This node generates a mask in the shape of the arc of a circle.

The arc of a circle is defined by 3 points: point 1 and point 3 form the 2 extremities of the arc of a circle, and point 2 adjusts the radius of curvature between the two end points.
Points 1, 2 and 3 can be moved using the manipulators or their X and Y coordinates can be entered manually in the node properties.
The points cannot overlap, i.e. it is impossible to create a closed circle.

If the coordinate values of a point are constrained by a value from an optional input connector, the manipulator associated with these coordinates is not displayed. In the example below, the coordinate values of point 1 come from another node: the manipulator of point 1 no longer appears.

To add an Arc node, right-click in the Graph Editor and select Create Node  > Mask Generation  > Arc or press the keyboard shortcut N-A-R (Node Arc).

Double click on the node to open its parameters:

### Editing an Arc node

To edit the Arc node:

• Preset: List of existing size presets. Select one from the list to apply the size preset.
• Width: Width of the mask to generate in number of vertices.
• Height: Height of the mask to generate in number of vertices.
• Points 1 and 2: These points define the ends of the line. Use the sliders to adjust the point's X and Y coordinates.
The X and Y coordinates of each of the two points are relative to the center of the mask with a value between -1 and +1:
•  0 corresponds to the middle in width (X), in height (Y); (0,0) positions the point in the center of the mask.
• -1 and 1 correspond to the minimum and maximum values of the coordinates (limit of the mask); (1,1), (-1,1), (1,-1), and (1,1) position the point in one of the four corners of the mask.
• Line – Width: Adjusts the thickness of the line from 1 to 20.

### Components

The Line and Arc nodes can be used in components to propagate the coordinates of their respective points, allowing the formation of a circuit. An end point of an Arc can be linked to an end point of Line to guarantee a permanently valid link between the different masks. This is used in the This is used in the Road sample, available in the Help > Samples menu.

Components can be retrieved from this sample project in the Models window > Mask generation > Circuit - Arc or Circuit - Line, and then right-click and select Export component.

### Parameters

Parameter Use
Preset List of existing size presets.
Width Width of the mask to generate in number of vertices.
Height Height of the mask to generate in number of vertices.