This function will return the bulge value describing an arc which starts at the first supplied point pt1, passes through the second supplied point pt2, and terminates at the third supplied point pt3. Polyline should be divided into equal small parts or based.Īrguments Symbol Type Description pt1, pt2, pt3 List 3 points defining an arc Returns Type Description Real The bulge value describing the arc starting at pt1, passing through pt2, to pt3. In my case I have only one polyline,which may consist af several arc and lines. Learn more about our training for AutoCAD at. The function first normalises the included arc angle to lie within the range 0 ≤ θ.Ĭreating a Polyline with lines and arc segments as a single closed object in AutoCAD 2015. Arguments Symbol Type Description c List Arc Center a1, a2 Real Start and End Angle of Arc (respectively) r Real Arc Radius Returns Type Description List List of: ( ) describing the Polyline Arc This function will convert the quantities used to define an AutoCAD Arc Entity (center, start/end angle, radius) to those used to define a Polyline Arc segment (vertices, bulge). Here I demonstrate various methods to convert between the quantities used to define a Polyline Arc segment and those used to define an Arc Entity, with a brief explanation of calculations used in each method. The arc is always defined to be anticlockwise oriented, that is, following an anticlockwise direction from the start angle to the end angle. An AutoCAD Arc Entity is defined by a center, radius and start & end angle. In this way, a negative bulge indicates that the arc follows a clockwise direction from the first vertex to the next, with a positive bulge describing an anticlockwise oriented arc.Ī bulge of 0 indicates a straight segment, and a bulge of 1 is a semicircle. It is defined as the ratio of the arc sagitta (versine) to half the length of the chord between the two vertices this ratio is equal to the tangent of a quarter of the included arc angle between the two polyline vertices. This unit measures the deviation of the curve from the straight line (chord) joining the two vertices of the segment. Bulge Conversion Functions The curvature of a Polyline Arc segment is defined using a quantity known as bulge.
0 kommentar(er)
