From: Mischa Poslawsky <nemesis@shiar.org>
Date: Mon, 23 Aug 1999 10:21:32 +0000 (+0200)
Subject: version 0.6: logo, bottom stats bar, 5 random levels
X-Git-Url: http://git.shiar.net/nemesis.git/commitdiff_plain/6182b2a8db0e125b903be3ca44c3a8227fdf4f9f

version 0.6: logo, bottom stats bar, 5 random levels

* play field increased to full screen instead of 3/4
+ bottom eight lines used for score (etc) display
- no more solid levels, enemies are placed at random
+ enemies appear every x turns (depends on level)
# fixed bullets so they don't disappear at 3/4 of the screen
* A LOT of optimizations both in speed and size!!
+ enemy type, frequency, and number specified per level
+ bottom score bar displays score, lives and icons (to be used later)
* smarter enemy handling (so enemies have different sizes)
+ bottom bar divided from playing field by a horizontal line
+ five levels (and five enemies) made
# game vars reset at start and game over
+ NEMESIS LOGO displayed at startup!! (also, program grew 350bytes ):
+ version/credit-string displayed below logo: v0.6.820 by shiar (ICQ#)
---

diff --git a/nemesis.z80 b/nemesis.z80
index cb0f3eb..35f36c9 100644
--- a/nemesis.z80
+++ b/nemesis.z80
@@ -1,6 +1,5 @@
 	.include "asm86.h"
 	.include "ti86asm.inc"
-	.include "ti86abs.inc"
 
 	.org _asm_exec_ram
 
@@ -9,9 +8,8 @@
 	.dw $0001
 	.dw Title
 	.dw spr_ship
-Title:	.db "Nemesis v0.5.725 by Shiar",0
-Start:
-	jr init
+Title:	.db "Nemesis v0.6.820 by Shiar",0
+Start:	jr init
 
 just_fired	= $c0f9		;byte
 temp1		= $c100		;word
@@ -23,10 +21,33 @@ init:
 
 ;---------------------- main menu ---------------------------------------------
 
-;---------------------- game setup --------------------------------------------
+LogoPut:
+	ld hl,logo_nemesis	;from...
+	ld de,$FC00+16		;...to one line from top
+	ld a,19			;19 rows
+LogoLoop:
+	ld bc,16		;set screen width
+	ldir			;display one line
+	dec a			;decrease line-counter
+	jr nz,LogoLoop		;repeat when counter is not yet zero
+
+menutext:
+	ld  hl,$1608		;just below logo
+	ld  (_penCol),hl
+	ld  hl,txt_about	;display "by Shiar (ICQ#43840958)"
+	call _vputs
+
+	ld  hl,$0705		;located one row above bottom
+	ld  (_curRow),hl	;go there
+	ld  hl,txt_1player	;display "ONE PLAYER"
+	call _puts
+	ld  hl,$0706		;below oneplayer text
+	ld  (_curRow),hl
+	ld  hl,txt_2players	;display "TWO PLAYERS"
+	call _puts
 
-play_game:
-	call Next_level
+	call _getkey		;wait for keypress
+	call New_level		;prepare level
 
 ;------------------------------------------------------------------------------
 ;---------------------- game loop ---------------------------------------------
@@ -37,23 +58,24 @@ game_main_loop:
 	inc (hl)
 
 Clear_screen:
-	xor a
-	ld  hl,GRAPH_MEM+(16*12)
-	ld  b,a
+	xor a			;empty bitmask
+	ld  hl,GRAPH_MEM	;screen location (top left)
+	ld  b,$E0		;loop 0E0h = 224 times = 256-32 for score-bar)
 clearloop:
+	ld  (hl),a		;clear four times (total = 224*4 = 896 bytes)
+	inc hl
 	ld  (hl),a
 	inc hl
 	ld  (hl),a
 	inc hl
 	ld  (hl),a
 	inc hl
-	djnz clearloop
+	djnz clearloop		;repeat 224x
 
 check_exitkey:
 	ld  a,%00111111		;<exit> pressed?
 	out (1),a
-	nop
-	nop
+	nop \ nop
 	in  a,(1)
 	bit 6,a
 	jr  z,quit		;yes: quit game
@@ -68,7 +90,7 @@ game_stuff:
 	call Enemies_hit	;check for collision with enemies
 
 	call Display_Screen	;display all
-	halt \ halt \ halt	;delay
+	halt \ halt		;delay
 	jr   game_main_loop	;loop
 
 quit:	ret
@@ -76,21 +98,17 @@ quit:	ret
 ;---------------------- display -----------------------------------------------
 
