Draw Polyline Arcs

A polyline is a connected sequence of line segments created as a single object. You can create straight line segments, arc segments, or a combination of the two.
Multisegmented lines provide editing capabilities unavailable for single lines. For example, you can adjust their width and curvature. After you've created a polyline, you can edit it with PEDIT or use EXPLODE to convert it to individual line and arc segments. You can
Convert a spline-fit polyline into a true spline with SPLINE
Use closed polylines to create a polygon
Create a polyline from the boundaries of overlapping objects
Create Arc Polylines
When you draw arc segments in a polyline, the first point of the arc is the endpoint of the previous segment. You can specify the angle, center point, direction, or radius of the arc. You can also complete the arc by specifying a second point and an endpoint.

Create Closed Polylines
You can draw a closed polyline to create a polygon. To close a polyline, specify the starting point of the last side of the object, enter c (Close), and press ENTER.
Create Wide Polylines
You can draw polylines of various widths by using the Width and Halfwidth options. You can set the width of individual segments and make them taper gradually from one width to another. These options become available after you specify a starting point for the polyline.
The Width and Halfwidth options set the width of the next polyline segments you draw. Zero (0) width produces a thin line. Widths greater than zero produce wide lines, which are filled if Fill mode is on and outlined if Fill mode is off. The Halfwidth option sets width by specifying the distance from the center of the wide polyline to an outside edge.
Taper
When you use the Width option, AutoCAD LT prompts for both a starting and an ending width. By entering different values, you can taper the polyline. The starting and ending points of wide polyline segments are in the center of the line. Intersections of adjacent wide segments are usually beveled. However, AutoCAD LT does not bevel nontangent arc segments, acute angles, or segments that use a dash-dot linetype.
Create Polylines from the Boundaries of Objects
You can create a polyline from the boundaries of overlapping objects that form a closed area. A polyline created using the boundary method is a separate object, distinct from the objects used to create it. You can edit it using the same methods used to edit other polylines.
To expedite the boundary selection process in large or complex drawings, you can specify a group of boundary candidates, called a boundary set. You create this set by selecting the objects you want AutoCAD LT to examine as it defines the boundary.

To draw a line and arc combination polyline
From the Draw menu, choose Polyline.
Specify the start point of the polyline segment.
Specify the endpoint of the polyline segment.
Switch to Arc mode by entering a (Arc) on the command line.
Return to Line mode by entering L (Line).
Specify additional polyline segments as needed.
Press ENTER to end or c to close the polyline.
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Set the Current Color

You can use color to help you group objects visually. You can assign the color of an object either by layer or by specifying its color explicitly, independent of layer. Assigning colors by layer makes it easy to identify each layer within your drawing. Assigning colors explicitly provides additional distinctions between objects on the same layer. Color is also used as a way to indicate lineweight for color-dependent plotting.

ACI Colors
ACI colors are the standard colors used in AutoCAD LT. Each color is identified by an ACI number, an integer from 1 through 255. Standard color names are available only for colors 1 to 7. The colors are assigned as follows: 1 Red, 2 Yellow, 3 Green, 4 Cyan, 5 Blue, 6 Magenta, 7 White/Black.
All objects are created using the current color, which is displayed in the Color control on the Properties toolbar. You can also set the current color with the Color control or the Select Color dialog box.

If the current color is set to BYLAYER, objects are created with the color assigned to the current layer. If you do not want the current color to be the color assigned to the current layer, you can specify a different color.
If the current color is set to BYBLOCK, objects are created using color 7 (white or black) until the objects are grouped into a block. When the block is inserted into the drawing, it acquires the current color setting.

To set an ACI color for all new objects

On the Properties toolbar, click the Color control.
Click a color to draw all new objects in that color, or click Select Color to display the Select Color dialog box and do one of the following:
On the Index Color tab, click a color or enter the color name or number in the Color box.
On the Index Color tab, click BYLAYER to draw new objects in the color assigned to the current layer.
On the Index Color tab, click BYBLOCK to draw new objects in the current color until they are grouped into a block. When the block is inserted into the drawing, the objects in the block acquire the current color setting.
Click OK.
The Color control displays the current color.
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Overview of Coordinate Entry

When a command prompts you for a point, you can use the pointing device to specify a point, or you can enter a coordinate value on the command line. You can enter two-dimensional coordinates as either Cartesian (X,Y) or polar coordinates. Cartesian and Polar Coordinates A Cartesian coordinate system has three axes, X, Y, and Z. When you enter coordinate values, you indicate a point's distance (in units) and its direction (+ or -) along the X, Y, and Z axes relative to the coordinate system origin (0,0,0). In 2D, you specify points on the XY plane, also called the construction plane. The construction plane is similar to a flat sheet of grid paper. The X value of a Cartesian coordinate specifies horizontal distance, and the Y value specifies vertical distance.

The origin point (0,0) indicates where the two axes intersect. Polar coordinates use a distance and an angle to locate a point. With both Cartesian and polar coordinates, you can enter absolute coordinates based on the origin (0,0), or relative coordinates based on the last point specified. Another method of entering a relative coordinate is by moving the cursor to specify a direction and then entering a distance directly. This method is called direct distance entry. You can enter coordinates in scientific, decimal, engineering, architectural, or fractional notation. You can enter angles in grads, radians, surveyor's units, or degrees, minutes, and seconds. You specify the unit style in the Units Control dialog box.
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