[SOLVED] optional function parameters..

[slpctrl]

What I want to do, is have height width and percent optional. I got the height and width, but I can't get percent to work. My workaround was to set the default value of percent to null, and check if it's not null if it's not, calculate the width and height using my formula but it won't work at all. Can anyone help

 

<?php

//begin function
function sizemark($image, $w = 320, $h = 240, $percent = NULL)
{
   header("Content-type: image/jpeg");
   if (!is_null($percent))
   {
    $w = imagesx($image) * $percent;
    $h = imagesy($image) * $percent;
   }
   $x = @getimagesize($image);
   $sw = $x[0];
   $sh = $x[1];
   $new = @ImageCreateFromJPEG($image) or
   $new = @ImageCreateFromPNG($image) or
   $new = @ImageCreateFromGIF($image) or
   $new = false;
   if(!$new)
   {
    readfile($new);
   }
   else
   {
   $thumb = @ImageCreateTrueColor($w, $h);
   @ImageCopyResampled($thumb, $new, 0, 0, 0, 0, $w, $h, $sw, $sh);
   $image = $thumb;
   $watermark = imagecreatefrompng('watermark.png');
   $watermark_width = imagesx($watermark);
   $watermark_height = imagesy($watermark);
   $dest_x = (imagesx($image) - $watermark_width)/2;
   $dest_y = (imagesy($image) - $watermark_height)/2;
   imagecopymerge($image, $watermark, $dest_x, $dest_y, 0, 0, $watermark_width,
   $watermark_height, 30);
   imagejpeg($image);
   imagedestroy($image);
   imagedestroy($watermark);
   return $image;
   }
   return false;
}
//end function

$image = $_GET['image'];
$w = $_GET['w'];
$h = $_GET['h'];
$percent = $_GET['percent'];

if(isset($image) && isset($w) && isset($h) && !empty($image)
&& !empty($w) && !empty($h))

sizemark($image, $width, $height);

elseif(isset($percent) && isset($image) && !empty($percent) && !empty($image)
&& empty($w) && empty($h))

sizemark($image, NULL, NULL, $percent);

elseif(isset($image) && empty($w) && empty($h) && empty($percent))

sizemark($image);

else
die();
?>

[slpctrl]

<?php
//begin function
function sizemark($image, $w = 320, $h = 240)
{
   header("Content-type: image/jpeg");
   $x = @getimagesize($image);
   $sw = $x[0];
   $sh = $x[1];
   $new = @ImageCreateFromJPEG($image) or
   $new = @ImageCreateFromPNG($image) or
   $new = @ImageCreateFromGIF($image) or
   $new = false;
   if(!$new)
   {
    readfile($new);
   }
   else
   {
   $thumb = @ImageCreateTrueColor($w, $h);
   @ImageCopyResampled($thumb, $new, 0, 0, 0, 0, $w, $h, $sw, $sh);
   $image = $thumb;
   $watermark = imagecreatefrompng('watermark.png');
   $watermark_width = imagesx($watermark);
   $watermark_height = imagesy($watermark);
   $dest_x = (imagesx($image) - $watermark_width)/2;
   $dest_y = (imagesy($image) - $watermark_height)/2;
   imagecopymerge($image, $watermark, $dest_x, $dest_y, 0, 0, $watermark_width,
   $watermark_height, 30);
   imagejpeg($image);
   imagedestroy($image);
   imagedestroy($watermark);
   return $image;
   }
   return false;
}
//end function

$image = $_GET['image'];
$w = $_GET['w'];
$h = $_GET['h'];

if(isset($image) && isset($w) && isset($h)
&& !empty($image) && !empty($w) && !empty($h))
sizemark($image,$w,$h);
elseif(isset($image) && empty($w) && empty($h))
sizemark($image);
else
die();
?>

 

How about this. This is my working script, how do I add an optional percent to scale option to it?

[ablueycolor]

I didnt take the time to verify this code works but it is a minor improvement to your original.  Please make note of the use of ternary operators at the bottom of the code:

 

<?php

//begin function
function sizemark($image, $w = 320, $h = 240, $percent = NULL) {
    header("Content-type: image/jpeg");

    if (!is_null($percent)) {
        $w = imagesx($image) * $percent;
        $h = imagesy($image) * $percent;
    } else {
        $x = @getimagesize($image);
        $w = $x[0];
        $h = $x[1];
    }

    $new = @ImageCreateFromJPEG($image) or
    $new = @ImageCreateFromPNG($image) or
    $new = @ImageCreateFromGIF($image) or
    $new = false;

    if(!$new) {
        readfile($new);
    } else {
       $thumb = @ImageCreateTrueColor($w, $h);
       @ImageCopyResampled($thumb, $new, 0, 0, 0, 0, $w, $h, $sw, $sh);
       $image = $thumb;
       $watermark = imagecreatefrompng('watermark.png');
       $watermark_width = imagesx($watermark);
       $watermark_height = imagesy($watermark);
       $dest_x = (imagesx($image) - $watermark_width)/2;
       $dest_y = (imagesy($image) - $watermark_height)/2;
       imagecopymerge($image, $watermark, $dest_x, $dest_y, 0, 0, $watermark_width, $watermark_height, 30);
       imagejpeg($image);
       imagedestroy($image);
       imagedestroy($watermark);
       return $image;
    }
    return false;
}
//end function

$image = $_GET['image'];
if (!empty($image['name'])) {
    $w = (!empty($_GET['w'])) ? $_GET['w'] : 320;
    $h = (!empty($_GET['h'])) ? $_GET['h'] : 240;
    $percent = (!empty($_GET['percent'])) ? $_GET['percent'] : NULL;

    sizemark($image, $width, $height);
} else die();
?>

[rarebit]

Well I was just going to swap it about a bit...

function sizemark($image, $w = 320, $h = 240, $percent = NULL)

to

function sizemark($image, $percent = NULL, $w = 320, $h = 240)

And call it in these two ways:

sizemark($img, NULL, 64, 128);
sizemark($img, 50);

 

Your issue was, that you were passing NULL instead of a number, and therefore changing the default value...

