Start Angle defines the angle of the starting point of the arc. This value is measured in degrees, with a value of 0 pointing to the right. The value increases counterclockwise. the Start Angle and Sweep Angle values combine to determine the range of angles covered by the Arc.
The following image shows the an Arc with a Start Angle of 0. The red lines and text are not part of the arc and are added to the screen shot to show the location of the Start Angle.
Changing the Start Angle moves one side of the arc. The arc appears to rotate if the Start Angle is changed gradually.
Start Angle defines the starting point of the arc. A value of 270 degrees and a value of -90 place the starting point of the arc in the same location. Values larger than 360 result in the value looping. These values, although normally not needed, can be used to create spinning animatoins.
Arcs are curved lines with variable thickness. Arcs can also be used to draw wedges if the line thickness is large enough.
Arcs draw inside their bounds, with the edge of the arc touching the bounding rectangle. The thickness of the arc remains consisntent regardless of the bound width and height.
The following shows an arc with a Sweep Angle of 270 degrees, being resized in the Editor tab.
Thickness controls the width of the arc line in pixels. This value can be increased to make the line arc thicker.
Thickness can be increased to create a wedge.
Note that Thickness can be increased to any value including values larger than the radius of the arc. Large values can result in the arc rendering past its center point creating a bowtie shape.
Other undesirable rendering effects can happen with large thicknesses when working with arcs which have one size (width or height) larger than the other, as shown in the following image:
