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arc method

Adds points to a path that represents an arc.

 

Syntax

object.arc(x, y, radius, startAngle, endAngle, anticlockwise);

Parameters

x [in]

Type: number

The x-coordinate, in pixels, for the center point of the arc in relation to the upper-left corner of the canvas rectangle.

y [in]

Type: number

The y-coordinate, in pixels, for the center point of the arc in relation to the upper-left corner of the canvas rectangle.

radius [in]

Type: number

The radius or distance from the point (x,y) that the arc's path follows.

startAngle [in]

Type: number

The starting angle, in radians, where 0 is at the 3 o'clock position of the arc's circle.

endAngle [in]

Type: number

The ending angle, in radians.

anticlockwise [in]

Type: BOOL

true

The arc is drawn in a counterclockwise direction from start to end.

false

The arc is drawn in a clockwise direction from start to end.

Return value

This method does not return a value.

Exceptions

Exception Condition
IndexSizeError

The specified radius value is negative.

 

Standards information

Remarks

If the startAngle and endAngle angles are equal, the ICanvasRenderingContext2D::arc method creates a circle. To convert degrees to radians use the following formula.

var radians = degrees * Math.PI/180