CGpGraphicsPath.Warpmethod

Applies a warp transformation to this path.

GraphicsmethodCGpPath.incdocumented

Syntax

FUNCTION Warp (BYVAL destPoints AS GpPointF PTR, BYVAL count AS INT_, BYVAL srcRect AS GpRectF PTR, BYVAL pMatrix AS CGpMatrix PTR = NULL, BYVAL nWarpMode AS WarpMode = WarpModePerspective, BYVAL flatness AS SINGLE = FlatnessDefault) AS GpStatus

Parameters

Name		Description
`destPoints`		Pointer to an array of points that, along with the srcRect parameter, defines the warp transformation.
`count`		Integer that specifies the number of points in the destPoints array. The value of this parameter must be 3 or 4.
`srcRect`		Reference to a rectangle that, along with the destPoints parameter, defines the warp transformation.
`pMatrix`		Optional. Pointer to a Matrix object that represents a transformation to be applied along with the warp. If this parameter is NULL, no transformation is applied. The default value is NULL.
`nWarpMode`		Optional. Element of the WarpMode enumeration that specifies the kind of warp to be applied. The default value is WarpModePerspective.
`flatness`		Optional. Real number that influences the number of line segments that are used to approximate the original path. Small values specify that many line segments are used, and large values specify that few line segments are used. The default value is FlatnessDefault, which is a constant defined in Gdiplusenums.bi.

Return value

If the function succeeds, it returns StatusOk, which is an element of the GpStatus enumeration.

If the function fails, it returns one of the other elements of the GpStatus enumeration.

Description

Applies a warp transformation to this path. The Warp method also flattens (converts to a sequence of straight lines) the path.

Example

' ======================================================================================== ' The following example creates a GraphicsPath object and adds a closed figure to the path. ' The code defines a warp transformation by specifying a source rectangle and an array of ' four destination points. The source rectangle and destination points are passed to the ' Warp method. The code draws the path twice: once before it has been warped and once after ' it has been warped. ' ======================================================================================== SUB Example_Warp (BYVAL hdc AS HDC)

' // Create a graphics object from the window device context DIM graphics AS CGpGraphics = hdc ' // Set the scale transform graphics.ScaleTransformForDpi

' // Create a path. DIM points(0 TO 7) AS GpPointF = {(20.0, 60.0), (30.0, 90.0), _

(15.0, 110.0), (15.0, 145.0), (55.0, 145.0), (55.0, 110.0), (40.0, 90.0), (50.0, 60.0)}

DIM path AS CGpGraphicsPath path.AddLines(@points(0), 8) path.CloseFigure

' // Draw the path before applying a warp transformation. DIM bluePen AS CGpPen = ARGB_RED graphics.DrawPath(@bluePen, @path)

' // Define a warp transformation, and warp the path. DIM srcRect AS GpRectF = (10.0, 50.0, 50.0, 100.0) DIM destPts(0 TO 3) AS GpPointF = {(220.0, 10.0), (280.0, 10.0), (100.0, 150.0), (400.0, 150.0)} path.Warp(@destPts(0), 4, @srcRect)

' // Draw the warped path. graphics.DrawPath(@bluePen, @path)

' // Draw the source rectangle and the destination polygon. DIM blackPen AS CGpPen = ARGB_BLACK graphics.DrawRectangle(@blackPen, @srcRect) graphics.DrawLine(@blackPen, @destPts(0), @destPts(1)) graphics.DrawLine(@blackPen, @destPts(0), @destPts(2)) graphics.DrawLine(@blackPen, @destPts(1), @destPts(3)) graphics.DrawLine(@blackPen, @destPts(2), @destPts(3))

END SUB ' ========================================================================================

Reference

Include file CGpPath.inc
Defined in AfxNova/CGpPath.inc:532
Documented in Graphics/GdiPlus Classes/CGpGraphics Classes.md
Topic: CGpGraphics Class