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using Manic Miner and Jet Set Willy game engines
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Message: 7034
Author: rushforthian
Date: 01/02/2017
Subject: Re: JSW64 escalator-direction bug
Andrew wrote (ages ago):
> I just learned the hard way that if a JSW64 room has the "Escalators" flag on (all ramps in the room behave > as conveyors), and then you turn it off (as I've done for "Casino Royale" [20] in the easy variant of
> JSW64MM: James Bond), the flag for escalator-direction (which I incorrectly assumed was irrelevant if
> escalators were off) must be set to up, otherwise all conveyors in the room behave as right-conveyors, even > if they're actually set up correctly as left-conveyors.
It would seem that that is still the case, and the bug hasn't been fixed. (Although it doesn't affect the conveyor animation on the screen, if that is present.) However, the converse doesn't seem to apply. i.e. if the Escalator setting is Up then Right Conveyors behave as they should!
Does this mean that you can't have a Down Escalator and a Left Conveyor together on the same screen?
EDIT: The answer to that last question seems to be no; the bug only arises if the Escalator setting is Off but its (unused) direction is Down. Over and above the scenario that Andrew described, It also applies if you've simply turned the Escalator direction to Down (without having turned the Escalator on and then off).
It must be something to do with the setting of Bits 1 and 2 of Offset #FF. Bit 2 turns off Escalators, Bit 1 is set for Down and reset for Up. (Interacting somehow with the fact that the Direction is defined as 0 for a Left Conveyor?)
Perhaps JSWED should reset both bits of Offset #FF if Escalators are turned off? Or there should be a warning in the manual's 'JSW64 Good Advice' section (if it ever gets updated)?
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