The crop region defines the boundaries for a project view.
You can display a model crop region and an annotation crop region in all graphical project views. Perspective 3D views do not support the annotation crop region.
To work with crop regions, you can
The model crop region crops model elements, detail elements (such as insulation and detail lines), at the model crop boundary.
The 2d extents of datum elements (levels and grids) are automatically resized to the edges of the crop boundary when the 3d extents cross the model crop region. Datum elements are not resized when you turn off the crop region, (the Do Not Crop View option) datums display at the original size they were drawn.
An annotation crop region fully crops annotation elements when it touches any portion of the annotation element, so that no partial annotations are drawn. Annotations (such as symbols, tags, keynotes, and dimensions) that reference hidden or cropped model elements do not display in the view, even if they are inside the annotation crop region. For example, if a door has been cropped from the view by the model crop, the door tag will not be visible even if it is positioned inside the annotation crop.
The annotation crop does not display by default when you show crop regions in a primary view. The annotation crop does display by default when you show crop regions in dependent views or callout views.