 Display_Screen:
-	ld  a,64		;Display Image
-	ld  hl,GRAPH_MEM+(16*12)
-	ld  de,$fc00
+	ld  hl,GRAPH_MEM	;from storage (top left)
+	ld  de,$fc00		;to screen (top left)
+	ld  a,56		;display height = 64 bytes (minus 8 for bar)
 displayloop:
-	ld  bc,12
-	ldir
-	inc de
-	inc de
-	inc de
-	inc de
-	dec a
-	jr  nz,displayloop
+	ld  bc,16		;display width = 16 bytes (16*8bits=256pixels)
+	ldir			;16x de >> hl
+	dec a			;next line
+	jr  nz,displayloop	;loop 64x
 
-	ld  hl,$1006		;Display Score
-	ld  (_curRow),hl
+	ld  hl,$3a6b		;Display Score
+	ld  (_penCol),hl
 	ld  hl,(timer)
 	ld  h,0
 	jp  _D_HL_DECI
@@ -108,22 +126,23 @@ Handle_Ship:
 
 	cp  34			;last explosion frame?
 	jr  c,exploding_you	;not yet: display explosion
-	cp  54			;delay finished?
+	cp  40			;delay finished?
 	jp  z,game_over		;yes = game over
 	ret			;don't display anything
 
 ok:
 	ld  a,%01111110
 	out (1),a
-	ld  hl,y
+	nop \ nop
 	in  a,(1)
+	ld  hl,y
 	rra
 	ld  b,a
 
 	jr  c,no_down
 	ld  a,(hl)
 	inc a
-	cp  73			;y < 73
+	cp  50			;56-6 = bottom of screen
 	jr  z,no_down
 	ld  (hl),a
 no_down:
@@ -131,15 +150,15 @@ no_down:
 	rr  b
 	jr  c,no_left
 	ld  a,(hl)
-	dec a
-	jr  z,no_left		;x > 0
+	sub 1			;<dec 1> doesn't affect c-flag
+	jr  c,no_left		;-1 = left side
 	ld  (hl),a
 no_left:
 	rr b   
 	jr  c,no_right
 	ld  a,(hl)
 	inc a
-	cp  89			;x < 89
+	cp  122			;128-6 = right side
 	jr  z,no_right
 	ld  (hl),a
 no_right:
@@ -148,9 +167,8 @@ no_right:
 	rr  b
 	jr  c,no_up
 	ld  a,(hl)
-	dec a
-	cp  15			;y > 15
-	jr  z,no_up
+	sub 1			;<dec a> doesn't affect carry-flag
+	jr  c,no_up		;-1 = top of screen
 	ld  (hl),a
 no_up:	ld  ix,spr_ship01
 
@@ -253,10 +271,10 @@ scan_bullets:
 bullet_type1:
 	ld  a,(hl)		;d = X
 	inc a			;move right
-	cp  $5a			;off screen?
+	cp  121			;off screen? (x=127-5-1)
 	jr  z,remove_bullet
 	inc a			;move right
-	cp  $5a			;off screen?
+	cp  121			;off screen?
 	jr  z,remove_bullet
 	ld  (hl),a		;save new pos.
 	ld  d,a
@@ -304,12 +322,13 @@ hit_enemies:			;Hits with normal enemies
 	dec hl
 	ld  a,(hl)		;occ
 	ld  b,a			;push occ
-	srl a
-	srl a			;occ/4 = HP left
-	jr  nz,hpleft
-	ld  (hl),$01		;set to explode
+	and %11111100		;occ/4 = HP left	;<srl a\srl a
+	jr  nz,hpleft		;not zero -> jump
+	ld  (hl),%01		;set to explode
 	inc hl
+	ld  b,(hl)		;save enemy type
 	ld  (hl),a		;explosionFrame 0
+
 	pop hl
 	ret
 
