They're compressed representations of a sequence of pixels captured from the framebuffer at a chosen time by invoking an application with the CTRL-ALT-PrtScrn command, which are stored with 32-bit color precision etc etc.
OK, they're screenshots. This one is me messing around with a perspective I've never used before: Isometric
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Apparently I fed ChIkEn.
This amuses me, because that explains where my sammich disappeared to yesterday…Don't get me wrong, I love the Legend of Zelda games, I just don't like the art style as much, being more from the Bahamut Lagoon/Tales of Phantasia/Sword of Mana crowd. :P
Getting sprite perspective right is what I'm working on now. Making 2D platformers doesn't offer much in the way of practice in that area, so I thought a nice little Isometric game would help. I've been getting into the habit of using guidelines to get perspective right.