a shortcut for basic dashed lines, making it easy to adjust the lengths:
<?php
$length1 = 20;
$length2 = 10;
$style = array_merge(array_fill(0, $length1, $red), array_fill(0, $length2, $w));
imagesetstyle($im, $style);
?>
imagesetstyle
(PHP 4 >= 4.0.6, PHP 5)
imagesetstyle — Set the style for line drawing
Description
imagesetstyle() sets the style to be used by all line drawing functions (such as imageline() and imagepolygon()) when drawing with the special color IMG_COLOR_STYLED or lines of images with color IMG_COLOR_STYLEDBRUSHED.
Parameters
- image
-
An image resource, returned by one of the image creation functions, such as imagecreatetruecolor().
- style
-
An array of pixel colors. You can use the IMG_COLOR_TRANSPARENT constant to add a transparent pixel.
Return Values
Returns TRUE on success or FALSE on failure.
Examples
Following example script draws a dashed line from upper left to lower right corner of the canvas:
Example #1 imagesetstyle() example
<?php
header("Content-type: image/jpeg");
$im = imagecreatetruecolor(100, 100);
$w = imagecolorallocate($im, 255, 255, 255);
$red = imagecolorallocate($im, 255, 0, 0);
/* Draw a dashed line, 5 red pixels, 5 white pixels */
$style = array($red, $red, $red, $red, $red, $w, $w, $w, $w, $w);
imagesetstyle($im, $style);
imageline($im, 0, 0, 100, 100, IMG_COLOR_STYLED);
/* Draw a line of happy faces using imagesetbrush() with imagesetstyle */
$style = array($w, $w, $w, $w, $w, $w, $w, $w, $w, $w, $w, $w, $red);
imagesetstyle($im, $style);
$brush = imagecreatefrompng("http://www.libpng.org/pub/png/images/smile.happy.png");
$w2 = imagecolorallocate($brush, 255, 255, 255);
imagecolortransparent($brush, $w2);
imagesetbrush($im, $brush);
imageline($im, 100, 0, 0, 100, IMG_COLOR_STYLEDBRUSHED);
imagejpeg($im);
imagedestroy($im);
?>
The above example will output something similar to:
Be aware that styles are applied towards the width of the line instead of linear.
To convert a style to be used for thick lines you can use the function below:
<?php
/*
ImageStyleThicken(<aStyle>,<iThickness>) --> <aThickStyle>
<aStyle> is the style array for a thickness of 1 (see imagesetstyle()).
<iThickness> is the new thickness to apply (see imagesetthickness()).
<aThickStyle> is the style array suitable for the given thickness.
*/
function ImageStyleThicken($_1,$_2) {
$a = array();
foreach ($_1 as $x) {
$i = $_2;
do $a[] = $x; while (--$i>0); }
return $a;
}
?>
Function to make a line with random fading:
<?php
function fading_line($img,$sx,$sy,$ex,$ey){
$r=rand(0,5);$g=rand(0,5);$b=rand(0,5);
$l=sqrt((($ex-$sx)*($ex-$sx))+(($ey-$sy)*($ey-$sy)));
for($i=0;$i<$l;$i++){
$a = array(255-((255/$l)*$i), 255,0,(255/$l)*$i/2,(255/$l)*$i,(255-((255/$l)*$i))/2);
$style[]=imagecolorallocate($img,$a[$r],$a[$g],$a[$b]);
}
imagesetstyle($img,$style);
imageline($img,$sx,$sy,$ex,$ey,IMG_COLOR_STYLED);
}
fading_line($img,10,20,490,40); // image, start x, start y, end x, end y
?>
Watch out! If you pass imagesetstyle() an empty array as the second argument, it will crash your server!
I was messing with it just earlier and accidentally did so, and the page took a good minute to process, when my Apache server came up with the good ol' Windows 'Send Error Report' window.
When lines drawn with imagesetstyle seem to produce a thin white line only, make sure antialiasing is disabled.
<?
imageantialias($im, false);
$style = array($gridxcolor, $gridxcolor, IMG_COLOR_TRANSPARENT, IMG_COLOR_TRANSPARENT);
imagesetstyle($im, $style);
imageline($im, $x, 0, $x, $ymax+5, IMG_COLOR_STYLED);
imageantialias($im, true);
?>
Setstyle and Antialias don't go together.
Use this to set the style to any combination of pixels.
You can pass as many modifiers as you wish.
Use the format [num]r[red]g[green]b[blue].
For example:
$im=dashed($im,"4r255g0b0","2r0g255b0","5r0g0b255");
imageline($im, 0, 0, 600, 600, IMG_COLOR_STYLED);
function dashed($im){
$size = func_num_args();
for($i = 0; $i < $size; $i++){
$arg = func_get_arg($i);
if(!is_resource($arg)){
$r=substr($arg,strpos($arg,"r")+1,
strpos($arg,"g")-strpos($arg,"r")-1);
$g=substr($arg,strpos($arg,"g")+1,
strpos($arg,"b")-strpos($arg,"g")-1);
$b=substr($arg,strpos($arg,"b")+1,
strlen($arg)-strpos($arg,"b"));
$color = imagecolorallocate($im,$r,$g,$b);
$x = substr($arg,0,strpos($arg,"r"));
$vals[$i] = array_fill(0,$x,$color);
}
}
for($k=0;$k<count($vals)+1;$k++)
if(array_key_exists($k,$vals)) $prop=array_merge($prop,$vals[$k]);
imagesetstyle($im, $prop);
return $im;
}
When drawing lines that are >1px thick you'll have to setup the array corresponding to this fact (since there's no multi-array support for this function).
For example if the line's 3 pixels thick each 2nd color goes to the 2nd line, each 3rd color to the 3rd line and so on.
