Thanks to whoever posted those screenshots and comparisons, we now have a good idea as to how this will turn out.
I'm more inclined to believe that it's based off the iOS/Android versions, sadly. Here are the tell-tale signs:
1) The shadows are mere circles. On PS2 they are more detailed than that.
2) The foliage has been decreased -- this is something I noticed while playing DQVIII on Android (a Moto X) last year, where I took a few comparison shots.
3) Terrain is simpler and a few details are missing, as was the case on iOS/Android. The wooden fences were definitely removed from the iOS/Android version, for example.
Once we get some town screenshots and night screenshots we'll be able to have a better look at the lighting as well. On iOS/Android the lighting is pretty flat, and some details during the evening were removed. For example, windows wouldn't shine a bright yellow at night, they would remain identical to how they looked during the day. Also: the moving sun in the sky -- something that always reminded me of Ocarina of Time -- was completely removed if I remember correctly, as well as the cool lens flare effect you'd get for staring at it.
I'd like to be wrong, but I'd rather aim low than get my hopes up!
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I wouldn't jump to conclusions and blame the 3DS for any of these visual concessions. It's a capable system for this kind of game, and the iOS/Android port ran like a dog on far, far more powerful hardware, hardware that can easily do the best PS2 has to offer in far higher resolutions at at smoother framerates.
2013's iPhone 5s has an awful lot of processing power. The Apple A7 delivers seven times the single-threaded CPU performance of the PS Vita's Cortex A8 CPU, and the 5s was the first device on the market with a PowerVR Series 6 GPU, a whole generation leap above the Vita's seres 5 GPU which was similar to the iPad 3's.
Yet TOSE's Dragon Quest VIII port looked worse than the PS2 original, and ran at about 20fps :/
Where are the 'but 3DS unequivocally more powerful than the PS2' people now? Still, portable DQVIII. Tis a beautiful thing.
Just saw this. It's just an unfair comparison, really. You're comparing a game made to fit the PS2's architecture and developed on a big budget and by a large team at Level-5 to a quick and easy low budget port that may be running on an engine that doesn't suit 3DS's different hardware makeup (likely by TOSE).
It'd be like claiming that the Vita isn't much more powerful than the Wii off the basis of New Little King's Story and its noticeable framerate drops and lower quality shadows among other things. Different teams, different budgets, different hardware makeups. Ports of bespoke exclusives to similarly-powered hardware don't necessarily turn out well. See: Bayonetta 360 to PS3 as an extreme example. It was basically developed as if it were a 360 exclusive, using that system's strengths. Games which took both the PS3/360's hardware makeup into consideration fared much better, at the expense of losing features which suit either the 360 or the PS3.