Working with an Arc Object on a Schematic Sheet in Altium Designer

Parent page: Schematic Objects

Two placed Arcs (the one on the right is a Full Circle Arc)

Summary

An Arc is a non-electrical drawing primitive. It is essentially a curved line segment that can be used when creating graphical symbols, custom sheet borders and title blocks, etc. A placed Circle is an Arc object that spans 360° (has the same start and end angle).

Availability

Arcs are available for placement in both Schematic and Schematic Library Editors:

• Schematic Editor - the following commands are available:
  • Choose Place » Drawing Tools » Arc from the main menus to place an arc with full control over start and end angles.
  • Choose Place » Drawing Tools » Full Circle from the main menus to place a full circle arc where start and end angles are fixed at 0° and 360°.
  • Click the Arc button () or Full Circle button () in the graphic objects drop-down on the Active Bar located at the top of the workspace. Click and hold or right-click an Active Bar button to access other related commands. Once a command has been used, it will become the topmost item on that section of the Active Bar.
  • Right-click in the workspace then choose Place » Drawing Tools » Arc or Place » Drawing Tools » Full Circle from the context menu.
• Schematic Library Editor - the following commands are available:
  • Choose Place » Arc from the main menus to place an arc with full control over start and end angles.
  • Choose Place » Full Circle from the main menus to place a full circle arc where start and end angles are fixed at 0° and 360°.
  • Click the Arc button () or Full Circle button () in the graphic objects drop-down on the Active Bar menu, located at the top of the workspace. Click and hold or right-click an Active Bar menu button to access other related commands. Once a command has been used, it will become the topmost item on the Active Bar menu.
  • Right-click then choose Place » Arc or Place » Full Circle from the context menu.

Placement

After launching the command, the cursor will change to a cross-hair indicating arc placement mode. Placement is made by performing the following sequence of actions:

1. Click or press Enter to anchor the center point of the arc.
2. Move the cursor to adjust the radius of the arc, then click or press Enter to set it.
3. Move the cursor to adjust the start angle for the arc, then click or press Enter to anchor it.
4. Move the cursor to adjust the end angle for the arc, then click or press Enter to anchor it and complete placement of the arc.
5. Continue placing further arcs or right-click or press Esc to exit placement mode.

Additional actions that can be performed during placement while the arc is still floating on the cursor and before the center point of the arc is anchored are:

• Press the Tab key to pause the placement and access the Arc mode of the Properties panel, from where its line properties can be changed on-the-fly. Click the workspace pause button overlay ( ) to resume placement.
• Press the Alt key to constrain the direction of movement to the horizontal or vertical axis depending on the initial direction of movement. 
• Press the Spacebar to rotate the arc counterclockwise or Shift+Spacebar for clockwise rotation. Rotation is in increments of 90°.
• Press the X or Y keys to mirror the arc along the X-axis or Y-axis.

Graphical Editing

This method of editing allows you to select a placed arc object directly in the workspace and change its size, shape or location graphically.

When an arc object is selected, the following editing handles are available:

Selected Arcs (Full Circle Arc on right).

• Click and drag A to adjust the radius.
• Click and drag B to adjust the arc end points (start and end angles).
• Click on the arc line – away from editing handles – and drag to reposition it. While dragging, the arc can be:
  • rotated (Spacebar for clockwise and Shift+Spacebar for counterclockwise) about the cursor.
  • mirrored (X or Y keys to mirror along the X-axis or Y-axis) relative to the cursor position.
  • moved in only the X or Y plane (hold Alt), depending on which direction the cursor is first moved from its starting point.
  • duplicated (hold Shift, then drag) to a new Arc object.

Non-Graphical Editing

The following methods of non-graphical editing are available:

Via the Arc Dialog or Properties Panel

Properties page: Arc Properties

This method of editing uses the associated Arc dialog mode and Properties panel mode to modify the properties of an arc object.

  The Arc dialog, on the left, and the Arc mode of the Properties panel on the right

After placement, the Arc dialog can be accessed by:

• Double-clicking on the placed arc object.
• Placing the cursor over the arc object, right-clicking then choosing Properties from the context menu.

During placement, the Arc mode of the Properties panel can be accessed by pressing the Tab key. Once the arc is placed, all options appear.

After placement, the Arc mode of the Properties panel can be accessed in one of the following ways:

• If the Properties panel is already active, by selecting the arc object.
• After selecting the arc object, select the Properties panel from the Panels button in the bottom right section of the workspace, or by selecting View » Panels » Properties from the main menu.

The Properties panel supports multiple object editing, where the property settings that are identical in all currently selected objects may be modified. When multiples of the same object type are selected manually, via the Find Similar Objects dialog or through a Filter or List panel, a Properties panel field entry that is not shown as an asterisk (*) may be edited for all selected objects.

The panel with two arc objects selected. Only the X position and Start Angle properties differ and are not editable.

Via a List Panel

Panel pages: SCH List, SCHLIB List, SCH Filter, SCHLIB Filter

A List panel displays design object types from one or more documents in tabular format, enabling quick inspection and modification of object attributes.

Used in conjunction with appropriate filtering – by selecting object types (using the panel's Include options), or by using the applicable Filter panel or the Find Similar Objects dialog – it enables the display of just those objects falling under the scope of the active filter. The properties for the listed objects may then be edited directly in the List panel.