MapServer 5, AGG Antialiasing...
Steve.Lime at DNR.STATE.MN.US
Wed Sep 19 15:04:04 EDT 2007
Andreas is correct, with AGG it's anti-aliasing all the time. Our implementation uses GD as the
canvas for AGG to render into so rendering different layers with different drivers is not that
far fetched, but is not available currently.
Keep in mind that I think we will see some performance improvements. Thomas tried one right
before the 5.0 release with good success. It was just too late in the development cycle to commit
those changes without testing. If we can achieve approximately equal performance then I think
letting GD do what it's good at makes sense. That may mean allowing 24-bit output but losing
AA support for GD (which pales in comparison to AGG). Time will tell.
>>> On 9/18/2007 at 10:10 AM, in message <46EFEA7F.3040605 at territoriumonline.com>,
Andreas Albarello <andreas.albarello at TERRITORIUMONLINE.COM> wrote:
> Timothy J Nolte wrote:
>> Any way to selectively turn off the antialiasing
>> for a layer when using AGG? Thanks.
> Not that I'm aware of. It's my understanding that AGG works only that
> way, i.e. subpixel-rendering = always antialiased.
> I can see however how being able to individually select some layers to
> be drawn the old way (GD) would be a nice addition. I guess that's
> asking too much, though.
> Anyhow, I'm not so sure that simply getting rid of GD's RGB rendering in
> a future relase as suggested in the migration guide is a good idea,
> seeing that some users, especially those facing performance issues,
> might want to keep drawing non-antialiased maps.
> Best regards,
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