Masks are limited in that only one inside mask can be defined on each surface and if you use an inside mask you cannot use an outside mask on the same surface.īoundaries can be used to affect the visibility of the surface triangles inside it. Areas that have been masked are included in calculations, such as total area and volume. Masks do not change the surface definition they only affect the visual display of a surface. Masking a surface does not alter the data that is used to create the underlying surface. In addition, when defining a mask as Render Only, the display of the surface is not masked, but when the surface is rendered, the render material pattern is displayed. When you define a mask as an outside type, the portion of the surface residing outside the defined area is hidden. When you define a mask as an inside type, the portion of the surface inside the defined area is hidden. Masks can be defined as either an Inside Mask or an Outside Mask. Masks can be defined from AutoCAD Civil 3D parcels and from polygon-type objects. Masks can be used to block out areas of a surface and prevent them from being displayed or to render a section of the surface using a specified render material. So, which one do we use and what’s the difference? A surface can include both masks and boundaries. Two different ways to accomplish this task are by using a surface mask or a surface boundary.īoth tools can define a surface area we wish to display or exclude and both tools can refine or remove visual elements of the surface.

However, we may want to exclude an area of our surface, such as an area that is beyond a right-of-way or property line.

We may want to alter the contour display in an area, such as a building pad or a detention pond. AutoCAD Civil 3D has many useful tools to alter and refine the output of surface models.

Autocad civil 3d 2014 contour lines