linetypes

Linertypes, in the context of computer-aided design and vector graphics, are predefined patterns used to render lines. They extend the basic solid line by repeating a sequence of visible and invisible segments along the line, allowing different meanings or features to be conveyed in drawings.

A linetype is typically composed of a name and a pattern. The pattern is defined as a sequence of on (drawn) and off (gap) lengths that repeat along the length of the line. In many systems, patterns can be simple (for example, a dash or a dot) or more complex, and some environments support patterns that include shapes or text aligned with the line. The pattern lengths are expressed in drawing units, and the overall appearance can be affected by scaling.

Scale settings determine how large or small the pattern appears. There is often a global linetype scale and, in some contexts, separate scales for model space and paper space or viewports. Adjusting the scale helps ensure that line types read consistently at different zoom levels or print sizes.

Usage is common in architectural, civil, and mechanical drawings to distinguish features such as hidden edges, centerlines, cutting planes, boundaries, or construction lines. Common examples include solid, dashed, dotted, dash-dot, and dash-dot-dot patterns.

Creation and management involve defining new patterns or loading existing libraries, typically stored in files specific to the software (for example, pattern definitions in a lin file). Some programs support complex linotypes with embedded shapes or text, enabling more descriptive line appearances. Linetypes contribute to the clarity and interpretability of technical drawings.