hard to come up with a suitable topic name..
I'll just get into it, in my Twinsen game Im considering having the background's sky be spherical in real time, so when you jump up and down, move to the left/right you see the clouds and sky get warped on the sphere.
obviously, for Twinsen's current sky background:
when the engine warps it to a sphere, its made jagged, pixelated and the 1 pixel lines will be invisible at some points
the solution is to 2x the sky, and apply AA like so:
then, when you put it in the game, have the code shrink it to 50% so it looks exactly the same as the original.
except that when you warp it, it automatically AA's itself, because even though you don't see the 50% shades, they're just in between the displayed pixels, so when you shrink a certain part another 50% it goes to select the pixels halfway between the pixels displayed
kinda a mess to explain
here is the before and after, the before showcasing how it would look to just skew the original, un-aa'd sky:
jagged, and clearly not AA'd
and the after, showcasing how it looks when you skew the larger version with the AA:
smooth, and aa'd
just keep in mind this would be a much better example if I could spherize these without photoshop blurring them, and if you could see it move around in real time.
Just think back to old mode7 racers:
How if you lined up perfectly adjacent with the pixels of the track image, lines parallel to the horizon would flash and flicker as you moved until they got close enough that they could be consistently displayed without the pixel's you didn't see a frame earlier taking their place.
again, its a bit of a mess to explain, but I'm sure most of you understand what I'm talking about
Yeah. Ive just always thought its interesting how pixel art can be skewed, shrunk, and rotated nicely in a controlled environment, but so very few games ever made use of such technique
edit-
this is probably a better example: