Resource centre for ZX Spectrum games
using Manic Miner and Jet Set Willy game engines
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Message: 6945
Author: ian.rushforth
Date: 16/11/2016
Subject: Re: Broadsoft Lifts v0.2: Hex-editor type-in
I wrote:
"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)."
Interestingly enough, whilst Byte 1 is unused for arrows, in the original JSW code it is assigned a non-zero value, for both left and right arrows. Fortunately, that value is '#06', and so Bit 4 is reset.
(I wonder what the significance of the '06' is? Byte 6 of a rope's definition is similarly unused-but-assigned-a-non-zero-value: namely '#83'. Which coincides with the value that Byte 0 assumes when the rope is swinging from left to right, so there is at least a rationale for it, in terms of perhaps having been placed there by Matt Smith during early testing of the rope-moving code?)
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