IShape
Interface representing a shape that can be rendered on a canvas.
This interface defines methods for rendering the shape on a canvas and managing observers.
Accessors
state
Get Signature
get state():
ShapeState
Gets the current state of the shape.
Returns
The current state of the shape.
Set Signature
set state(
state):void
Sets a new state for the shape.
Parameters
• state: ShapeState
The new state to assign to the shape.
Returns
void
Defined in
stateStyle
Get Signature
get stateStyle():
IShapeStyle
Retrieves the effective style of the shape based on its current state.
Returns
The computed style object for the current shape state, with state-specific overrides merged in as necessary.
Defined in
Methods
addObserver()
addObserver(
observer):void
Adds an observer function that will be called when the shape undergoes changes.
Parameters
• observer
A callback function to be invoked when the shape's state changes.
Returns
void
Defined in
hide()
hide():
void
Hides the shape, preventing it from being rendered on the canvas.
The shape will still exist and retain its properties, but it will not
appear during rendering until show() is called.
Returns
void
Defined in
isDraggable()
isDraggable():
boolean
Checks whether the shape is draggable or not.
Returns
boolean
Returns true if the shape is draggable. Returns false if the shape is not draggable.
Defined in
isMouseOver()
isMouseOver(
mousePosition):boolean
Determines if the mouse is currently over the shape.
Parameters
• mousePosition: Point
The current mouse position.
Returns
boolean
True if the mouse is over the shape, false otherwise.
Defined in
isVisible()
isVisible():
boolean
Checks whether the shape is currently visible.
Returns
boolean
Returns true if the shape is visible and will be rendered on the canvas. Returns false if the shape is hidden and will not be rendered.
Defined in
onDrag()
onDrag(
delta):void
Handles the drag operation by applying the given delta to the current position.
Parameters
• delta: Point
The change in position represented as a Point.
Returns
void
Defined in
removeObserver()
removeObserver(
observer):void
Removes an observer function that was previously added.
Parameters
• observer
The observer callback function to be removed.
Returns
void
Defined in
render()
render(
context):void
Renders the shape to a given canvas context.
Parameters
• context: CanvasRenderingContext2D
The 2D rendering context of the canvas where the shape will be drawn.
Returns
void
Defined in
show()
show():
void
Makes the shape visible, allowing it to be rendered on the canvas. If the shape was previously hidden, calling this method will make it appear during the next rendering cycle.
Returns
void