Windows PowerShell command on Get-command Tk

Manual Pages for UNIX Operating System command usage for man Tk_MeasureChars

Tk Library Procedures Tk_MeasureChars(3TK)

_________________________________________________________________

NAME

Tk_MeasureChars, Tk_TextWidth, Tk_DrawChars,

Tk_UnderlineChars - routines to measure and display simple

single-line strings.

SYNOPSIS

#include

int

Tk_MeasureChars(tkfont, string, numBytes, maxPixels, flags, lengthPtr)

int

Tk_TextWidth(tkfont, string, numBytes)

void

Tk_DrawChars(display, drawable, gc, tkfont, string, numBytes, x, y)

void

Tk_UnderlineChars(display, drawable, gc, tkfont, string, x, y, firstByte, lastByte)

ARGUMENTS

Tk_Font tkfont (in) Token for font in which

text is to be drawn or measured. Must have been returned by a previous

call to Tk_GetFont.

const char *string (in) Text to be measured or displayed. Need not be null terminated. Any

non-printing meta-

characters in the string (such as tabs, newlines,

and other control charac-

ters) will be measured or

displayed in a platform-

dependent manner. | int numBytes (in) || The maximum number of | bytes to consider when | measuring or drawing | string. Must be greater | than or equal to 0. int maxPixels (in) If maxPixels is >= 0, it specifies the longest permissible line length in pixels. Characters Tk Last change: 8.1 1

Tk Library Procedures Tk_MeasureChars(3TK)

from string are processed

only until this many pix-

els have been covered. If maxPixels is < 0, then the line length is unbounded and the flags argument is ignored.

int flags (in) Various flag bits OR-ed

together: TK_PARTIAL_OK

means include a character as long as any part of it fits in the length given by maxPixels; otherwise,

a character must fit com-

pletely to be considered.

TK_WHOLE_WORDS means stop

on a word boundary, if possible. If

TK_AT_LEAST_ONE is set,

it means return at least one character even if no characters could fit in

the length given by max-

Pixels. If

TK_AT_LEAST_ONE is set

and TK_WHOLE_WORDS is

also set, it means that if not even one word fits on the line, return the first few letters of the word that did fit; if not even one letter of the word fit, then the first letter will still be returned. int *lengthPtr (out) Filled with the number of pixels occupied by the number of characters returned as the result of

Tk_MeasureChars.

Display *display (in) Display on which to draw. Drawable drawable (in) Window or pixmap in which to draw. GC gc (in) Graphics context for drawing characters. The font selected into this GC must be the same as Tk Last change: 8.1 2

Tk Library Procedures Tk_MeasureChars(3TK)

the tkfont. int x, y (in) Coordinates at which to place the left edge of the baseline when displaying string. | int firstByte (in) || The index of the first |

byte of the first charac- |

ter to underline in the | string. Underlining | begins at the left edge | of this character. | int lastByte (in) || The index of the first |

byte of the last charac- |

ter up to which the | underline will be drawn. | The character specified | by lastByte will not | itself be underlined.

_________________________________________________________________

DESCRIPTION

These routines are for measuring and displaying simple

single-font, single-line, strings. To measure and display

single-font, multi-line, justified text, refer to the docu-

mentation for Tk_ComputeTextLayout. There is no programming

interface in the core of Tk that supports multi-font,

multi-line text; support for that behavior must be built on

top of simpler layers. Note that the interfaces described |

here are byte-oriented not character-oriented, so index |

values coming from Tcl scripts need to be converted to byte |

offsets using the Tcl_UtfAtIndex and related routines.

A glyph is the displayable picture of a letter, number, or some other symbol. Not all character codes in a given font have a glyph. Characters such as tabs, newlines/returns, and control characters that have no glyph are measured and

displayed by these procedures in a platform-dependent

manner; under X, they are replaced with backslashed escape sequences, while under Windows and Macintosh hollow or solid boxes may be substituted. Refer to the documentation for

Tk_ComputeTextLayout for a programming interface that sup-

ports the platform-independent expansion of tab characters

into columns and newlines/returns into multi-line text.

Tk_MeasureChars is used both to compute the length of a

given string and to compute how many characters from a Tk Last change: 8.1 3

Tk Library Procedures Tk_MeasureChars(3TK)

string fit in a given amount of space. The return value is

the number of bytes from string that fit in the space speci-

fied by maxPixels subject to the conditions described by

flags. If all characters fit, the return value will be num-

Bytes. *lengthPtr is filled with the computed width, in pixels, of the portion of the string that was measured. For example, if the return value is 5, then *lengthPtr is filled with the distance between the left edge of string[0] and the right edge of string[4].

Tk_TextWidth is a wrapper function that provides a simpler

interface to the Tk_MeasureChars function. The return value

is how much space in pixels the given string needs.

Tk_DrawChars draws the string at the given location in the

given drawable.

Tk_UnderlineChars underlines the given range of characters

in the given string. It doesn't draw the characters (which are assumed to have been displayed previously by

Tk_DrawChars); it just draws the underline. This procedure

is used to underline a few characters without having to con-

struct an underlined font. To produce natively underlined text, the appropriate underlined font should be constructed and used. KEYWORDS font

ATTRIBUTES

See attributes(5) for descriptions of the following attri-

butes:

_______________________________________

| ATTRIBUTE TYPE | ATTRIBUTE VALUE|

|____________________|__________________|_

| Availability | runtime/tk-8 |

|____________________|__________________|_

| Interface Stability| Uncommitted |

|____________________|_________________|

NOTES Source for Tk is available on http://opensolaris.org. Tk Last change: 8.1 4