in reply to font measurement

You need to obtain a TK::Font object for the font you wish to use, then call the measure( $text ) method:

#! perl -slw
use strict;
use Tk;
use Tk::Font;

my $mw = MainWindow->new();

for my $name ( 'system' ) { #$mw->fontNames
    print "Using font $name";
    my $font = $mw->fontCreate( $name );

    for my $text (
        'The quick brown fox jumps over the lazy dog',
        'THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG'
    ) {
        printf "$text measures %d pixels\n", $font->measure( $text );
    }
}
__END__
C:\test>junk44
Using font system
The quick brown fox jumps over the lazy dog measures 302 pixels
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG measures 409 pixels

[download]

See the Tk::Font POD for (a little) more info, then google for more.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

The start of some sanity?

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Re^2: font measurement
by preahkumpii (Novice) on Jan 31, 2012 at 03:12 UTC
    Thank you for your help. Pardon the ignorance, but I have 3 questions:
    1. I don't understand this comment. Why is it there? #$mw->fontNames
    2. What is the use of the %d variable?
    3. Why was the command $font->measure( $text ) placed after the print command?
    UPDATE: I must be missing something. I thought I would put the name of the font of my choice from my system in place of the 'system' in your code. No matter what font I put there, even a very wide one like Trajan Pro, I get the same pixel width.
[reply]

      Sorry. That's what I assumed also. If it doesn't work, then you'll need to look for more or better documentation than this.

      1. The comment was left there to show my failed attempt to find a list of available fonts.
      2. %d isn't a variable, See the documentation for printf.
      3. See the documentation for printf
      With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.

      The start of some sanity?
[reply]
        Got it figured out. Here is the code: 
        #!/user/bin/perl
use warnings;
use strict;

use Tk;
use Tk::Font;

my $mw = MainWindow->new();   # window instance
$mw->fontCreate('josh', -family=>'Arial', -size=>20);   # give the fon
+t instance an arbitrary name 'josh'; specify font family and size her
+e

my $sentence = "This is my sample sentence to measure.";

my $length = $mw->fontMeasure('josh', $sentence);     # use the arbitr
+ary font name here with the text to measure

print "Your sample sentence is $length pixels long in the specified fo
+nt and size.\n";

        [download]

        Basically, there are several keys. First, you assign the window instance to a variable. Then, you use that variable to create the instance of the font. You give the font an arbitrary name. The way you pick your font face is by giving a value to the 'family' option. This is better than specifying a ttf file or likewise (which you can't do anyhow) b/c you can also specify the font weight, etc., within that family (Arial bold, italic, etc.). You set the size and the font is ready to go. So to use the fontMeasure procedure, you simply refer to the font instance as you named it and give it a string. It returns the measurement in pixels.

        Thanks for all the help.

[reply]
[d/l]

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