Ubuntu Manpage: GD::Text::Align - Draw aligned strings

NAME

       GD::Text::Align - Draw aligned strings

SYNOPSIS

         use GD;
         use GD::Text::Align;

         my $gd = GD::Image->new(800,600);
         # allocate colours, do other things.

         my $align = GD::Text::Align->new($gd
           valign => 'top',
           halign => 'right',
         );
         $align->set_font('arial', 12);
         $align->set_text('some string');
         @bb = $align->bounding_box(200, 400, PI/3);
         # you can do things based on the bounding box here
         $align->draw(200, 400, PI/3);

DESCRIPTION

       GD::Text::Align provides an object that draws a string aligned to a coordinate at an
       angle.

       For builtin fonts only two angles are valid: 0 and PI/2. All other angles will be
       converted to one of these two.

METHODS

This class inherits everything from GD::Text. I will only discuss the methods and
attributes here that are not discussed there, or that have a different interface or
behaviour. Methods directly inherited include "set_text" and "set_font".

GD::Text::Align->new($gd_object, attrib => value, ...)
Create a new object. The first argument to new has to be a valid GD::Image object. The
other arguments will be passed on to the set method.

$align->set(attrib => value, ...)
Set an attribute. Valid attributes are the ones discussed in GD::Text and:

valign, halign
Vertical and horizontal alignment of the string. See also set_valign and set_halign.

colour, color
Synonyms. The colour to use to draw the string. This should be the index of the colour
in the GD::Image object's palette. The default value is the last colour in the GD
object's palette at the time of the creation of $align.

$align->get(attribute)
Get the value of an attribute. Valid attributes are all the attributes mentioned in
GD::Text, the attributes mentioned under the "set" method and

x, y and angle
The x and y coordinate and the angle to be used. You can only do this after a call to
the draw or bounding_box methods. Note that these coordinates are not necessarily the
same ones that were passed in. Instead, they are the coordinates from where the GD
methods will start drawing. I doubt that this is very useful to anyone.

Note that while you can set the colour with both 'color' and 'colour', you can only get it
as 'colour'. Sorry, but such is life in Australia.

$align->set_valign(value)
Set the vertical alignment of the string to one of 'top', 'center', 'base' or 'bottom'.
For builtin fonts the last two are the same. The value 'base' denotes the baseline of a
TrueType font. Returns true on success, false on failure.

$align->set_halign(value)
Set the horizontal alignment of the string to one of 'left', 'center', or 'right'.
Returns true on success, false on failure.

$align->set_align(valign, halign)
Set the vertical and horizontal alignment. Just here for convenience. See also
"set_valign" and "set_halign". Returns true on success, false on failure.

$align->draw(x, y, angle)
Draw the string at coordinates x, y at an angle angle in radians. The x and y coordinate
become the pivot around which the string rotates.

Note that for the builtin GD fonts the only two valid angles are 0 and PI/2.

Returns the bounding box of the drawn string (see "bounding_box()").

$align->bounding_box(x, y, angle)
Return the bounding box of the string to draw. This returns an eight-element list (exactly
like the GD::Image->stringTTF method):

(x1,y1) lower left corner
(x2,y2) lower right corner
(x3,y3) upper right corner
(x4,y4) upper left corner

Note that upper, lower, left and right are relative to the string, not to the canvas.

The bounding box can be used to make decisions about whether to move the string or change
the font size prior to actually drawing the string.

NOTES

       As with all Modules for Perl: Please stick to using the interface. If you try to fiddle
       too much with knowledge of the internals of this module, you may get burned. I may change
       them at any time.

       You can only use TrueType fonts with version of GD > 1.20, and then only if compiled with
       support for this. If you attempt to do it anyway, you will get errors.

       In the following, terms like 'top', 'upper', 'left' and the like are all relative to the
       string to be drawn, not to the canvas.

BUGS

       Any bugs inherited from GD::Text.

COPYRIGHT

       copyright 1999 Martien Verbruggen (mgjv@comdyn.com.au)