Arc

Arc

An Arc is a continuous slice of a circle described by the position of its center, its radius, and the angles it is drawn between. An Arc draws relative to its center, just like a Circle.

Constructor

new Arc(radius, startAngle, endAngle, angleUnit)

Source:
Constructs a new arc.
Example
// create an Arc with radius 30 with an angle from 0 to -90
const arc = new Arc(30, 0, 90, Arc.DEGREES);
add(arc);
Parameters:
Name Type Description
radius number Desired radius of the arc.
startAngle number Start angle of the arc.
endAngle number End angle of the arc.
angleUnit number Integer representing unit: Degrees:0, Radians:1

Extends

Members

layer

Source:
Overrides:
Sets the layer of the Thing and marks the sortInvalidated flag so any Graphics instances drawing it know to re-sort.

radius :number

Source:
The radius of the arc
Type:
  • number

Methods

containsPoint(x, y) → {boolean}

Source:
Overrides:
Checks if a given point is contained within the arc.
Parameters:
Name Type Description
x number x coordinate of the point being tested.
y number y coordinate of the point being tested.
Returns:
Type
boolean

describe()

Source:
Overrides:
Describes the element for use with screen readers. This isn't something you should need to call manually, but you can if you'd like to print a text descriptino of the Thing.

focus()

Source:
Overrides:
Focuses the element for use with screen readers. This isn't something you should need to call manually, but you can if you'd like to provide focus to an element even if it wasn't navigated to with the keyboard.

getAnchor() → {Object}

Source:
Overrides:
Gets the element's anchor.
Returns:
Type
Object

getBorderColor() → {Color}

Source:
Overrides:
Gets the border color of a Thing.
Example
// this method is on every Shape
let thing = new Thing();
thing.getBorderColor();
Returns:
The color of the Thing's border.
Type
Color

getBorderWidth() → {number}

Source:
Overrides:
Gets the width of the Thing's border.
Example
// this method is on every Shape
let thing = new Thing();
thing.getBorderWidth();
Returns:
The width of the Thing's border.
Type
number

getBounds() → {Object}

Source:
Overrides:
Get the elements bounds. This is an internal property that you shouldn't need to use, but it can be useful for doing quick calculations for the bounding box of a shape.
Example
// this method is on every Shape
let thing = new Thing();
let height = thing.getBounds().bottom - this.getBounds().top;
Returns:
Type
Object

getColor() → {Color}

Source:
Overrides:
Gets the color of a Thing.
Example
// this method is on every Shape
let thing = new Thing();
thing.getColor(); // #000000, by default
Returns:
The destination y coordinate of this Thing.
Type
Color

getEndAngle() → {number}

Source:
Gets the end angle of the arc.
Returns:
Type
number

getStartAngle() → {number}

Source:
Gets the starting angle of the arc.
Returns:
Type
number

getType() → {string}

Source:
Overrides:
Get the .type of the Thing
Returns:
Type
string

getX() → {number}

Source:
Overrides:
Gets the x position of the Thing.
Example
thing.x === thing.getX();
Returns:
The x position of the Thing.
Type
number

getY() → {number}

Source:
Overrides:
Gets the y position of the Thing.
Example
thing.y === thing.getY();
Returns:
The y position of the Thing.
Type
number

hasBorder() → {boolean}

Source:
Overrides:
Returns if a Thing has a border.
Example
// this method is on every Shape
let thing = new Thing();
thing.hasBorder();
Returns:
True if the Thing has a border.
Type
boolean

isFilled() → {boolean}

Source:
Overrides:
Returns if a Thing is filled.
Example
// this method is on every Shape
let thing = new Thing();
thing.isFilled();
Returns:
True if the Thing is filled.
Type
boolean

move(dx, dy)

Source:
Overrides:
Changes the possition of a thing by a specified x and y amount.
Example
// this method is on every Shape
let thing = new Thing();
thing.move(10, 10);
Parameters:
Name Type Description
dx number The resulting change in the Thing's x position.
dy number The resulting change in the Thing's y position.

rotate(degrees, angleUnit)

Source:
Overrides:
Rotates a Thing an additional amount of degrees.
Example
// this method is on every Shape
let thing = new Thing();
thing.rotate(90);
thing.rotate(Math.PI / 2, Thing.RADIANS);
Parameters:
Name Type Description
degrees number The degrees to rotate degrees.
angleUnit number Whether it is degrees or radians. Defaults to degrees.

setAnchor(anchor)