[ablueycolor]

Also, I didn't change the line:

 

@ImageCopyResampled($thumb, $new, 0, 0, 0, 0, $w, $h, $sw, $sh);

 

Which still uses the undefined variables $sh and $sw.  To continue using these variables, modify the following lines:

 

<?php
    if (!is_null($percent)) {
        $sw = imagesx($image);
        $sh = imagesy($image);
        $w = $sw * $percent;
        $h = $sh * $percent;
    } else {
        $x = @getimagesize($image);
        $w = $x[0];
        $h = $x[1];
    }
?>

[slpctrl]

Here's what my new code looks like, percent still doesn't work.

 

<?php



//begin function
function sizemark($image, $w = 320, $h = 240)
{
   header("Content-type: image/jpeg");
   $x = @getimagesize($image);
   $sw = $x[0];
   $sh = $x[1];
   $new = @ImageCreateFromJPEG($image) or
   $new = @ImageCreateFromPNG($image) or
   $new = @ImageCreateFromGIF($image) or
   $new = false;
   if(!$new)
   {
    readfile($new);
   }
   else
   {
   $thumb = @ImageCreateTrueColor($w, $h);
   @ImageCopyResampled($thumb, $new, 0, 0, 0, 0, $w, $h, $sw, $sh);
   $image = $thumb;
   $watermark = imagecreatefrompng('watermark.png');
   $watermark_width = imagesx($watermark);
   $watermark_height = imagesy($watermark);
   $dest_x = (imagesx($image) - $watermark_width)/2;
   $dest_y = (imagesy($image) - $watermark_height)/2;
   imagecopymerge($image, $watermark, $dest_x, $dest_y, 0, 0, $watermark_width,
   $watermark_height, 30);
   imagejpeg($image);
   imagedestroy($image);
   imagedestroy($watermark);
   return $image;
   }
   return false;
}
//end function


$image = $_GET['image'];
$w = $_GET['w'];
$h = $_GET['h'];
$p = $_GET['pct'];

if(isset($image) && isset($p))
{
   $a = imagesx($image);
   $b = imagesy($image);
   $nw = $a*$p;
   $nh = $b*$p;
   sizemark($image, $nw, $nh);
}
elseif(isset($image) && isset($w) && isset($h))
sizemark($image,$w,$h);
elseif(isset($image))
sizemark($image);
else
die();
?>

 

This time I decided to search for the GET variable P and if there, calculate the dimensions outside of the function. But I just can't do it :'(

[slpctrl]

Ah I figured it out after looking closer into some functions (thought they returned something that they didn't). Here's the workign code and sorry for the hassle

 

<?php

/*image resizer and watermarker written by slpctrl. to use, simply place on
server along with a watermark.png of your choice, and in the URL (resizer.php or
whatever), you simply append the image location, and optionally you may append
the width and height of the image. If nothing specified, it will make the
default value 320x240. You can use any of the following:

Specify a w and h in the URL as a GET variable
specify the percentage by which the image is decreased. 1=100%, .5=50% and so
forth
Specify none, and leave it at it's default values(320x240)
*/

//begin function
function sizemark($image, $w = 320, $h = 240)
{
   header("Content-type: image/jpeg");
   //retrieving the dimensions of image
   $x = @getimagesize($image);
   $sw = $x[0];
   $sh = $x[1];
   //setting the new drawn image as a $new variable based on it's file type
   $new = @ImageCreateFromJPEG($image) or
   $new = @ImageCreateFromPNG($image) or
   $new = @ImageCreateFromGIF($image) or
   $new = false;
   if(!$new)
   {
    readfile($new);
   }
   else
   {
   //Here are the GD library functions in use where we take the image, rescale,
   //get coordinates for watermark and all the other nice details and merge the 
   //watermark in the center of the scaled image and return the new image
   $thumb = @ImageCreateTrueColor($w, $h);
   @ImageCopyResampled($thumb, $new, 0, 0, 0, 0, $w, $h, $sw, $sh);
   $image = $thumb;
   $watermark = imagecreatefrompng('watermark.png');
   $watermark_width = imagesx($watermark);
   $watermark_height = imagesy($watermark);
   $dest_x = (imagesx($image) - $watermark_width)/2;
   $dest_y = (imagesy($image) - $watermark_height)/2;
   imagecopymerge($image, $watermark, $dest_x, $dest_y, 0, 0, $watermark_width,
   $watermark_height, 30);
   imagejpeg($image);
   imagedestroy($image);
   imagedestroy($watermark);
   return $image;
   }
   return false;
}
//end function

//variable setting
$image = $_GET['image'];
$w = $_GET['w'];
$h = $_GET['h'];
$p = $_GET['p'];

//check to see if image and percent are set and calculate the new dimensions
//based on the percentage given
if(isset($image) && isset($p))
{
   $x = @getimagesize($image);
   $sw = $x[0] * $p;
   $sh = $x[1] * $p;
   sizemark($image,$sw,$sh);
}
//check to see if image and dimensions of thumbnail are to be set
elseif(isset($image) && isset($w) && isset($h))
sizemark($image,$w,$h);
//check to see if only image is set, which will use default values
elseif(isset($image))
sizemark($image);
else
die();
?>