Small error with PHP Button/Menu Script - Working Code Included Too.

From: Shaun (smacpher_at_gmail.com)
Date: 01/18/05 

Date: 18 Jan 2005 12:33:23 -0800

Good day everyone :),

I am having some problems with a script to make buttons/menus from
here (http://www.jwweb.com/20020731.html) the text is released under
the "Gnu Public License for open-source material".

I will put ////// where the code breaks down:

--- Code for buttons ---

<?
// check we have the appropriate variable data
// variables are button-text and color

if (empty($button_text))
   $button_text = "Sample";
if (empty($color))
   $color = "blue"; if (empty($red))
   $red= 0;
if (empty($grn))
   $grn = 0;
if (empty($blu))
   $blu = 0;

// create an image of the right background and check size
$im = imagecreatefromgif ("$color-button.gif");

$width_image = ImageSX($im);
$height_image = ImageSY($im);

// Our images need a 10 pixel margin in from the edge image
$width_image_wo_margins = $width_image - (2 * 10);
$height_image_wo_margins = $height_image - (2 * 10);

// Work out if the font size will fit and make it smaller until it
does
// Start out with the biggest size that will reasonably fit on our
buttons
$font_size = 33;

do
{
   $font_size--;

   // find out the size of the text at that font size
   $bbox=imagettfbbox ($font_size, 0, $font_name, $button_text);

   $right_text = $bbox[2]; // right co-ordinate
   $left_text = $bbox[0]; // left co-ordinate
   $width_text = $right_text - $left_text; // how wide is it?
   $height_text = abs($bbox[7] - $bbox[1]); // how tall is it?
   

//////The code breaks down after the 8 in "8 &&"

} while ( $font_size>8 &&
               ( $height_text>$height_image_wo_margins ||
                  $width_text>$width_image_wo_margins )
            );

if ( $height_text>$height_image_wo_margins ||
       $width_text>$width_image_wo_margins )
{
   // no readable font size will fit on button
   echo "Text given will not fit on button.<BR>";
}

else
{
   // We have found a font size that will fit
   // Now work out where to put it

   $text_x = $width_image/2.0 - $width_text/2.0;
   $text_y = $height_image/2.0 - $height_text/2.0 ;

   if ($left_text < 0)
         $text_x += abs($left_text); // add factor for left
overhang

   $above_line_text = abs($bbox[7]); // how far above the baseline?
   $text_y += $above_line_text; // add baseline factor
   
   $text_y -= 2; // adjustment factor for shape of our template

   $white = ImageColorAllocate ($im, $red, $grn, $blu);

   ImageTTFText ($im, $font_size, 0, $text_x, $text_y, $white,
$font_name, $button_text);

   Header ("Content-type: image/gif");
   ImageGif ($im);
}

ImageDestroy ($im);
?> 

---
I cut away some of the non working code and it works well here:
--- Working code ---
<?
// check we have the appropriate variable data
// variables are button-text and color
if (empty($button_text))
   $button_text = "Sample";
if (empty($color))
   $color = "blue"; if (empty($red))
   $red= 0;
if (empty($grn))
   $grn = 0;
if (empty($blu))
   $blu = 0;
   
   // create an image of the right background and check size
$im = imagecreatefrompng("$color-button.png");
$width_image = ImageSX($im);
$height_image = ImageSY($im);
// Our images need a 10 pixel margin in from the edge image
$width_image_wo_margins = $width_image - (2 * 10);
$height_image_wo_margins = $height_image - (2 * 10);
// Work out if the font size will fit and make it smaller until it
does
// Start out with the biggest size that will reasonably fit on our
buttons
$font_size = 33;
do
{
   $font_size--;
   // find out the size of the text at that font size
   $bbox=imagettfbbox ($font_size, 0, $font_name, $button_text);
   $right_text = $bbox[2];    // right co-ordinate
   $left_text = $bbox[0];      // left co-ordinate
   $width_text = $right_text - $left_text;   // how wide is it?
   $height_text = abs($bbox[7] - $bbox[1]);   // how tall is it?
   
} while ( $font_size>8 &&
               ( $height_text>$height_image_wo_margins ||
                  $width_text>$width_image_wo_margins )
            );
            
            if ( $height_text>$height_image_wo_margins ||
       $width_text>$width_image_wo_margins )
{
   // no readable font size will fit on button
   echo "Text given will not fit on button.<BR>";
}
else
{
   // We have found a font size that will fit
   // Now work out where to put it
   $text_x = $width_image/2.0 - $width_text/2.0;
   $text_y = $height_image/2.0 - $height_text/2.0 ;
   if ($left_text < 0)
         $text_x += abs($left_text);      // add factor for left
overhang
   $above_line_text = abs($bbox[7]);    // how far above the baseline?
   $text_y += $above_line_text;            // add baseline factor
   
   $text_y -= 2;   // adjustment factor for shape of our template
   $white = ImageColorAllocate ($im, $red, $grn, $blu);
   ImageTTFText ($im, $font_size, 0, $text_x, $text_y, $white,
$font_name, $button_text);
   Header ("Content-type: image/gif");
   ImageGif ($im);
}
ImageDestroy ($im);
?>
---
I was wondering if someone could tell me why it breaks down after the
8, and what I could do to fix it.  It works as it is now but I'd
prefer the feature for auto adjusting font etc. :).
The website in the first paragraph explains most/all of what the code
is doing - it is a very great website.  I wish there was a little
download kit though so people could be working from the same code /
image set :) (you have to copy the code section by section).
Thanks for your help,
Shaun