@@ -331,14 +350,27 @@ nohit:	pop hl
 ;--------------------------- level events -------------------------------------
 
 Level_event:
-	ld  a,(nextevent)
-	dec a
-	ld  (nextevent),a
-	or  a
-	ret nz
+	ld  hl,nextevent	;time to next event	<ld  a,(nextevent)
+	dec (hl)		;decrease counter	<dec a
+	ld  a,(hl)		;look at counter	<ld  (nextevent),a
+	or  a			;has it reached zero?
+	ret nz			;nope: get outta here!
+
+	ld  a,(eventtime)	;enemy frequency (lvl)
+	ld  (nextevent),a	;set time to next event
+	ld  hl,eventleft
+	dec (hl)		;update enemy-counter
+
+	ld  a,(hl)		;look at counter
+	or  a			;has it reached 0?
+	jp  z,Next_level	;yes: level finished
+	dec a			;has it reached 1?
+	jr  nz,do_event		;nope: wait for enemies to leave
+	inc hl			;nextevent located behind eventleft
+	ld  (hl),109		;set delay
+	ret			;don't place any more enemies
 
 do_event:
-	ld  hl,(curevent)
 	ld  de,enemies-4
 chk_noenemy:
 	inc de
@@ -349,12 +381,11 @@ chk_noenemy:
 	or  a			;0 = no enemy present
 	jr  nz,chk_noenemy
 
-	ld  a,(hl)		;type
-	ld  hl,enemy01
+	ld  a,(eventenemy)	;enemy type to place (lvl)
+	ld  hl,enemy01		;enemy 1 specs
 	ld  c,a
-	ld  b,0
-	add hl,bc
-	add hl,bc
+	ld  b,0			;bc = enemy nr.
+	add hl,bc		;add 2*bc
 	add hl,bc		;hl = enemy specs
 	ld  a,(hl)		;load hitpoints+occ of this enemy class
 	ld  (de),a		;occ
@@ -362,30 +393,16 @@ chk_noenemy:
 	inc hl
 	inc de
 	ld  a,(hl)		;load movement+type of this enemy class
-	ld  (de),a		;type
-
-	inc de
-	ld  a,$5a		;appear at right edge of screen
-	ld  (de),a		;x
-	inc de
-
-	ld  hl,(curevent)
-	inc hl
-	ld  a,(hl)
-	ld  (de),a		;y
-
-	inc hl			;@ next event
-	ld  a,(hl)
-	cp  $ff			;255 = end marker
-	jp  z,Next_level
-	ld  (nextevent),a	;else time to next event
-
-	inc hl
-	ld  (curevent),hl	;update pointer
-
-	or  a			;no delay
-	jr  z,do_event
-	ret			;no more events for now
+	ld  (de),a		;enemy type
+
+	inc de			;_________
+	ld  a,122		;appear at right edge of screen (128-6)
+	ld  (de),a		;= x-position
+	inc de			;_________
+	ld  a,51		;random number <51
+	call Random		;create!
+	ld  (de),a		;= y-position
+	ret
 
 ;--------------------------- enemy fires --------------------------------------
 
@@ -480,7 +497,7 @@ remove_ebullet:
 
 Handle_enemies:
 	ld  hl,enemies
-	ld  b,nrenemies		;loop 20x
+	ld  b,nrenemies		;handle all enemies
 
 handle_enemy:
 	push bc
@@ -500,15 +517,17 @@ moving_enemy:			;occ "moving" 3
 
 normal_enemy:
 	inc hl
-	ld  a,(hl)		;type
-	and %11100000		;move-type
-	add a,b			;add move bit from occ
-	ld  b,a			;save in b
-	ld  a,(hl)		;type
-	add a,a
-	add a,a
-	add a,a
-	ld  c,a			;type*8 = offset
+	push hl
+
+	ld  e,(hl)		;e = enemy type
+	ld  d,0			;de = e
+	ld  hl,sprites		;hl = @sprites offset-table
+	add hl,de		;points to offset of current enemy offset
+	ld  e,(hl)		;de = @enemy offset
+
+	ld  ix,spr_enemy01	;first enemy sprite
+	add ix,de		;add offset for current enemy
+	pop hl
 
 	inc hl
 	ld  a,(hl)		;x
@@ -548,32 +567,16 @@ movedown:
 ymove_done:
 	dec hl			;@x
 	ld  (hl),d		;store new x
-	ld  ix,spr_enemy01
-	ld  b,$00
-	add ix,bc
 
