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using Manic Miner and Jet Set Willy game engines
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Message: 6838
Author: jetsetdanny
Date: 12/04/2015
Subject: Re: Question about inserting patch vectors in JSW64
John, I have tried to work with JSWED hex editor a little, but have failed totally. I think I'd better ask you some basic questions before wasting my time on trying to do something which may be totally impossible.
Here's what I've been trying to do. I would like to have a room in which a text would be printed in, say, the upper part of the room. I would leave just Air in that part of the room and not use it in any way during gameplay (no guardians, no items, no Willy, nothing, just the printed text).
I would like to use JSW64 variant V.
Let's have a look at room 000 "The Off Licence".
In JSWED I cleared it of guardians and items and most of the non-Air cells, I filled it with Air and only left one row of Earth cells at the very bottom. I set the starting portal (Willy) at the bottom, so that he stands on the Earth cells.
Working on memory bank 1 (IS THIS CORRECT?) I changed the value of #C0FB to #00C1 in order to point to the address #C100 - the beginning of what I believe is the free space in this room.
I changed the addresses between #C100 and #C10C as follows:
DD2128C1 11E140 0E10 CD8096 C9 (no spaces in JSWED, of course; I put spaces here to separate what I perceive as different parts of the code);
and the addresses between #C128 and #C137 as follows:
54657374546573745465737454657374
in order to achieve the following:
Print at 7,1 the text "TestTestTestTest" and then return to the regular room routine.
I tried to do what I did before in "JSW: The 2010 Megamix", where I successfully used the code:
DD21 [two bytes showing where the beginning of the text data is] 11 [two bytes showing where the start of the text will be printed on the screen] 0e [one byte showing the length of the text] CD8096 [reference to the printing routine, I believe]
for printing a text on the screen,
followed by C9 (Ret).
I have failed to achieve anything. The result is that nothing is printed, upon entering "The Off Licence" after starting the game there is a residue of the Press Enter to Start message (interspersed with the number of items collected, namely: "Press ENTE000o Star "), then when you exit to "The Bridge", "The Bridge" is fine, but then when you return to "The Off Licence", the name of the room is still "The Bridge".
Is it possible at all to do what I was trying to do, that is print a text in a portion of the room which is not used for gameplay, so that it stays there while you are in the room? If it can be done, how can I do it?
Any help will be appreciated :-) .
Daniel
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