are then clipped to the channel polygon to ensure that the resultant cross cross sections terminate precisely at the extent of the channel.
The initial length of the prototype lines is determined by the setting on the advanced tab on the options form. The value represents the distance from the centerline to the edge of the channel polygon (i.e. half the channel width). If you are using the Cross Section Tool for wide channels and the tool is producing lines that terminate inside the channel polygon then you can increase the initial cross section length to produce longer prototype lines that extend beyond the channel polygon so that they clip correctly.
Use caution when changing the initial cross section length on sinuous channels. Tight bends might result in the prototype lines spanning to parts of the same channel. When they are clipped down, each line could have multiple segments within the channel that confuse the rest of the layout process.
If you are unable to find an initial cross section length that correctly layouts cross sections, then choose a short length (similar to the narrowest width of the channel) and then use ArcGIS Edit tools to manually adjust the short cross section lines produced by the tool. Keep the following in mind when editing cross sections:
- keep the cross sections perpendicular to the centerline.
- Snap the cross section ends to the channel boundary.
- Do not use multi-part lines.
- Cross sections should never cross each other.
- Use continuous cross section lines that pass over top of non-qualifying islands.