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View Full Version : How to get 'clean' gifs on all backgrounds?


Borgs8472
09-09-2005, 09:12 PM
Oooh, a new forum!

Anyhow, I have to use two versions of my logo;

http://www.wordforge.net/forum/images/misc/translogo.gif

and

http://www.wordforge.net/forum/images/misc/translogo1.gif

The first for the light, the second for the dark skins.

Can you fade to transparent on the edges with gifs? Or is there a decent way of getting just one clean logo image? :/

Wayne Luke
09-12-2005, 06:23 PM
You can't with the GIF format. GIF only allows for one transparent color. When you anti-alias or smooth your images, this one transparent color needs to be the same as your intended background for the best effect. On any other background it will create a jagged look.

The PNG file format was created to get around this issue. It supports an alpha transparency layer which allows you to apply tranparency to one or more images. It was also created to reduce developers reliance on the GIF patent from Unisys. The problem with it and why it hasn't been adopted widely yet is Internet Explorer doesn't filter the alpha transparency by default. You have to apply a DirectX filter to the image so it appears correctly. Bad implementation by Microsoft Developers as this should be applied transparently but it is what we have. To show alpha transparency in IE, you need to apply modifications to vBulletin, but once applied they work great. The best is the one released for 3.5, though it should work on all versions since it doesn't rely on any vBulletin code.

You can find it here:
https://vborg.vbsupport.ru/showthread.php?t=94416

The only issue with the modification is that user's on slow connections may see a flicker in the images as the page loads as the filter isn't applied until the page finishes loading.

Borgs8472
09-15-2005, 12:18 AM
^ ^
ah, the reason I will never use png, revealed...

Alas, a couple of my users have trouble with javascript (e.g. in my java chat room, use of a java RSS feed), so I won't risk that in the logo, since it'd cause global problems which they can't avoid.

In the mean time I'll stick with different logos in the header, thanks for your help!

Wayne Luke
09-15-2005, 10:27 PM
Javascript != Java by the way... They are two completely different languages which share a name through a stupid marketing stunt by Netscape. A new official name of ECMAScript was adopted a few years ago. But it never caught on.

Borgs8472
09-15-2005, 10:35 PM
Hmm... good point.

I should experiment with the javascript png script elsewhere, get some feedback then consider it for use in the logo...