Christof,
Thanks for that, but I was really looking to see if there was a
browser-independent mechanism, essentially something like the Web archives
that IE has supported for years. I think adding components for this would be
over-complicating the matter.
Thanks anyway.
--rob
On 7/25/07, Christof Donat <[EMAIL PROTECTED]> wrote:
Am Mittwoch, 25. Juli 2007 schrieb Rob Desbois:
> Yes, sorry I didn't phrase my post very well: there is a URL for the
image,
> of course, but I was trying to emphasise that there isn't a URL to an
image
> cached on the server's filesystem to pass back, as I don't want to
> *permanently* cache the image (or implement a cleverer algorithm -
there's
> no need).
> I simply want the cached image (or intermediates) to be temporary; the
> user's session seems the obvious candidate for this type of storage to
me.
var ctx = $('canvas')[0].getContext("2d");
var img = new Image();
img.onload = function() {
ctx.drawImage(img,0,0);
ctx.beginPath();
ctx.moveTo(30,96);
ctx.lineTo(70,66);
ctx.lineTo(103,76);
ctx.lineTo(170,15);
ctx.stroke();
// ...
}
img.src = "/basicImage.png";
I am pretty shure that this is what you are looking for. I have the code
almost exactly from the first example of
http://developer.mozilla.org/en/docs/Canvas_tutorial:Using_images
The example should work in Firefox, Safari and Opera. For IE there is
IECanvas
(http://sourceforge.net/projects/iecanvas).
If you really need to care about Konqueror, you can try to mimic the
behaviour
you need with data URLs. For a refference how this could look like, see
PNGlets: http://www.elf.org/pnglets/
There is no really usefull Drawing solution on all Browsers. Changing data
URLs lie PNGlet is slow and annoying and IECanvas is slow and can not
handle
many drawing primitives - it gets slower all the time.
There was the possibility in IE 6 to use javascript URLs for images that
return monochrome XBM images which could have been colored and combined
with
filters. Alas MS doesn't support XBM any more, so there is not evan a
pita-way left.
Christof
--
Rob Desbois
Eml: [EMAIL PROTECTED]
Tel: 01452 760631
Mob: 07946 705987
"There's a whale there's a whale there's a whale fish" he cried, and the
whale was in full view.
...Then ooh welcome. Ahhh. Ooh mug welcome.
