dos33fsprogs/ootw/README

Another / Out-of-This World Demake for Apple II+
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
	by Vince "Deater" Weaver (vince@deater.net) 
		http://www.deater.net/weave/vmwprod/ootw/
	Disk and LZ4 routines by qkumba

+ The game "Another World" was released in 1991.
	Written by Eric Chahi.
  It was eventually ported to many systems (I played it on IBM PC).

  It even got an Apple IIgs port (the IIgs is 16-bit with fancy
	graphics and sound).  However you couldn't play it on
	earlier Apple II systems... until now.

+ I was inspired to do this by this amazing PICO-8 version of:
	https://liquidream.itch.io/another-world-survival

  and thought the Apple II lo-res palette (15 colors, 40x48 graphics)
  might be just barely enough to do it justice.

==================
Game controls:
==================

  This info appears while loading too, but if you are in an emulator with
	fast disk access it might not be on the screen long enough to see.

	D ->		- move right (twice to run)
	A <-		- move left (twice to run)
	W up		- jump
	S down		- crouch / pickup
	space		- kick / gun
	L		- charge weapon

  During the intro, you can press R to make it repeat forever.

  Hints for those who have never actually played the original game:

	+ At initial arrival, hit up a bunch of times to escape the
		tentacle monster.  On an original II w/o autorepeat
		you might have to bang on the keyboard a lot.
	+ You can kick some enemies.  Crouch-kicking is sometimes
		a bit easier than stand-kicking.
	+ When running (i.e. after pressing left or right twice)
		you can press "up" to run-jump which is faster than
		plain running.  That might be useful if you need
		to out-run something.
	+ When you get the gun, use space to fire the laser.
		You can use "L" to charge your gun for special actions.
		Charge a little bit then press "L" (or any key)
		to create a shield.
		Charge a longer time (a few seconds, when the charge
		ball gets bigger) and it will make a giant blast capable
		of destroying doors and shields.


  Note: the original Apple II had no up/down buttons, which is why
	you can also use WASD for movement.  Different emulators handle
	this differently, but if for some reason up/down is not working
	try using W/S instead.

  Joystick support: none yet?
	It should be possible, I just haven't had time to implement yet.

  Keyboard Limitations:
	Note, Apple II has simplistic keyboard support.
	In general it's not possible to read more than one key at a time.
	Additionally, on older models there's no auto-repeat unless you
		hold down the REPT key, which makes running difficult.
	This means it's really not possible to use the keyboard the
		same way as the original game (which had you do things
		like holding down spacebar to charge the gun and then
		firing when you release it.  Same for running faster
		by holding left/right and space at the same time).

==================
Development notes:
==================

Ootw Memory map:
	00	zero page
	01	stack
	02	????
	03	nibble table/disk data
	04-07	GR page0
	08-0b	GR page1
	0c-0f	background  ($c00 = disk load buffer)
	10-13	background overlay
	14-16	loader
	17-bf	program-data (41.25k)
	bc-bf   earthquake background (shifted)
	c0-cf	I/O
	d0-ff	ROM


Intro Memory map:
	00	zero page
	01	stack
	02	????
	03	nibble table/disk data
	04-07	GR page0
	08-0b	GR page1
	0c-0f	offscreen data  ($c00 = disk load buffer)
	10-13	offscreen data2
	14-16	loader
	17-89	program/compressed-data (30.25k)
	90-bf	currently decompressed level data (12k)
	c0-cf	I/O
	d0-ff	ROM


Intro Memory squeeze!

	10,748 over	all graphics in
	10,734 over	remove extraneous blank bg image
	 8,658 over	re-arrange memory map, 42k avail now
	 8,562 over	move gr_make_quake out of common code
	 8,374 over	remove extraneous code (mostly put_sprite_flipped)
	 5,469 over     allow changing bg on fly in sequence
	 4,122 over	modify cyan frames to be on fly
	 2,749 over	do same for zappo routines
	 2,493 over	squish disk loader vars to page 3
	 2,165 over	horrible hack to auto-go to next image in sequence
	 2,114 over	move bg loading into seq
	 2,053 over	make elevator indicator a loop
	 1,347 over	use LZ4 instead of RLE

Gave up, see if we can compress in chunks and decompress, sort of like
my chiptune player does.


Let's take a 12k region of memory = $3000
	$C000 - $3000 = starting at $9000


ID1 =	1461		2143\
ID2 =   1759		2687|--- together in 01
ID3 =	1195		1879/
ID4 =   2514		8280\--- in 04
ID5 =	1947		3492/
ID6 =	2584		3610\ --- in 06
ID7 =   2834		3606/
ID8 =	3705		4918 | -- in 08
ID9 =	4494		5901\  -- in 09
ID10 =	3397		5558/
	=====          ======
	25890             12k


ootw memory squeeze:
	after full rope sequence in:	23065
	make transparent overlays:	13971
	add end-of-l1 cutscene:		26464
	make transparent overlays:	17821
	add in rest of end cutscene	23906
	make those transparent		21236


ootw2 memory squeeze:
	before intro			3872
	after intro			9234




L2 Memory map:
	00	zero page
	01	stack
	02	????
	03	nibble table/disk data
	04-07	GR page0
	08-0b	GR page1
	0c-0f	offscreen data  ($c00 = disk load buffer)
	10-13	offscreen data2
	14-16	loader
	

	c0-cf	I/O
	d0-ff	ROM