Joined: July 2004
||Posted: July 06 2007,14:20
What do you mean there aren't enough pixels? Smooth diagonal lines can be faked even in a 16x16 image.
Your problem with Newtux is not just jagged lines, but the fact that there are purple pixels mixed in making the lines appear even more jagged. Zoom in and you'll see them very clearly. It is as if the image was originally on a purple or pink background which was incompletely removed to make transparent.
This is a gif image, which implies no antialiasing from foreground to background. Antialiasing can be faked if you know for sure what the background of the image is going to be, but in this case I would say purple is probably not the color to use. Personally I would completely avoid the antialiasing fake and try to make the edges solid color against solid (or transparent) color. The purple should never have existed in the first place, though, as far as I can guess. There is a postscript version of Tux available which can be used at any resolution, and will not have strange artifacts like this.
The gradient in the "4" seems to enhance the appearance of the jagged edges. In low-color, low-resolution images it is impossible to create a gradient that moves seamlessly from one color to the next. These seams, or waves, are exaggerated when they are crossed with an area of solid color (or no color). It is my belief that if the 4 was a solid color it would have much cleaner edges just by that change.
That triangle I mentioned earlier is a pretty huge design flaw. It's a distraction, an unbalanced focal point, and can even be viewed as an artifact (is it a horn, an ear, just a mistake?). If it were me, I probably would have chosen a different font, or at least filled the triangle or nudged Tux a few pixels.
As far as Sunset goes, I was going to go on about complex gradients in low-color images, but on closer look the gradients themselves are surprisingly well-preserved (at first it looked like the water was heavily pixilated, but i think it's just shadows on the water). The text, however, looks mottled and eaten away in places. It may have been caused by using a too-thin font, or an anti-aliased or badly anti-aliased font. If a particular font does not have clean edges at a desired resolution, it's often a good idea to try a different font.