Resource centre for ZX Spectrum games
using Manic Miner and Jet Set Willy game engines
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Message: 7054
Author: rushforthian
Date: 14/02/2017
Subject: JSW Lord of the Rings Mount Doom Frodo corruption
From Andrew Broad's Technica.txt for JSW: Lord of the Rings:
> Playing as Different Characters.....
> Ever since I made these changes, there has been a slight glitch in the player's graphics in Room 33 ("Mount > Doom", formerly "The Bathroom"). I haven't put my finger on the reason for this, but it's not a serious
> problem. It's probably something to do with the fact that it's the room with the fire (former toilet) in.
Indeed. I think the problem arises because "...the contents of addresses 38496-38527 have been shunted down to 38487-38518 (leaving addresses 38519-38527 free)."
One of the addresses within that range - #9668 - is an entry point from the 'Animate the toilet in The Bathroom' routine (see the CALL at #95BB).
I believe that Andrew may have omitted to adjust the operand of that CALL command accordingly (i.e. to call up #965F) - hence the corruption?
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