How to Draw Polygons in BricsCAD
Quick answer: A polygon is a closed polyline with anywhere from 3 to 1,024 equal-length sides. Three drawing methods are available: Center-Vertex, Center-Side, and Edge, and unlike most settings, the number of sides doesn’t persist between BricsCAD sessions.
The Three Drawing Methods
- Center-Vertex: define the centre point, then a vertex. This is effectively the radius of the polygon’s circumscribed circle, the circle touching every vertex from outside.
- Center-Side: define the centre point, then the midpoint of a side instead. This is effectively the radius of the polygon’s inscribed circle, the circle touching every side’s midpoint from inside.
- Edge: define the length of one side directly.
Finding the Polygon Tool
The Draw menu, the Draw toolbar, the Draw ribbon panel, or the Draw tab of the No Selection Quad.
Drawing a Polygon: General Procedure
- Launch
POLYGON. You’re prompted to set the number of sides (4 by default), or choose Width of line or Multiple polygons. - Either press Enter or right-click to accept the current number, or type a new value and press Enter. You’re prompted for the centre of the polygon, or to specify by Edge instead.
- Specify a point. You’re prompted to select the midpoint of a side, or specify by Vertex instead.
- Specify a point. The polygon is created.
Two Things Worth Knowing
- Whichever option you choose in step 3, midpoint of side or vertex, gets remembered the next time you run the command.
- The number of sides is controlled by
POLYSIDES, but this value isn’t saved between sessions. Every time you start a new BricsCAD session and runPOLYGONfor the first time, it resets to 4.
Frequently Asked Questions
What’s the maximum number of sides a polygon can have? 1,024. The minimum is 3.
What’s the difference between the Center-Vertex and Center-Side methods? Center-Vertex uses the radius of the polygon’s circumscribed circle (touching every vertex). Center-Side uses the radius of its inscribed circle (touching every side’s midpoint) instead.
Why does my polygon default back to 4 sides every time I restart BricsCAD? That’s expected. POLYSIDES isn’t saved between sessions, so it resets to 4 the first time you run POLYGON in a new session, even if you used a different number last time.
Will BricsCAD remember whether I prefer specifying by vertex or by side midpoint? Yes, that particular choice is remembered from one use of the command to the next, unlike the side count.