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
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Message: 465
Author: sj_hill
Date: 02/08/2000
Subject: Re: ?tioning the mind of a genious
> isn't it odd how the jsw gamestores bitmaps for the air blocks
> engine
> in each
room
I'm no expert on this, but I imagine that M. Smith's
technique wastes memory but simplifies (and speeds up) the
game engine.
To create a room, the engine
presumably races across the screen copying the appropriate
8x8s (and their attributes) to their correct
positions. It does the same thing irrespective of whether
the block is air, earth, fire or water.
The
alternative is to spend time blanking out the entire screen,
then move across the screen copying the appropriate
8x8s (and attributes), except when the block is air,
in which case do nothing except set the attribute.
Searching for this exception would probably add as much
code as the 8x64 bytes the blank air 8x8s take up.
Also it would take extra time to blank the entire
screen.
Of course, anyone out there who has actually looked
at the disassembled game engine will have a better
idea!
Stuart.
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