GraphicsPathIterator::NextSubpath(constGraphicsPath,BOOL) method (gdipluspath.h)

The GraphicsPathIterator::NextSubpath method gets the next figure (subpath) from this iterator's associated path.


INT NextSubpath(
  [out] const GraphicsPath *path,
  [out] BOOL               *isClosed


[out] path

Type: GraphicsPath*

Pointer to a GraphicsPath object. This method sets the data points of this GraphicsPath object to match the data points of the retrieved figure.

[out] isClosed

Type: BOOL*

Pointer to a BOOL that receives a value that indicates whether the retrieved figure is closed. If the figure is closed, the received value is TRUE; otherwise, the received value is FALSE.

Return value

Type: INT

This method returns the number of data points in the retrieved figure. If there are no more figures to retrieve, this method returns 0.


The first time you call the GraphicsPathIterator::NextSubpath method of an iterator, it gets the first figure (subpath) of that iterator's associated path. The second time, it gets the second figure, and so on. Each time you call GraphicsPathIterator::NextSubpath, it returns the number of data points in the retrieved figure. When there are no figures remaining, it returns 0.


The following example creates a GraphicsPath object and adds five figures (also called subpaths) to the path. The code passes the address of the GraphicsPath object to a GraphicsPathIterator constructor to create an iterator that is associated with the path. The code calls the iterator's GraphicsPathIterator::NextSubpath method twice to retrieve the second figure (subpath) from the path. Then the code calls the DrawPath method of a Graphics object to draw that individual subpath.

VOID NextSubpathExample(HDC hdc)
   Graphics graphics(hdc);

   // Create a graphics path with five figures (subpaths).
   GraphicsPath path;

   path.AddRectangle(Rect(20, 20, 60, 30));   // Subpath count is 1.

   path.AddLine(100, 20, 160, 50);            // Subpath count is 2.
   path.AddArc(180, 20, 60, 30, 0.0f, 180.0f);

   path.AddRectangle(Rect(260, 20, 60, 30));  // Subpath count is 3.

   path.AddLine(340, 20, 400, 50);            // Subpath count is 4.
   path.AddArc(340, 20, 60, 30, 0.0f, 180.0f);
   path.AddRectangle(Rect(420, 20, 60, 30));  // Subpath count is 5.
   // Create an iterator, and associate it with the path.
   GraphicsPathIterator iterator(&path);

   // Get the second subpath by calling NextSubpath twice.
   GraphicsPath subpath;
   BOOL isClosed;
   INT count;
   count = iterator.NextSubpath(&subpath, &isClosed);
   count = iterator.NextSubpath(&subpath, &isClosed);

   // The variable "count" now holds the number of 
   // data points in the second subpath.

   // Draw the retrieved subpath.
   Pen bluePen(Color(255, 0, 0, 255));
   graphics.DrawPath(&bluePen, &subpath);


Minimum supported client Windows XP, Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header gdipluspath.h (include Gdiplus.h)
Library Gdiplus.lib
DLL Gdiplus.dll

See also

Constructing and Drawing Paths





GraphicsPathIterator::NextMarker Methods