> For the complete documentation index, see [llms.txt](https://docs.flatredball.com/gum/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.flatredball.com/gum/gum-tool/gum-elements/skia-standard-elements/arc/start-angle.md).

# Start Angle

### Introduction

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.

<figure><img src="/files/bL6RSoxHmqjMwZq0YNfx" alt=""><figcaption><p>An arc with a Start Angle of 0</p></figcaption></figure>

Changing the Start Angle moves one side of the arc. The arc appears to rotate if the Start Angle is changed gradually.

<figure><img src="/files/bET7pCk2Kr4UzI017Oqp" alt=""><figcaption><p>Changing the Start Angle makes the arc appear to be rotating</p></figcaption></figure>

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.


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