Source:
Overrides:
Sets the Anchor for the object. This alters how the shape will draw relative to its position. An anchor of 0, 0 will cause the shape to draw with its position at its top left corner. An anchor of 1, 1 will cause the shape to draw with its position at its bottom right corner.
Example
// this method is on every Shape
let thing = new Thing();
// center the object around its position
thing.setPosition({vertical: 0.5, horizontal: 0.5});
Parameters:
Name Type Description
anchor Object

setBorder(hasBorder)

Source:
Overrides:
Sets a Thing object to filled. Throws an error if an argument is not passed.
Example
// this method is on every Shape
let thing = new Thing();
thing.setBorder(true);
Parameters:
Name Type Description
hasBorder bool A boolean of whether or not Thing has a border.

setBorderColor(color)

Source:
Overrides:
Sets the border color of a Thing. Throws an error if there are fewer than 1 params or if the param is undefined. This will automatically give the Thing a border, as if you had called thing.setBorder(true);
Example
// this method is on every Shape
let thing = new Thing();
thing.setBorderColor('orange');
Parameters:
Name Type Description
color Color The resulting color of the Thing's border.

setBorderWidth(width)

Source:
Overrides:
Sets the width of a Thing's border. Throws an error if there is not 1 argument. This will automatically set the Thing to draw with a border, as if you had called thing.setBorder(true);
Example
// this method is on every Shape
let thing = new Thing();
thing.setBorderWidth(5);
Parameters:
Name Type Description
width number The resulting width of the Thing's border.

setColor(color)

Source:
Overrides:
Sets the color of a Thing. Throws an error if there are fewer than 1 params or if the param is undefined.
Example
// this method is on every Shape
let thing = new Thing();
thing.setColor('red');
thing.setColor(Color.orange);
thing.setColor('#ff0000');
Parameters:
Name Type Description
color Color The resulting color of Thing.

setDirection(val)

Source:
Gets the direction of the arc (CW or CCW).
Parameters:
Name Type Description
val boolean Boolean representing CW or CCW. `True` sets counterclockwise to true.

setEndAngle(angle)

Source:
Sets the ending angle of the arc. Note: All angles are stored in radians, so we must first convert to radians (if the unit is degrees) before storing the new angle.
Example
const a = new Arc(30, 0, 180, 0);
a.setEndAngle(90);
a.endAngle === Math.PI / 2;
Parameters:
Name Type Description
angle number The desired end angle of the arc.

setFilled(filled)

Source:
Overrides:
Sets a Thing object to filled. Throws an error if an argument is not passed.
Example
// this method is on every Shape
let thing = new Thing();
thing.setFilled(false);
Parameters:
Name Type Description
filled bool A boolean of whether or not Thing is filled.

setOpacity(opacity)

Source:
Overrides:
Set the opacity of the Thing.
Example
// this method is on every Shape
let thing = new Thing();
thing.setOpacity(0.5);
Parameters:
Name Type Description
opacity number

setPosition(x, y)

Source:
Overrides:
Sets the position of a Thing. Throws an error if there are fewer than 2 params or if they are not numbers.
Example
// this method is on every Shape
let thing = new Thing();
thing.setPosition(30, 30);
Parameters:
Name Type Description
x number The destination x coordinate of this Thing.
y number The destination y coordinate of this Thing.

setRotation(degrees, angleUnit)

Source:
Overrides:
Sets the rotation of a Thing in degrees. Throws an error if there are fewer than 1 params or if they are not numbers.
Example
// this method is on every Shape
let thing = new Thing();
thing.setRotation(90);
thing.setRotation(Math.PI / 2, Thing.RADIANS);
Parameters:
Name Type Description
degrees number The degrees to rotate degrees.
angleUnit number Whether it is degrees or radians. Defaults to degrees.

setStartAngle(angle)

Source:
Sets the starting angle of the arc. Note: All angles are stored in radians, so we must first convert to radians (if the unit is degrees) before storing the new angle.
Example
const a = new Arc(30, 0, 180, 0);
a.setStartAngle(90);
a.startAngle === Math.PI / 2;
Parameters:
Name Type Description
angle number The desired start angle of the arc.

setType(type)

Source:
Overrides:
Set the .type of the Thing
Parameters:
Name Type Description
type string new type

unfocus()

Source:
Overrides:
Unfocuses the element for use with screen readers. This isn't something you should need to call manually, but you can if you'd like to unfocus to an element even if it wasn't navigated from with the keyboard.