Thanks. The irony is I was inspired to attempt it after seeing screenshots like this of Unreal
on the Amiga:
When in fact that darker line of trees isn't a separate layer at all - it moves with the foreground. Only the very narrow horizon line and the moons move relative to the foreground.Unreal
also highlights another major drawback in scrolling on the Amiga - it has no screen wrap-around function. I presume the STE is the same? So to do continuous scrolling, you have to define a virtual screen two normal screens wide, and slide the viewport along from one to the other - but making sure that the space you're leaving behind is filled with an identical copy of the new view you're moving into. Then, when you reach the far edge of the virtual screen, you jump back to the beginning again. Unreal
doesn't have continuous scrolling though. These levels are a few screens wide, and the view just pans from left to right, and then you walk off the right-hand edge to end that level. It's all a bit cr@p really, but I didn't know this at the time - all I saw were these amazing screenshots.Agony
is more of a showcase of Amiga scrolling, and more like what I'm doing here. Though that's using the back three bitplanes of dual-playfield mode as two separate layers in themselves. I don't think I could afford to OR in another full screen of backdrop though, but I do like the fixed horizon.SotB III
is a really good Amiga scroller - multi-directional with a couple of layers in the background (though I notice the background doesn't move vertically) and some extra foreground effect, like the original, when you're running along at the lowest level.
I probably should have a crack at imitating the original SotB
with this bitplane technique, since it always seems to come up as the benchmark!