Class CanvasSource

Index

Constructors

Accessors

context height offset sizeScaler width

Methods

clear createRegion invalidateContext setLogicalSize toAbsPoint toAbsRect toRelPoint

Constructors

constructor

new CanvasSource(
canvasElementOrQuery: string | HTMLCanvasElement,
sizeBasis?: "max" | "min",
): CanvasSource
Parameters
- canvasElementOrQuery: string | HTMLCanvasElement
- sizeBasis: "max" | "min" = ...
Returns CanvasSource

Accessors

context

get context(): CanvasRenderingContext2D
Returns CanvasRenderingContext2D

height

get height(): number
Returns number

offset

get offset(): { x: number; y: number }
Returns { x: number; y: number }

sizeScaler

get sizeScaler(): { abs: NumberScaler; rel: NumberScaler }
Returns { abs: NumberScaler; rel: NumberScaler }

width

get width(): number
Returns number

Methods

clear

clear(): void
Returns void

createRegion

createRegion(spec: CanvasRegionSpec): CanvasRegion
Creates a region

Absolute positioned. Uses source coordinates which don't change
```
source.createRegion({ 
 absPositioned: { x: 0, y: 0, width: 100, height: 100} 
});
```
Relative positioned. Uses coordiantes relative to source dimensions. Updated if source changes.
```
source.createRegion({
 relativePositioned: { x: 0, y:0, width: 1, height: 0.5 },
 scale: `independent`
});
```
Relative sized. Uses size relative to source dimension. By default centers.
```
source.createRegion({
 relativeSize: { width: 0.5, height: 0.5 }
 position: `center`
})
```
Parameters
- spec: CanvasRegionSpec
Returns CanvasRegion

invalidateContext

invalidateContext(): void
Returns void

setLogicalSize

setLogicalSize(size: Geometry.Rect): Geometry.Rect
Parameters
- size: Geometry.Rect
Returns Geometry.Rect

toAbsPoint

toAbsPoint(pt: Geometry.Point, kind?: "independent"): { x: number; y: number }
Parameters
- pt: Geometry.Point
- kind: "independent" = ...
Returns { x: number; y: number }

toAbsRect

toAbsRect(
    rect: Geometry.Rect | Geometry.RectPositioned,
    kind?: "independent",
):
    | { height: number; width: number; x: number; y: number }
    | { height: number; width: number }
Parameters
- rect: Geometry.Rect | Geometry.RectPositioned
- kind: "independent" = ...
Returns
| { height: number; width: number; x: number; y: number }
| { height: number; width: number }

toRelPoint

toRelPoint(
    pt: Geometry.Point,
    source: "source" | "screen",
    kind?: "independent" | "skip",
    clamped?: boolean,
): { x: number; y: number }
Parameters
- pt: Geometry.Point
- source: "source" | "screen"
- kind: "independent" | "skip" = ...
- clamped: boolean = true
Returns { x: number; y: number }