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Message: 4389

Author: john_elliott_uk

Date: 17/08/2004

Subject: Re: JSWED 2.1.6 uploaded

 

In manicminerandjetsetwilly@yahoogroups.com, andrewbroad wrote:

So when can we expect JSW64 to reach gamma-release status? It's
becoming ever more important with several people now planning to
write games based on these engines; JSW64 deserves its own category
in my List of MM/JSW Games.

When It's Finished (tm). This basically involves working out why the
Kong Beast has stopped working in JSW64:MM.

Can Skylabs also go either right or left, as in MirrorMM?

You'd have to poke the game engine, same as in MM.

Triggers are the important one. You put a trigger before another
guardian. It will watch a byte; when that byte goes to zero, the
trigger is activated. It pokes five bytes into the following
guardian (byte 0 and bytes 4-7), and then disables itself.

I presume "guardian" here means "guardian-instance" rather
than "guardian-class".

In JSW64, there are no guardian classes; each room contains its own
instance list in expanded form. That's what makes it possible for most
of these extra guardian types to work; I considered backporting them
to JSW128 (which is quite feasible technically) but some of them would
be awkward to manage in a class+instance system.

So is the byte to be watched specified as a 16-bit address?

Yes.

So are items represented in such a way that a whole byte goes to
zero when they are collected, and switches so that a whole byte goes to zero when they are turned?

Exactly. In the case of the items, JSW64 sets a byte to zero at the
start of a game cycle, and increments it when each item is drawn, the
same as MM does for its portal check. Similarly the switch guardian's
'vertical speed' is 1 if the switch is off, 0 if it's on.

What's a WIP?

Work in Progress.

I've always found one-way switches annoying. It would be cool if you could turn back the switch in a Kong-Beast room so that the wall
closes up again.

Closing walls would have to be done with patch vectors.

So to make a gap of n character-columns, you'd have to have n
opening walls?

Yes. Either all triggered by the same switch, or each one triggered
by the previous one.

Can it work in reverse (making a moving guardian freeze or vanish),
as I seem to remember seeing in Erix1 Mode?

Yes; use a trigger to turn a blank guardian into a stopper - or into
a live guardian.

Who's Oscar?

Oscar Wilde.

Oscar Wilde: "I wish I had said that."
Whistler: "You will, Oscar; you will."

So if we invented a special dimension of guardian-types that were
drawn BEFORE the player, they would not collide with the player, and would behave according to the attribute-definitions of the block-
types.

Collisions need not be fatal, of course. The switch-drawing code
uses pretty much the same sprite-drawing code as usual, but if the
call to DRWFIX returns with the Z flag not set, the switch toggles
rather than Willy dying. For reasons of space, it's actually done
using self-modifying code; I poke a RET into the normal sprite-drawing
code, call it, and poke the RET out again.

 

 

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