It's related to how engine(s) draw things discussion thus I'll attach my post here.
Anyway, today I've noticed another proof that seems to confirm my (newest) theory that OpenXcom draws things like MapView does (except negative "tile y offset" value), which is in two cases different than original engine.
a) Step backward (perhaps it should go to bugs forum?
):
Pieces that are raised to 24 voxels (they're sitting in wall slots) are overlapped by tiles level above. Details: there's no tile at the same grid, or "before" it level above. And they should overlap next tile to it, which means tile "after" level above (but it's opposite). I've been testing super-cool-looking cut-off pilot's compartment <==> cargo bay (advanced usage of engine's features
). See attachment (top - OpenXcom/MapView, bottom - original engine). Of course, this should happen with "tile y offset: 24" only, because 24
is another level, but is displayed on level is placed as well, but when switched to level above, visually acts like object placed there (without "shadow casting", only proper drawing order - see original engine). Would be really great to make engine display stuff this way.
b) Step forward:
On a side (brighter) note: I've tried to move ground tiles one pixel down, and since it's not possible via frame editing - 32x40 limit - and that means one pixel less of height thus four pixels(!) would be lost, so I've tried to use "Print Level Adjust" (Tile Y offset) feature... Unfortunately it's possible to move frame down only with MapView (255 value is treated as -1). Both engines treat it as 255 up thus tile isn't visible at all. I thought it's working in similar way as "Terrain Level" (Unit Y offset): 256 - 8 (going up), and 0 + 8 (going down), but it looks like not... So I figured out I'll move walls one pixel up... and shit happened (you can see where walls are that are under it) so, I've tested it with OpenXCom... Awesome!
Of course, we shouldn't forget about this (step forward):
On a side note: I'm glad you've fixed overlapping issue...
(top - original engine, bottom - OpenXCom)
Dunno, to what it's related. Maybe it's Daiky's fix?
----------------------EDIT
By the way, funny side effect of odd HWP's behavior on hilly stuff