Drawing arcs by edges

You can construct an arc by consecutively positioning three points (starting, middle and end) that lie on the arc curve, the center of the circle the arc belongs to, and the radius of the arc and the angle between the two radii connecting the center with the starting and the end points of the arc, respectively.

NOTE: In this mode, the middle point does not denote the midpoint of the arc's circumferential length.

The contextual edit bars

In the process of drawing and when selected:

For help on this functionality, see Snapping objects.

Starts the Detect Relations Manager.

Relative Dx and Dy while repositioning the arc:

Attributes

• Radius. Appears as Radius in the contextual edit bar, and as r=... in the Data column in the tabular area.
• Angle. The angle between the two radii connecting the center with the beginning and the end points of the arc, respectively. Appears as Angle in the contextual edit bar, and as sweep=... in the Data column in the tabular area.
• Length. This is the circumferential length of the arc curve. Appears in the Length column in the tabular area.
• Relative Dx and Dy. Appear on the contextual edit bar only while you are repositioning an arc by dragging. Dx and Dy are the relative horizontal/vertical offset distances between the original and the repositioned arc locations as projected on the x-axis and y-axes. The Dx/Dy values are, respectively, the Ox/Oy coordinate position of the repositioned arc less the proportional Ox/Oy coordinate position of the original arc.
• Style. For more about styles, see Formatting styles, colors and templates.
• Id. A system-generated, unique object identification number. Appears in the Id column in the tabular area.

Control points

An arc by edges has four control points: starting, middle and end points, which lie on the arc's curve, and the center point of the circle the arc belongs to. While you are drawing an arc by edges, the following pointers appear:

About to draw the starting point.

About to draw the middle point.

About to draw the end point.

Tabular presentation

When you have finished drawing an arc, its object type, Id number, circumferential length, radius, angle (sweep) and style are recorded in the Objects tab in the tabular area.

The data in the Objects tab is unavailable for direct editing.

To draw an arc by edges

1. Do any of the following:

• On the Objects toolbar, click Arc by Edges .
• On the Objects menu, point to Arcs, and then click Arc by Edges.
• Press CTRL+D+A+3.

2. (Optional) Snap the starting point of the arc to another object or point.
3. Place the starting point of the arc.
4. (Optional) Snap the middle point of the arc that you are about to place, to another object or point.
5. Place the middle point of the arc.
6. To finish the arc:

• Snap the end point of the arc, or point to where you want the end point of the arc to be, and then click it.
• In the contextual edit bar, in Radius and Angle, enter values you want, press ENTER, and then in the graphical area, click anywhere.

To modify an arc by changing its attributes

1. Select the arc.
2. In the contextual edit bar, enter attribute values, and then press ENTER.

To reposition an arc by dragging

1. Select the arc.
2. Do any of the following:

• Drag the arc to where you want it to be.
• In the contextual edit bar, in Dx and Dy, enter offset distances relative to the original location of the arc.

3. Click to place the arc in its new location.

NOTE: If the arc's control points coincide with the control points of other objects — for example, when the arc is part of a design box or is connected to another object — EngView repositions the arc and modifies the connected objects depending on the direction and distance at which you drag the arc.