Polyline

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A polyline is a connected sequence of line or arc segments created as a single object. Use polylines if you want to edit all segments at once (although you can also edit them singly). You can apply various Fit types to polylines and close the polyline to form a polygon.
Closed polylines can be filled with solid color. LiteCAD treats such objects as polygons and the user can select them by clicking inside of their boundary(s).

To add polylines into a drawing use following functions:

Function	Meaning
lcBlockAddPolyline	Adds a polyline
lcBlockAddRPolygon	Adds regular polygon
lcPlineAddVer	Adds a polyline vertex
lcPlineAddVer2	Adds a polyline vertex with parameters
lcPlineAddVerDir	Adds a polyline vertex by direction from the previous vertex
lcPlineEnd	End of adding vertices
lcPlineFromPtbuf	Copies vertices from Points buffer object
lcPlineFromMpgon	Copies vertices from Multipolygon object
lcPlineFromFile	Copies vertices from a file

More polyline specific functions:

Function	Meaning
lcPlineDeleteVer	Deletes a vertex from a polyline
lcPlineDelExVers	Deletes extra vertices
lcPlineGetFirstVer lcPlineGetNextVer lcPlineGetLastVer lcPlineGetPrevVer	Used to sequentially retrieve all vertices from a polyline
lcPlineGetVer	Gets a polyline vertex by its index
lcPlineGetVerPt	Gets a polyline vertex by point
lcPlineGetSeg	Gets a polyline segment by point
lcPlineReverse	Reverse order of polyline vertices
lcPlineContainPoint	Determines if some point is placed inside of a polygon
lcPlineSetStartVer	Sets start vertex for closed polyline
lcPlineGetPoint	Gets a point on a polyline by distance from beginning
lcPlineGetDist	Gets a point on a polyline which is nearest to specified point
lcPlineDivide	Gets equidistant points on a polyline, by number of points
lcPlineDivide2	Gets equidistant points on a polyline, by a distance

A polyline has properties and functions derived from base class and the following specific properties:

Property	Type	Access	Meaning
LC_PROP_ENT_...    Base class properties
LC_PROP_PLINE_FIT	int	RW	Fit type
LC_PROP_PLINE_NVERS	int	R	Number of vertices
LC_PROP_PLINE_CLOSED	bool	RW	Closed polyline
LC_PROP_PLINE_WIDTH	float bool	RW	Constant width
LC_PROP_PLINE_RADIUS	float bool	RW	Constant radius (for rounded polyline)
LC_PROP_PLINE_CHAMFER	bool	RW	Chamfer or arc (for rounded polyline)
LC_PROP_PLINE_LEN	float	R	Length
LC_PROP_PLINE_AREA	float	R	Area
LC_PROP_PLINE_HASANG0	bool	RW	Has start angle (for LC_PLFIT_SPLINE)
LC_PROP_PLINE_ANG0	float	RW	Start angle (for LC_PLFIT_SPLINE)
LC_PROP_PLINE_HASANG2	bool	RW	Has end angle (for LC_PLFIT_SPLINE)
LC_PROP_PLINE_ANG2	float	RW	End angle (for LC_PLFIT_SPLINE)
LC_PROP_PLINE_CW	bool	R	"ClockWise direction" flag
LC_PROP_PLINE_CCW	bool	R	"Counter-ClockWise direction" flag

Polyline vertex properties (use vertex handle to access it):

Property	Type	Access	Meaning
LC_PROP_VER_X	float	RW	Coordinate X
LC_PROP_VER_Y	float	RW	Coordinate Y
LC_PROP_VER_Z	float	RW	Coordinate Z
LC_PROP_VER_FIX	bool	RW	"Fixed vertex" flag (for LC_PLFIT_LINQUAD).
LC_PROP_VER_RADIUS	float	RW	Radius of vertex arc (for LC_PLFIT_ROUND).
LC_PROP_VER_INDEX	int	R	Vertex index (from 0 to LC_PROP_PLINE_NVERS-1).
LC_PROP_VER_FIRST	bool	R	"First vertex" flag
LC_PROP_VER_LAST	bool	R	"Last vertex" flag
For the segment from current vertex to the next vertex
LC_PROP_VER_W0	float	RW	Start width
LC_PROP_VER_W1	float	RW	End width
LC_PROP_VER_SEGDX	float	RW	Delta X to the next vertex
LC_PROP_VER_SEGDY	float	RW	Delta Y to the next vertex
LC_PROP_VER_SEGANG	float	RW	Direction angle to the next vertex
LC_PROP_VER_SEGLEN	float	RW	Distance to the next vertex
For arc segment (LC_PLFIT_BULGE)
LC_PROP_VER_BULGE	float	RW	Bulge value
LC_PROP_VER_SEGARCANG	float	RW	Arc included Angle
LC_PROP_VER_SEGARCH	float	RW	Arc Height
LC_PROP_VER_SEGARCLEN	float	R	Arc Length
LC_PROP_VER_SEGARCRAD	float	R	Arc Radius

Grips

0...LC_PROP_PLINE_NVERS-1 - vertex position. The grip with additional square indicates current vertex (reflected in the properties window)

If you point cursor on a grip and click right button - context popup menu will appear:


See also

  Retrieve objects