Curve Segment Codes

Begin Curve: code used to specify that the current point is the beginning of a single curve (arc) segment or multiple curve segments.

EP1 BC

EP1 is the active figure name and is continued to the current point, “ “ (space) is the Feature/Code Delimiter, BC indicates that the current point is the beginning of curve segments.

The current point with this code is the first point on the curve. The next point with the same figure name is considered a point on the curve, and the third point with the same figure name is the curve endpoint if no <End curve> code is used to correspond with the <Begin curve> code.

Circle: code that indicates the beginning of the circle feature. This code stops the linework on the previous point if it is a two or three-point circle.

A one point circle with a radius value is similar to the connect point command. The linework code stops and a new circle is created using the point as the center point and the radius. The two and three-point circles behave like begin commands to create a new figure and end an active feature with the same name.

POOL CIR5.0

POOL is the figure name, “ “ (space) is the Feature/Code Delimiter, CIR is the <Circle> code, and creates a new circular figure where the current point is the radius point, and 5.0 is the circle radius value. The elevation of the figure is the elevation of the current point. This example uses only the current point as the center point, with the <Circle> code followed immediately by the radius.

Method 1 uses only the current point as the center point, with the <Circle> code followed immediately by the radius.

Method 2 uses two consecutive points to define the circular figure. The first point defines the center location and the second point defines the elevation and the radius.

Method 3 uses three points to define a circular figure. The elevation of all three points is used and continues the closure with an arc instead of a line.

Curve Fit - No curve: In the following illustration, each survey point has the same EP1 figure name and are line points (no <Point on curve> code indicating a curve point, or <Begin curve> code). The resulting figure is a series of connected line segments.

Curve Fit - Three-point curve: In the following illustration, each point has the same EP1 figure name, and there is three consecutive curve points (OC <Point on curve> code, or BC <Begin curve> code at the beginning of the curve). The resulting figure will have a begin curve (BC) at the first EP1 point, an end curve (EC) at the third EP1 point, and the curve will pass through the second EP1 point.