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using Manic Miner and Jet Set Willy game engines
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Message: 6932
Author: ian.rushforth
Date: 14/11/2016
Subject: Re: Broadsoft Lifts v0.2: Hex-editor type-in
Further to my previous message, I suppose the routine (as it currently stands) is more 'future-proofed' to allow for potential tweaking.
e.g. if the 'CP #FE' was changed to 'CP #E0', then the lift might be made to 'hoover up' Willy when he is directly under it (moving him rapidly from beneath the lift to the top of it, in a single time-frame)?
That wouldn't be possible without checks being made at 'either end' of the potential range of values of A.
**
One other query - doesn't the Broadsoft Lifts routine cause odd iteractions with ropes? At the end of the rope-moving code (at #9130), there is a jump to #91B6.
But with the Broadsoft Lifts patch in place, #91B6 has been edited to call up the above routine, which could thus be 'fooled' into thinking that the rope is a Broadsoft Lift, if Bit 4 of Byte 1 of the rope is set - which will happen periodically, as Byte 1 is the rope's Animation Frame Index which varies as the rope swings.
N.B. Arrows wouldn't be affected - being briefly considered (via the jump at #90CC) but discounted by the Lifts routine - as Byte 1 of an arrow's definition is unused (so Bit 4 should be reset by default).
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