Weird aliasing with PNG files(?)

BlitzMax Forums/BlitzMax Beginners Area/Weird aliasing with PNG files(?)

Bukky (Posted 2006) [#1]

Hey guys, I've been noticing that when I load up and display my PNG files in BlitzMax that I get some weird aliasing around the edges. Is this a common issue? Is there a workaround?

Who was John Galt? (Posted 2006) [#2]

No - works fine here. Can you an example?

JazzieB (Posted 2006) [#3]

By weird, do you mean normal? PNG files contain alpha data, which would be responsible for the aliasing you are probably seeing, as BlitzMax uses this data as it should - when SetBlend ALPHABLEND is being used. Some code, the image in question and what you mean by "weird" will help us clear this up for you.

Dreamora (Posted 2006) [#4]

Are you displaying the image in a lower res than it actually is or is the image not PowerOf2? In this case it could be caused by mipmapping (mipmap is a default flag that is always applied to loaded images as long as you don't set different defaultflags before loading anything)

Yan (Posted 2006) [#5]

When you say 'weird aliasing', do you perchance mean a ghostly white halo effect and do you use photoshop?

Sin of Nature (Posted 2006) [#6]

Thats just what I was going ask ErnieTheEnigmaticElk. Photoshops handling of aliasing is different from most paint packages for some odd reason. I've encountered this before.

Yan (Posted 2006) [#7]

Yeah, it's cos PS makes the transparent pixels white when you export a PNG. When any kind of filtering is applied, the transparent white pixels are averaged with the edge of the image to produce the white halo.

Bukky (Posted 2006) [#8]

Hey guys. Thanks for all of the replies. I apologize for not responding sooner, as I've had finals at the university. I'll check out the photoshop suggestions!