Prev Next

ExtCreatePen info  Overview  Group

The ExtCreatePen function creates a logical cosmetic or geometric pen that has the specified style, width, and brush attributes.

HPEN ExtCreatePen(

    DWORD dwPenStyle,

// pen style

    DWORD dwWidth,

// pen width

    CONST LOGBRUSH *lplb,

// pointer to structure for brush attributes

    DWORD dwStyleCount,

// length of array containing custom style bits

    CONST DWORD *lpStyle 

// optional array of custom style bits

   );

Parameters

dwPenStyle
Specifies a combination of type, style, end cap, and join attributes. The values from each category are combined by using the bitwise OR operator (|).

The pen type can be one of the following values:

Type

Description

PS_GEOMETRIC

Pen is geometric.

PS_COSMETIC

Pen is cosmetic.

The pen style can be any one of the following values:

Style

Description

PS_ALTERNATE

Windows NT: Pen sets every other pixel. (This style is applicable only for cosmetic pens.)

Windows 95: Not supported.

PS_SOLID

Pen is solid.

PS_DASH

Pen is dashed.

Windows 95: This style is not supported for geometric lines.

PS_DOT

Pen is dotted.

Windows 95: This style is not supported for geometric lines.

PS_DASHDOT

Pen has alternating dashes and dots.

Windows 95: This style is not supported for geometric lines.

PS_DASHDOTDOT

Pen has alternating dashes and double dots.

Windows 95: This style is not supported for geometric lines.

PS_NULL

Pen is invisible.

PS_USERSTYLE

Windows NT: Pen uses a styling array supplied by the user.

Windows 95: Not supported.

PS_INSIDEFRAME

Pen is solid. When this pen is used in any graphics device interface (GDI) drawing function that takes a bounding rectangle, the dimensions of the figure are shrunk so that it fits entirely in the bounding rectangle, taking into account the width of the pen. This applies only to geometric pens.

The end cap is only specified for geometric pens. The end cap can be one of the following values:

End cap

Description

PS_ENDCAP_ROUND

End caps are round.

PS_ENDCAP_SQUARE

End caps are square.

PS_ENDCAP_FLAT

End caps are flat.

The join is only specified for geometric pens. The join can be one of the following values:

Line join

Description

PS_JOIN_BEVEL

Joins are beveled.

PS_JOIN_MITER

Joins are mitered when they are within the current limit set by the SetMiterLimit function. If it exceeds this limit, the join is beveled.

PS_JOIN_ROUND

Joins are round.

Windows 95: The PS_ENDCAP_ROUND, PS_ENDCAP_SQUARE, PS_ENDCAP_FLAT, PS_JOIN_BEVEL, PS_JOIN_MITER, and PS_JOIN_ROUND styles are supported only for geometric pens when used to draw paths.

dwWidth
Specifies the width of the pen. If the dwPenStyle parameter is PS_GEOMETRIC, the width is given in logical units. If dwPenStyle is PS_COSMETIC, the width must be set to 1.
lplb
Points to a LOGBRUSH structure. If dwPenStyle is PS_COSMETIC, the lbColor member specifies the color of the pen and the lbStyle member must be set to BS_SOLID. If dwPenStyle is PS_GEOMETRIC, all members must be used to specify the brush attributes of the pen.
dwStyleCount
Specifies the length, in doubleword units, of the lpStyle array. This value must be zero if dwPenStyle is not PS_USERSTYLE.
lpStyle
Points to an array of doubleword values. The first value specifies the length of the first dash in a user-defined style, the second value specifies the length of the first space, and so on. This pointer must be NULL if dwPenStyle is not PS_USERSTYLE.

Return Values

If the function succeeds, the return value is a handle that identifies a logical pen.

If the function fails, the return value is zero. To get extended error information, call GetLastError.

Remarks

A geometric pen can have any width and can have any of the attributes of a brush, such as dithers and patterns. A cosmetic pen can only be a single pixel wide and must be a solid color, but cosmetic pens are generally faster than geometric pens.

The width of a geometric pen is always specified in world units. The width of a cosmetic pen is always 1.

End cap and join are only specified for geometric pens.

After an application creates a logical pen, it can select that pen into a device context by calling the SelectObject function. After a pen is selected into a device context, it can be used to draw lines and curves.

If dwPenStyle is PS_COSMETIC and PS_USERSTYLE, the entries in the lpStyle array specify lengths of dashes and spaces in style units. A style unit is defined by the device where the pen is used to draw a line.

If dwPenStyle is PS_GEOMETRIC and PS_USERSTYLE, the entries in the lpStyle array specify lengths of dashes and spaces in logical units.

If dwPenStyle is PS_ALTERNATE, the style unit is ignored and every other pixel is set.

If the lbStyle member of the LOGBRUSH structure pointed to by lplb is BS_PATTERN, the bitmap pointed to by the lbHatch member of that structure cannot be a dib section. A dib section is a bitmap created by CreateDibSection. If that bitmap is a dib section, the ExtCreatePen function fails.

When an application no longer requires a specified pen, it should call the DeleteObject function to delete the pen.

See Also

CreatePen, CreateDibSection, CreatePenIndirect, DeleteObject, GetObject, LOGBRUSH, SelectObject, SetMiterLimit