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Message: 7101
Author: jetsetdanny
Date: 27/03/2017
Subject: Re: "Ma jolie" Game-engine bug / RZX walkthroughs
---In manicminerandjetsetwilly@yahoogroups.com, wrote :
Danny, I don't suppose if you recall whether the Fire cells you accidentally created within the room 'Ape Men with Metal Parts' in 'Ma Jolie' were the 'true' (defined) Fire cells for that room? If so, you might have been able to 'turn them off' by jumping off the top of 'The Mad Ramblings of Longbeard' again in a subsequent game. (Thereby further overwriting the addresses in Cavern 7's room data, and perhaps converting the errant blocks into Water cells by default).
**
EDIT: Conversely (and this is probably the more likely scenario), if the newly-created Fire cells were solid white squares with an attribute value of #FF (i.e. the unused 'Fire 2' cells for 'Ape Men...', which I've just noticed are defined by default using Flashing and Bright with White Ink on White Paper), then the process would have been irreversible!
However, you might have been able to turn the de facto Water cells that you had created in 'Ma Jolite' into Fire (2) cells by playing the game again and repeating the jump off the top of '...Longbeard'. In which case, you would have been very lucky when you played 'Ma Jolite' first time round not to have created de facto Fire cells in that case! (i.e. Willy's individual graphic bytes that wrapped beyond the screen, because of the particular frame of animation he was in during each time-frame that he was up there, somehow didn't combine to fill in all eight bits of the bytes in question!)
Ian, to answer your question I have dug up a couple of files from my archives and uploaded them over on JetSet Willy & Manic Miner Community PM system. They will allow you to investigate the matter in detail. They are:
- A ZIP file called "my_jolly_bug" with two RZX recordings of "Ma jolie" (original and first special edition) showing the bug in action in 'Ape Men with Metal Parts' (after jumping off the top of the screen in 'The Mad Ramblings of Longbeard'). I believe this is the original file I once uploaded to the File section of this Group (nowadays inactive or, for all practical purposes, non-existent) when I announced the discovery of the bug.
- An RZX walkthrough recorded back then of "Ma jolite", also showing the bug in action.
- A SNA file I created today for your convenience, after stopping the playback of the above recording in 'Ape Men with Metal Parts'.
From a look I've had at these files, it seems like the Fire cell which emerges through corruption in either of the files from "my_jolly_bug.zip" is real, i.e. it kills Willy. Therefore it is impossible to progress through the game. Conversely, the corruption in "Ma jolite" is harmless, you can move right through it and complete the game.
Anyway, I hope the files will be useful for your investigations
.
**
EDIT: Conversely (and this is probably the more likely scenario), if the newly-created Fire cells were solid white squares with an attribute value of #FF (i.e. the unused 'Fire 2' cells for 'Ape Men...', which I've just noticed are defined by default using Flashing and Bright with White Ink on White Paper), then the process would have been irreversible!
However, you might have been able to turn the de facto Water cells that you had created in 'Ma Jolite' into Fire (2) cells by playing the game again and repeating the jump off the top of '...Longbeard'. In which case, you would have been very lucky when you played 'Ma Jolite' first time round not to have created de facto Fire cells in that case! (i.e. Willy's individual graphic bytes that wrapped beyond the screen, because of the particular frame of animation he was in during each time-frame that he was up there, somehow didn't combine to fill in all eight bits of the bytes in question!)
Ian, to answer your question I have dug up a couple of files from my archives and uploaded them over on JetSet Willy & Manic Miner Community PM system. They will allow you to investigate the matter in detail. They are:
- A ZIP file called "my_jolly_bug" with two RZX recordings of "Ma jolie" (original and first special edition) showing the bug in action in 'Ape Men with Metal Parts' (after jumping off the top of the screen in 'The Mad Ramblings of Longbeard'). I believe this is the original file I once uploaded to the File section of this Group (nowadays inactive or, for all practical purposes, non-existent) when I announced the discovery of the bug.
- An RZX walkthrough recorded back then of "Ma jolite", also showing the bug in action.
- A SNA file I created today for your convenience, after stopping the playback of the above recording in 'Ape Men with Metal Parts'.
From a look I've had at these files, it seems like the Fire cell which emerges through corruption in either of the files from "my_jolly_bug.zip" is real, i.e. it kills Willy. Therefore it is impossible to progress through the game. Conversely, the corruption in "Ma jolite" is harmless, you can move right through it and complete the game.
Anyway, I hope the files will be useful for your investigations
.
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