BitmapDataExtensionsBeginDrawConicCurve(IReadWriteBitmapData, Pen, PointF, PointF, PointF, Single, DrawingOptions, AsyncConfig) Method

public static IAsyncResult BeginDrawConicCurve(
	this IReadWriteBitmapData bitmapData,
	Pen pen,
	PointF p1,
	PointF p2,
	PointF p3,
	float weight,
	DrawingOptions? drawingOptions = null,
	AsyncConfig? asyncConfig = null
)

<ExtensionAttribute>
Public Shared Function BeginDrawConicCurve ( 
	bitmapData As IReadWriteBitmapData,
	pen As Pen,
	p1 As PointF,
	p2 As PointF,
	p3 As PointF,
	weight As Single,
	Optional drawingOptions As DrawingOptions = Nothing,
	Optional asyncConfig As AsyncConfig = Nothing
) As IAsyncResult

public:
[ExtensionAttribute]
static IAsyncResult^ BeginDrawConicCurve(
	IReadWriteBitmapData^ bitmapData, 
	Pen^ pen, 
	PointF p1, 
	PointF p2, 
	PointF p3, 
	float weight, 
	DrawingOptions^ drawingOptions = nullptr, 
	AsyncConfig^ asyncConfig = nullptr
)

[<ExtensionAttribute>]
static member BeginDrawConicCurve : 
        bitmapData : IReadWriteBitmapData * 
        pen : Pen * 
        p1 : PointF * 
        p2 : PointF * 
        p3 : PointF * 
        weight : float32 * 
        ?drawingOptions : DrawingOptions * 
        ?asyncConfig : AsyncConfig 
(* Defaults:
        let _drawingOptions = defaultArg drawingOptions null
        let _asyncConfig = defaultArg asyncConfig null
*)
-> IAsyncResult 

Parameters

bitmapData  IReadWriteBitmapData

The IReadWriteBitmapData instance to draw on.

pen  Pen

The Pen that determines the characteristics of the curves.

p1  PointF

The starting point of the conic curve.

p2  PointF

The control point of the conic curve.

p3  PointF

The ending point of the conic curve.

weight  Single

The weight of the conic curve, which determines the shape of the curve. Must be a positive value.

drawingOptions  DrawingOptions  (Optional)

A DrawingOptions instance that specifies the drawing options to use. If , then the default options are used. This parameter is optional.
Default value: .

asyncConfig  AsyncConfig  (Optional)

The configuration of the asynchronous operation such as parallelization, cancellation, reporting progress, etc. When Progress is set in this parameter, then this library always passes a DrawingOperation instance to the generic methods of the IAsyncProgress interface. This parameter is optional.
Default value: .

Return Value

Usage Note

If the weight is 1, the conic curve is equivalent to a parabolic (quadratic) Bézier curve. If the weight is less than 1, the curve is an elliptic arc, and if it's greater than 1, the curve is a hyperbolic arc.

This method tries to use a shortcut to draw the curve directly, which is faster than creating a Path and adding the curve to it. A shortcut is possible when the specified pen has a width between 0.25 and 1, it uses a solid Brush with an opaque color, and if drawingOptions is either , or its FastThinLines is enabled in drawingOptions, it specifies that no anti-aliasing and no alpha blending is required, the transformation is the identity matrix, and neither Quantizer nor Ditherer is specified.

When no shortcut can be used and the same curve is drawn repeatedly, creating a Path with PreferCaching enabled can provide a better performance.

In .NET Framework 4.0 and above you can use also the DrawConicCurveAsync methods.

To finish the operation and to get the exception that occurred during the operation you have to call the EndDrawConicCurve method.

This method is not a blocking call even if the MaxDegreeOfParallelism property of the asyncConfig parameter is 1.

If the curve is drawn by using a shortcut, then the operation is executed synchronously, it cannot be canceled, it is not parallelized, and there is no progress reporting, regardless of the asyncConfig parameter.

Reference