Type Property 型プロパティ

luminanceToAlpha

Returns a filter that sets the opacity of each pixel based on its luminance.

Declaration 宣言 

static var luminanceToAlpha: GraphicsContext.Filter { get }

Return Value 戻り値

A filter that applies a luminance to alpha transformation.

Discussion 議論

The filter computes the luminance of each pixel and uses it to define the opacity of the result, combined with black (zero) color components.

See Also 参照

Adjusting Opacity

static func alphaThreshold(min: Double, max: Double, color: Color) -> GraphicsContext.Filter
Returns a filter that replaces each pixel with alpha components within a range by a constant color, or transparency otherwise.