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.Dd December 21, 2022
.Dt VG_LINE 3
.Os Agar 1.7
.Sh NAME
.Nm VG_Line
.Nd agar-vg line entity
.Sh SYNOPSIS
.Bd -literal
#include <agar/core.h>
#include <agar/gui.h>
#include <agar/vg.h>
.Ed
.Sh DESCRIPTION
.\" IMAGE(/widgets/VG_Line.png, "A VG_Line")
.Nm
is a
.Xr VG 3
node class which describes a line segment in terms of two points.
.Sh INTERFACE
.nr nS 1
.Ft "VG_Line *"
.Fn VG_LineNew "VG_Node *parent" "VG_Point *p1" "VG_Point *p2"
.Pp
.Ft "void"
.Fn VG_LineThickness "VG_Line *vl" "Uint8 thickness"
.Pp
.Ft "void"
.Fn VG_LineStipple "VG_Line *vl" "Uint16 pattern"
.Pp
.Ft "void"
.Fn VG_LineEndpointStyle "VG_Line *vl" "enum vg_endpoint_style style" "..."
.Pp
.nr nS 0
The
.Fn VG_LineNew
function creates a new line segment entity attached to
.Fa parent .
The
.Fa p1
and
.Fa p2
arguments define the endpoints.
.Pp
.Fn VG_LineThickness
defines the thickness of the line in pixels (default = 1 pixel).
Note that the line thickness parameter does not influence proximity queries
used by "select" tools. it only affects rendering, so very thick lines should
be rendered as
.Xr VG_Polygon 3
instead.
.Pp
.Fn VG_LineStipple
defines a 16-bit, OpenGL-style stipple pattern (default is 0xffff).
The order in which bits are used is undefined and depends on order of
rendering.
.Pp
By default, thick lines are rendered using a square endpoint style.
.Fn VG_LineEndpointStyle
specifies the style of endpoints to use in rendering the line.
Acceptable values include:
.Bd -literal
.\" SYNTAX(c)
enum vg_line_endpoint {
	VG_LINE_SQUARE,		/* Square endpoint */
	VG_LINE_BEVELED,	/* Beveled endpoint */
	VG_LINE_ROUNDED,	/* Rounded endpoint (circular) */
	VG_LINE_MITERED		/* Mitered endpoint */
};
.Ed
.Pp
If
.Dv VG_LINE_MITERED
is used,
.Fn VG_LineEndpointStyle
expects a following
.Ft Uint8
argument describing the miter length in pixels.
.Sh SEE ALSO
.Xr VG 3 ,
.Xr VG_Point 3
.Sh HISTORY
The
.Nm
class first appeared in Agar 1.3.3.