How to Use Entity Linetypes in BricsCAD

Quick answer: A linetype is a repeating pattern of dots, dashes, or blank spaces that differentiates one line’s purpose from another, affecting both screen display and printing. Every drawing has at least three built-in linetypes, Continuous, ByLayer, and ByBlock, plus room for as many named ones as you need.

What Linetypes Are

Linetype definitions save with the drawing. New ones come from either importing them from another drawing or loading them from a .lin file. Which source file loads by default depends on MEASUREMENT: on uses Iso.lin (definitions in mm), off uses Default.lin (definitions in inches). CELTYPE sets the current linetype for new entities.

The Three Linetype Options

• ByLayer: entities take on their layer’s linetype, so changing the layer’s linetype changes every entity using it at once.
• ByBlock: entities draw as continuous lines until they’re included in a block; once that block is inserted into a drawing, they inherit the block entity’s own linetype setting.
• Named linetype: Continuous, or any specific linetype saved in the drawing.

Linetype Scale

Non-continuous linetypes are built from lines, gaps, and dots in a pattern, complex ones can even include text or shapes. Pattern lengths are defined in either inches (default.lin) or mm (iso.lin), so if your drawing units are neither, linetypes need scaling. LTSCALE handles this, set relative to your drawing units:

BricsCAD always places a dash at the start and end of a line, polyline, arc, or spline, and centres the pattern so both ends look symmetrical.

Polyline Generation

Linetypes normally generate vertex to vertex along a polyline. If vertices sit very close together, the pattern might not fit between them and the line renders as continuous instead. Set PLINEGEN to 1 (on) to draw the linetype from one end of the polyline to the other instead, rather than segment by segment.

Linetype Scale in Paper Space and Model Space

• PSLTSCALE: controls linetype scaling in paper space layouts. On, scaling stays independent of the viewport scale, generally the recommended setting, and it can be set per layout.
• MSLTSCALE: controls linetype scaling in model space. On, the current annotation scale (CANNOSCALE) applies to linetypes there. Best left off generally, though switching it on can help when printing directly from model space.

Setting the Current Linetype

Any of these:

• With nothing selected, choose Linetype in the Properties panel and pick from the dropdown.
• On the Entity Properties toolbar, click the down arrow beside the Linetype field.
• Right-click the Linetype field in the Status Bar and choose from the context menu.

Adding a New Linetype

1. Either run LINETYPE and choose New, or select Linetype in the Properties panel, click the down arrow, and choose Load…. The Load linetypes dialog opens.
2. Optionally click File… to load a different source file.
3. Select one or more linetypes; hold Ctrl to add or remove from your selection.
4. Click OK.

Setting the Entity Linetype Scale

1. With nothing selected, choose Linetype scale in the Properties panel.
2. Type a new value.

This saves via CELTSCALE, best left at 1 except for special linetypes like BATTING or GAS_LINE, which typically need their own scaling. It only affects new entities going forward, not existing ones.

Frequently Asked Questions

What’s the difference between ByLayer and ByBlock linetypes? ByLayer inherits whatever linetype the entity’s layer is set to. ByBlock draws as continuous until the entity is placed inside a block, then it inherits that block’s own linetype once inserted.

Why does my polyline look like a solid line instead of dashed? Its vertices are likely too close together for the pattern to fit between them. Turn on PLINEGEN to generate the linetype across the whole polyline instead of vertex to vertex.

Should PSLTSCALE and MSLTSCALE be set the same way? Not necessarily. PSLTSCALE is generally best kept on, while MSLTSCALE is generally best kept off, though switching the latter on can help when printing directly from model space.

Does changing the linetype scale affect entities I’ve already drawn? No, the entity linetype scale set via the Properties panel only applies to new entities from that point on.