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using Manic Miner and Jet Set Willy game engines
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Message: 6987
Author: rushforthian
Date: 25/12/2016
Subject: Re: JSWED 2.3.1: Andrew's comments (Chapters 14 to 17)
John Elliott wrote (in the JSWED Manual):
> Make sure the Solar Power beam doesn't go off the screen, or the
> game engine will crash. Block it with Earth if necessary.
I'm not sure that the above causes the game engine to crash, but it can seemingly cause strange effects...
If the Solar Power beam extends horizontally off the left-hand side of the screen, then it appears on the right-hand side (one cell-row higher). It can then be deflected by itself (by the part that was previously drawn).
Whereas if the beam extends vertically below the bottom of the screen, then it wraps back to the top, except that subsequent elements are written at the level of the primary (Empty Room) attribute buffer, rather than the secondary (Occupied Room) attribute buffer. This time, not only does the beam deflect itself sideways when it encounters a previously-drawn part of itself, but the cells that are coloured by the solar beam can change their behaviour. Some of them don't cause Willy's air supply to be depleted rapidly when he touches them (as a solar beam should), but instead they act as Water cells, allowing Willy to stand on them!
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