This topic has not yet been rated - Rate this topic

CDC::GetPath

Visual Studio 2012

Retrieves the coordinates defining the endpoints of lines and the control points of curves found in the path that is selected into the device context.

int GetPath( 
   LPPOINT lpPoints, 
   LPBYTE lpTypes, 
   int nCount  
) const;

Parameters

lpPoints

Points to an array of POINT data structures or CPoint objects where the line endpoints and curve control points are placed.

lpTypes

Points to an array of bytes where the vertex types are placed. Values are one of the following:

PT_MOVETO Specifies that the corresponding point in lpPoints starts a disjoint figure.
PT_LINETO Specifies that the previous point and the corresponding point in lpPoints are the endpoints of a line.
PT_BEZIERTO Specifies that the corresponding point in lpPoints is a control point or ending point for a Bzier curve.

PT_BEZIERTO types always occur in sets of three. The point in the path immediately preceding them defines the starting point for the Bzier curve. The first two PT_BEZIERTO points are the control points, and the third PT_BEZIERTO point is the end point (if hard-coded).

A PT_LINETO or PT_BEZIERTO type may be combined with the following flag (by using the bitwise operator OR) to indicate that the corresponding point is the last point in a figure and that the figure should be closed:
PT_CLOSEFIGURE Specifies that the figure is automatically closed after the corresponding line or curve is drawn. The figure is closed by drawing a line from the line or curve endpoint to the point corresponding to the last PT_MOVETO.

nCount

Specifies the total number of POINT data structures that may be placed in the lpPoints array. This value must be the same as the number of bytes that may be placed in the lpTypes array.

Return Value

If the nCount parameter is nonzero, the number of points enumerated. If nCount is 0, the total number of points in the path (and GetPath writes nothing to the buffers). If nCount is nonzero and is less than the number of points in the path, the return value is -1.

Remarks

The device context must contain a closed path. The points of the path are returned in logical coordinates. Points are stored in the path in device coordinates, so GetPath changes the points from device coordinates to logical coordinates by using the inverse of the current transformation. The FlattenPath member function may be called before GetPath, to convert all curves in the path into line segments.

Example

See the example for CDC::BeginPath.

Requirements

Header: afxwin.h

Reference

CDC Class

Hierarchy Chart

CDC::FlattenPath

CDC::PolyDraw

CDC::WidenPath

Did you find this helpful? Yes No

Not accurate

Not enough depth

Need more code examples

(1500 characters remaining)