deluded said:
That sounds useful.
I guess it's just nearest pixel rather than bilinier.
Cheers for your help!
yeah it's coarse scaling. but if you're using it for quick zoom effects (which, has anyone even done this before on gp2x? sounds sweet.) that might look fine.
for a pretty static image like a background, 640x480 scaled down 50% looks pretty clean, unless there's text on screen. i think hex-a-hop was ported like this.
and if the image moves and the frame rate stays high...i don't quite know how to explain it but i bet that the different pixels getting drawn or not drawn will change each frame, so over a few frames, the information does end up being there. like standing behind a screen door and moving sideways quickly...the mesh disappears.
for totally 2d game, this could be shimmery and weird, for 3d, it could work better, but i'm just guessing.
obviously there is the issue of rendering a picture in which 75% of the information is getting discarded...but hey, the scaling is free. anyway, good luck.
side note: i think the chip used to play movies can do smooth scaling. i'm fuzzy on the details now, but this is what i sort of remember people saying. i don't think it's bilinear or anything pixel-related but instead more of an analog scaling. anyway it's not something we have access to unfortunately.