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Arc Items

Items of type arc appear on the display as arc-shaped regions. An arc is a section of an oval delimited by two angles (specified by the :start and :extent options) and displayed in one of several ways (specified by the :style option). Arcs are created with widget commands of the following form:

pathName :create arc x1 y1 x2 y2 ?option value option value ...?
The arguments x1, y1, x2, and y2 give the coordinates of two diagonally opposite corners of a rectangular region enclosing the oval that defines the arc. After the coordinates there may be any number of option-value pairs, each of which sets one of the configuration options for the item. These same option\-value pairs may be used in itemconfigure widget commands to change the item's configuration. The following options are supported for arcs:

:extent degrees
Specifies the size of the angular range occupied by the arc. The arc's range extends for degrees degrees counter-clockwise from the starting angle given by the :start option. Degrees may be negative.
:fill color
Fill the region of the arc with color. Color may have any of the forms accepted by Tk_GetColor. If color is an empty string (the default), then then the arc will not be filled.
:outline color
Color specifies a color to use for drawing the arc's outline; it may have any of the forms accepted by Tk_GetColor. This option defaults to black. If the arc's style is arc then this option is ignored (the section of perimeter is filled using the :fill option). If color is specified as an empty string then no outline is drawn for the arc.
:start degrees
Specifies the beginning of the angular range occupied by the arc. Degrees is given in units of degrees measured counter-clockwise from the 3-o'clock position; it may be either positive or negative.
:stipple bitmap
Indicates that the arc should be filled in a stipple pattern; bitmap specifies the stipple pattern to use, in any of the forms accepted by Tk_GetBitmap. If the :fill option hasn't been specified then this option has no effect. If bitmap is an empty string (the default), then filling is done in a solid fashion.
:style type
Specifies how to draw the arc. If type is pieslice (the default) then the arc's region is defined by a section of the oval's perimeter plus two line segments, one between the center of the oval and each end of the perimeter section. If type is chord then the arc's region is defined by a section of the oval's perimeter plus a single line segment connecting the two end points of the perimeter section. If type is arc then the arc's region consists of a section of the perimeter alone. In this last case there is no outline for the arc and the :outline option is ignored.
:tags tagList
Specifies a set of tags to apply to the item. TagList consists of a list of tag names, which replace any existing tags for the item. TagList may be an empty list.
:width outlineWidth
Specifies the width of the outline to be drawn around the arc's region, in any of the forms described in the COORDINATES section above. If the :outline option has been specified as an empty string then this option has no effect. Wide outlines will be drawn centered on the edges of the arc's region. This option defaults to 1.0.


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