AutoCAD supplies a solid-fill and more than fifty industry-standard hatch patterns. Hatch patterns highlight a particular feature or area of a drawing. For example, patterns can help differentiate the components of a 3D object or represent the materials that make up an object.
You can use a pattern supplied with AutoCAD or one from an external pattern library.
To specify a unique pattern, you must specify both a pattern type and name for the Hatch object. The pattern type specifies where to look up the pattern name. When entering the pattern type, use one of the following constants:
Selects the pattern name from those defined in the acad.pat or acadiso.pat files.
Defines a pattern of lines using the current linetype.
Selects the pattern name from a PAT other than the acad.pat or acadiso.pat files.
When entering the pattern name, use a name that is valid for the file specified by the pattern type.