dynamic image manipulation
| From: | Kdtc | Date: | Fri, 13 Oct 2000 11:12:30 +0000 |
| Subject: | dynamic image manipulation | ||
| Groups: | php.general | ||
| Request: | Send a blank email to php-general+get-19988@lists.php.net to get a copy of this message | ||
I have a similar file as button.php, but it creates an empty 800x500
image.
Now, I have two frames (top_frame, and bot_frame) on my main window.
The topframe's source is a PHP file and ditto with the bottom frame.
I'm using javascript(side question: can javascript also
dynamically manipulate/draw graphics?) to create a series of random
values
and then I want them to be plotted (in real time) to the empty image;
thus,
creating a graph. So far, my botframe.php is as follows:
<?
$x = getenv("QUERY_STRING");
parse_str($x);
header("Content-type: image/png");
$im = ImageCreate(800,500);
$black = ImageColorAllocate($im,0,0,0);
$white = ImageColorAllocate($im,255,255,255);
ImageLine($im,$x0,$y0,$x1,$y1,$black);
ImagePNG($im);
?>
The topframe.php is like this:
*excerpt from javascript*
<html>
<head>
<script language="javascript">
function drawpoint(){
var k,i,prev;
k = 0;
for (i=1;i < 800;i++){
prev = k;
k = Math.random(1,20);
i = i+1;
top.document.image.src =
"imagecr.php?x0="+(i-1)+"&y0="+prev+"&x1="+i+"&y1="+k;
}
}
</script>
</head>
<body onload=drawpoint()>
</body>
</html>
Then in the top.document.image... line, it will take the created image
and overlay it
with line plots(from (x0,y0) to (x1,y1)).
As it stands, it does nothing of the sort, in fact, it just gives me a
blank page.
Can someone please tell me what I'm doing wrong, or rather, how I should
go about in doing this?
Any help appreciated.