Resource centre for ZX Spectrum games
using Manic Miner and Jet Set Willy game engines
Archive of the
Manic Miner & Jet Set Willy Yahoo! Group
messages
|
|
|
|
|
Message: 5083
Author: john_elliott_uk
Date: 18/11/2005
Subject: Skylabs that keep in one column
--- In manicminerandjetsetwilly@yahoogroups.com, "Igor Makovsky"
> How to let this work, John? So skylabs won't change their Y
Since it's functionality provided by a patch vector, JSWED can't
> coordinate.
edit it. So at the moment your only option is to make sure the patch
vector is included, patch the guardian vectors (as described in my
previous post, or at the bottom of this one), set up as a normal
skylab and then change the first byte of the guardian definition from
08 to 78. JSWED won't draw the guardian but (if you've set it up
correctly) JSW64 itself will.
> John, you ignore again my question about JSWED.
Whoops. I keep forgetting to answer.
> - Why JSWED doesn't show every 8th sprite in the rows when choosing
It's caused by a bug. A very silly bug that I should have found and
> among sprites for a guardian?
fixed years ago. Sorry.
Here's how to apply the non-sideways-moving skylabs patch to a
vanilla JSW64 game (ie, one that was upgraded from JSW48):
1. Reserve a page of memory.
2. Put the following bytes at the start of that page:
dd 7e 01 0f 0f 0f 0f e6 0f fe 09 38 02 f6 f0 32 61 ff c3 2c ff
-- the other 245 bytes of the page are now wasted, unless you want to
put some other patch code in them.
3. Change the following bytes:
ECA6 to 00
ECA7 to the number of the page you reserved.
ECC6 to D6
ECC7 to 91
|
|
|