Tk_GetDash(3TK) Tk Library Procedures Tk_GetDash(3TK)__________________________________________________________________________________________________________________________________________________NAME
Tk_GetDash - convert from string to valid dash structure.
SYNOPSIS
#include <tk.h>
int
Tk_GetDash(interp, string, dashPtr)
ARGUMENTS
Tcl_Interp *interp(in)
Interpreter to use for error reporting.
CONST char * string(in)
Textual value to be converted.
Tk_Dash *dashPtr (out) Points to place to store the dash pattern value converted from string.
_________________________________________________________________DESCRIPTION
These procedure parses the string and fills in the result in the Tk_Dash structure. The string can be a list of integers or a character
string containing only [.,-_] or spaces. If all goes well, TCL_OK is returned. If string doesn't have the proper syntax then TCL_ERROR is
returned, an error message is left in the interpreter's result, and nothing is stored at *dashPtr.
The first possible syntax is a list of integers. Each element represents the number of pixels of a line segment. Only the odd segments are
drawn using the "outline" color. The other segments are drawn transparent.
The second possible syntax is a character list containing only 5 possible characters [.,-_ ]. The space can be used to enlarge the space
between other line elements, and can not occur as the first posibion in the string. Some examples:
-dash . = -dash {2 4}
-dash - = -dash {6 4}
-dash -. = -dash {6 4 2 4}
-dash -.. = -dash {6 4 2 4 2 4}
-dash {. } = -dash {2 8}
-dash , = -dash {4 4}
The main difference of this syntax with the previous is that it it shape-conserving. This means that all values in the dash list will be
multiplied by the line width before display. This assures that "." will always be displayed as a dot and "-" always as a dash regardless of
the line width.
On systems where only a limited set of dash patterns, the dash pattern will be displayed as the most close dash pattern that is available.
For example, on Windows only the first 4 of the above examples are available. The last 2 examples will be displayed identically as the
first one.
KEYWORDS
dash, conversion
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Availability | SUNWTk |
+--------------------+-----------------+
|Interface Stability | Uncommitted |
+--------------------+-----------------+
NOTES
Source for Tk is available on http://opensolaris.org.
Tk 8.3 Tk_GetDash(3TK)
Check Out this Related Man Page
XSetLineAttribute(3X11) MIT X11R4 XSetLineAttribute(3X11)Name
XSetLineAttribute, XSetDashes - GC convenience routines
Syntax
XSetLineAttributes(display, gc, line_width, line_style, cap_style, join_style)
Display *display;
GC gc;
unsigned int line_width;
int line_style;
int cap_style;
int join_style;
XSetDashes(display, gc, dash_offset, dash_list, n)
Display *display;
GC gc;
int dash_offset;
char dash_list[];
int n;
Arguments
cap_style Specifies the line-style and cap-style you want to set for the specified GC. You can pass or
dash_list Specifies the dash-list for the dashed line-style you want to set for the specified GC.
dash_offset
Specifies the phase of the pattern for the dashed line-style you want to set for the specified GC.
display Specifies the connection to the X server.
gc Specifies the GC.
join_style
Specifies the line join-style you want to set for the specified GC. You can pass or
line_style
Specifies the line-style you want to set for the specified GC. You can pass or
line_width
Specifies the line-width you want to set for the specified GC.
n Specifies the number of elements in dash_list.
Description
The function sets the line drawing components in the specified GC.
can generate and errors.
The function sets the dash-offset and dash-list attributes for dashed line styles in the specified GC. There must be at least one element
in the specified dash_list, or a error results. The initial and alternating elements (second, fourth, and so on) of the dash_list are the
even dashes, and the others are the odd dashes. Each element specifies a dash length in pixels. All of the elements must be nonzero, or a
error results. Specifying an odd-length list is equivalent to specifying the same list concatenated with itself to produce an even-length
list.
The dash-offset defines the phase of the pattern, specifying how many pixels into the dash-list the pattern should actually begin in any
single graphics request. Dashing is continuous through path elements combined with a join-style but is reset to the dash-offset between
each sequence of joined lines.
The unit of measure for dashes is the same for the ordinary coordinate system. Ideally, a dash length is measured along the slope of the
line, but implementations are only required to match this ideal for horizontal and vertical lines. Failing the ideal semantics, it is sug-
gested that the length be measured along the major axis of the line. The major axis is defined as the x axis for lines drawn at an angle
of between -45 and +45 degrees or between 315 and 225 degrees from the x axis. For all other lines, the major axis is the y axis.
can generate and errors.
Diagnostics
The server failed to allocate the requested resource or server memory.
A value for a GContext argument does not name a defined GContext.
Some numeric value falls outside the range of values accepted by the request.
Unless a specific range is specified for an argument, the full range defined by the argument's type is accepted. Any argument
defined as a set of alternatives can generate this error.
See AlsoXCreateGC(3X11), XQueryBestSize(3X11), XSetArcMode(3X11), XSetClipOrigin(3X11), XSetFillStyle(3X11), XSetFont(3X11), XSetState(3X11), XSet-
Tile(3X11)
X Window System: The Complete Reference, Second Edition, Robert W. Scheifler and James Gettys
XSetLineAttribute(3X11)