Many users run into issues when trying to draw flat objects while dealing with 3D content. Sometimes you might want to snap to a 3D object, but use zero elevation.
There are several ways to make this process as painless as possible:
- AutoCAD objects such as lines and polylines can be flattened with the FLATTEN command from the express tools tab modify panel. When working in programs such as Civil 3D make sure you don’t accidentally flatten contours that are used to build a surface.
- In the options menu under drafting check the replace Z value with current elevation. This option will replace the z value with the 0 value based on your ucs.
- When working in Civil 3D you may adjust your styles so that the contours and points are automatically flattened.
Under point style 3D Geometry you can set point display mode to flatten points to elevation.
Under surface style Borders, Contours, and Triangles each have a 3D display mode vale that can also be set to flatten.
Using these will help prevent users from snapping to elevations other than 0.Note: feature lines do not have any such option, so users may still have issues when snapping to feature lines or grading.