# PKInkingToolReference An object that defines the drawing characteristics (width, color, pen style) to use when drawing lines on a canvas view. ``` class PKInkingToolReference ``` ## Overview A [`PKInkingTool`](/documentation/PencilKit/PKInkingTool-swift.struct) object supports the creation of new content on a [`PKCanvasView`](/documentation/PencilKit/PKCanvasView). With an inking tool, the canvas turns touch input from the user into a continuously rendered stroke. The value in the [`width`](/documentation/PencilKit/PKInkingToolReference/width) property determines the base width of that stroke; however, that base value also depends on input from Apple Pencil, including force, azimuth, and angle data. Create an inking tool programmatically, or display a [`PKToolPicker`](/documentation/PencilKit/PKToolPicker) object and from which a user can select a tool. Assign the resulting object to the [`tool`](/documentation/PencilKit/PKCanvasView/tool-6str6) property of your [`PKCanvasView`](/documentation/PencilKit/PKCanvasView) object. The canvas uses any subsequent touch sequences to draw new content on the canvas. Assigning a new inking tool doesn’t change the characteristics for any previously drawn strokes. ## Topics ### Creating an inking tool [`init(inkType: __PKInkType, color: UIColor, width: CGFloat)`](/documentation/PencilKit/PKInkingToolReference/init(inkType:color:width:)) Creates an ink tool object with the specified color and line width values. [`convenience init(inkType: __PKInkType, color: UIColor)`](/documentation/PencilKit/PKInkingToolReference/init(inkType:color:)) Creates an ink tool object with the default line width and the specified color. [`convenience init(ink: PKInk, width: CGFloat)`](/documentation/PencilKit/PKInkingToolReference/init(ink:width:)) Create an inking tool with the specified ink and width. ### Getting the inking tool attributes [`var color: UIColor`](/documentation/PencilKit/PKInkingToolReference/color) The color of the ink. [`var width: CGFloat`](/documentation/PencilKit/PKInkingToolReference/width) The base line width for new content. [`var ink: PKInk`](/documentation/PencilKit/PKInkingToolReference/ink) The ink that this tool creates strokes with. ### Getting the tool type [`var inkType: __PKInkType`](/documentation/PencilKit/PKInkingToolReference/inkType) The tool type that determines the shape of the rendered content. [`typedef NSString * PKInkType;`](/documentation/PencilKit/PKInkType) The type that defines the shape of stroked lines. [`extern PKInkType const PKInkTypeMarker;`](/documentation/PencilKit/PKInkTypeMarker) An inking tool that creates the appearance of a felt-tip marker. [`extern PKInkType const PKInkTypePen;`](/documentation/PencilKit/PKInkTypePen) An inking tool that creates the appearance of drawing with a pen. [`extern PKInkType const PKInkTypePencil;`](/documentation/PencilKit/PKInkTypePencil) An inking tool that creates the appearance of drawing with a pencil. [`extern PKInkType const PKInkTypeMonoline;`](/documentation/PencilKit/PKInkTypeMonoline) An inking tool that creates the appearance of a monoline pen. [`extern PKInkType const PKInkTypeFountainPen;`](/documentation/PencilKit/PKInkTypeFountainPen) An inking tool that creates the appearance of a calligraphy pen. [`extern PKInkType const PKInkTypeWatercolor;`](/documentation/PencilKit/PKInkTypeWatercolor) An inking tool that creates the appearance of a watercolor brush. [`extern PKInkType const PKInkTypeCrayon;`](/documentation/PencilKit/PKInkTypeCrayon) An inking tool that creates the appearance of a crayon. ### Working with colors [`class func convert(UIColor, from: UIUserInterfaceStyle, to: UIUserInterfaceStyle) -> UIColor`](/documentation/PencilKit/PKInkingToolReference/convert(_:from:to:)) Converts a color from one user interface style to another. ### Getting the standard ink widths [`class func defaultWidth(forInkType: __PKInkType) -> CGFloat`](/documentation/PencilKit/PKInkingToolReference/defaultWidth(forInkType:)) Returns the default line width for the specified tool type. [`class func minimumWidth(forInkType: __PKInkType) -> CGFloat`](/documentation/PencilKit/PKInkingToolReference/minimumWidth(forInkType:)) Returns the minimum allowed line width for the specified tool type. [`class func maximumWidth(forInkType: __PKInkType) -> CGFloat`](/documentation/PencilKit/PKInkingToolReference/maximumWidth(forInkType:)) Returns the maximum allowed line width for the specified tool type. ### Supporting backward compatibility [`var requiredContentVersion: PKContentVersion`](/documentation/PencilKit/PKInkingToolReference/requiredContentVersion) The version of PencilKit necessary to use the inking tool. ### Initializers [`init(inkType: __PKInkType, color: UIColor, width: CGFloat, azimuth: CGFloat)`](/documentation/PencilKit/PKInkingToolReference/init(inkType:color:width:azimuth:)) ### Instance Properties [`var azimuth: CGFloat`](/documentation/PencilKit/PKInkingToolReference/azimuth) The base angle of the ink. ### Type Methods [`class func invertColor(CGColor) -> Unmanaged`](/documentation/PencilKit/PKInkingToolReference/invertColor(_:)) Converts a color from light to dark appearance or vice versa. ## Relationships ### Conforms To [`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol) [`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible) [`Sendable`](/documentation/Swift/Sendable) [`CVarArg`](/documentation/Swift/CVarArg) [`NSCopying`](/documentation/Foundation/NSCopying) [`Equatable`](/documentation/Swift/Equatable) [`Hashable`](/documentation/Swift/Hashable) [`SendableMetatype`](/documentation/Swift/SendableMetatype) [`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible) --- Copyright © 2026 Apple Inc. 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