PolyDraw

The PolyDraw function draws a set of line segments and Bézier curves.

BOOL PolyDraw(
  HDC hdc,               // handle to a device context
  CONST POINT *lppt,     // pointer to array of points
  CONST BYTE *lpbTypes,  // pointer to line and curve identifiers
  int cCount             // count of points
);
 

Parameters

hdc
Handle to a device context.
lppt
Pointer to an array of POINT structures that contains the endpoints for each line segment and the endpoints and control points for each Bézier curve.
lpbTypes
Pointer to an array that specifies how each point in the lppt array is used. Types can be one of the following:
Type Meaning
PT_MOVETO Specifies that this point starts a disjoint figure. This point becomes the new current position.
PT_LINETO Specifies that a line is to be drawn from the current position to this point, which then becomes the new current position.
PT_BEZIERTO Specifies that this point is a control point or ending point for a Bézier curve.
PT_BEZIERTO types always occur in sets of three. The current position defines the starting point for the Bézier curve. The first two PT_BEZIERTO points are the control points, and the third PT_BEZIERTO point is the ending point. The ending point becomes the new current position. If there are not three consecutive PT_BEZIERTO points, an error results.

A PT_LINETO or PT_BEZIERTO type can be combined with the following value by using the bitwise operator OR to indicate that the corresponding point is the last point in a figure and the figure is closed:
Value Meaning
PT_CLOSEFIGURE Specifies that the figure is automatically closed after the PT_LINETO or PT_BEZIERTO type for this point is done. A line is drawn from this point to the most recent PT_MOVETO or MoveToEx point.
This value is combined with the PT_LINETO type for a line, or with the PT_BEZIERTO type of the ending point for a Bézier curve, by using the bitwise operator OR.
The current position is set to the ending point of the closing line.

cCount
Specifies the total number of points in the lppt array, the same as the number of bytes in the lpbTypes array.

Return Values

If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero.

Windows NT: To get extended error information, call GetLastError.

Remarks

The PolyDraw function can be used in place of consecutive calls to MoveToEx, LineTo, and PolyBezierTo functions to draw disjoint figures. The lines and curves are drawn using the current pen and figures are not filled. If there is an active path started by calling BeginPath, PolyDraw adds to the path.

The points contained in the lppt array and in the lpbTypes array indicate whether each point is part of a MoveTo, LineTo, or PolyBezierTo operation. It is also possible to close figures.

This function updates the current position.

QuickInfo

  Windows NT: Requires version 3.1 or later.
  Windows: Unsupported.
  Windows CE: Unsupported.
  Header: Declared in wingdi.h.
  Import Library: Use gdi32.lib.

See Also

Lines and Curves Overview, Line and Curve Functions, BeginPath, EndPath, LineTo, MoveToEx, POINT, PolyBezierTo, PolyLine