Defining a hatch pattern requires knowledge, practice, patience, and a text editor. You can add a pattern to the acad.pat library file or store it in a file by itself, in which case the file name must be the same as the pattern name. For instance, a pattern named PIT would reside in the pit.pat file.
Regardless of where the definition is stored, the pattern has the same format. It has a header line that looks like this:
*pattern-name [, description]
It also has one or more line descriptors of the following form:
angle, x-origin, y-origin, delta-x, delta-y [, dash-1, dash-2, ...]
For example, a pattern called L45 that hatches with 45-degree lines separated by a spacing of 0.5 is defined as follows:
*L45,45 degree lines
45, 0,0, 0,0.5
This simple pattern specifies that a line is to be drawn at an angle of 45 degrees, that the first line of the family of hatch lines is to pass through the (0,0) drawing origin, and that the spacing between hatch lines of the family is to be 0.5 drawing units. L45 is the name of the pattern, and the description field is the optional description of the pattern displayed by the ? option of theHATCH command. (If you omit the description, do not include a comma after the pattern name.)
Each line in a pattern definition file can contain up to 80 characters. AutoCAD ignores blank lines and text to the right of a semicolon.
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Regardless of where the definition is stored, the pattern has the same format. It has a header line that looks like this:
*pattern-name [, description]
It also has one or more line descriptors of the following form:
angle, x-origin, y-origin, delta-x, delta-y [, dash-1, dash-2, ...]
For example, a pattern called L45 that hatches with 45-degree lines separated by a spacing of 0.5 is defined as follows:
*L45,45 degree lines
45, 0,0, 0,0.5
This simple pattern specifies that a line is to be drawn at an angle of 45 degrees, that the first line of the family of hatch lines is to pass through the (0,0) drawing origin, and that the spacing between hatch lines of the family is to be 0.5 drawing units. L45 is the name of the pattern, and the description field is the optional description of the pattern displayed by the ? option of theHATCH command. (If you omit the description, do not include a comma after the pattern name.)
Each line in a pattern definition file can contain up to 80 characters. AutoCAD ignores blank lines and text to the right of a semicolon.
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