-;	push hl			;save registers
-	push de
-	call drw_spr		;display
+	push de			;save registers
+	call drw_spr		;display sprite @ix
 	pop  de			;restore (destroyed by drw_spr)
-;	pop  hl
-
-;	dec hl
-;	ld  b,(hl)		;type
-;	and %00011111		;enemy class
-;	ld  hl,enemy01		;all enemies' specs
-;	inc b			;next enemy's specs
-;	ld  c,$00
-;	add hl,bc
-;	add hl,bc
-;	add hl,bc		;go there
-;	dec hl			;last byte of this enemy's specs
-
-	ld  a,$ff		;fire frequency
+
+	ld   a,$ff		;fire frequency
 	call Random		;random value < a
-	dec a			;fire if 1
+	dec  a			;fire if 1
 	call z,Enemy_fires	;fires bullet
-	jr   next_enemy
+	jr   next_enemy		;finished
 
 remove_enemy:
 	pop hl
@@ -615,7 +618,7 @@ check_collision:
 	push hl
 	ld  a,(hl)
 	and %00000010
-	jr  z,check_next	;2/3 = ok
+	jr  z,check_next	;2 or 3 = ok
 
 	inc hl
 	inc hl
@@ -652,21 +655,86 @@ check_next:
 	djnz check_collision
 	ret
 
+;--------------------------- game over ----------------------------------------
+
+game_over:
+	call _clrLCD		;clear screen
+	ld  hl,$0603
+	ld  (_curRow),hl	;center
+	ld  hl,txt_gameover
+	call _puts		;display "GAME OVER"
+
+	ld  b,$20
+wait2:	halt \ halt
+	djnz wait2		;delay
+	call _getkey		;wait for keypress
+
+;--------------------------- new game -----------------------------------------
+
+New_level:
+	xor a			;a=0
+	ld  hl,x		;begin position x=...
+	ld  (hl),a		;...=a=0=left
+	inc hl			;y=...
+	ld  (hl),24		;...=24=middle
+	ld  (level),a		;reset level nr
+	ld  (score),a		;reset score
+	ld  hl,level01-3	;set level pointer to level#1
+	ld  (levelp),hl		;reset level pointer
+
 ;--------------------------- next level ---------------------------------------
 
 Next_level:
-	ld  hl,Leveldata+1	;reset level data
-	ld  (curevent),hl
+	ld  hl,level
+	inc (hl)		;increase level nr.
+	ld  a,80
+	ld  (nextevent),a	;time to first enemy appearance
+
+	ld  hl,(levelp)		;level pointer
+	inc hl
+	inc hl
+	inc hl			;update to point to next level
+	ld  (levelp),hl		;save
+
+	ld  a,(hl)		;load new level-enemy type
+	ld  (eventenemy),a	;set level-enemy
+	inc hl
+	ld  a,(hl)		;load new appearance-time
+	ld  (eventtime),a	;set
+	inc hl
+	ld  a,(hl)		;load nr of enemies in this level
+	ld  (eventleft),a	;set nr of events left
 
+	xor a
+	ld  (timer),a		;reset time
+
+;--------------------------- setup game ---------------------------------------
+
+game_setup:
 	call _clrLCD		;clear screen
+	ld a,%10111011
+	ld  hl,$fc00		;screen location (top left)
+	ld  b,0			;b = 0 (loop 0-1 = 0FFh = 256 times)
+clearloop2:
+	inc a
+	ld  (hl),a		;clear four times (total = 256*4 = 1024 bytes)
+	inc hl
+	ld  (hl),a
+	inc hl
+	xor $ff
+	ld  (hl),a
+	inc hl
+	ld  (hl),a
+	inc hl
+	xor $ff
+	djnz clearloop2		;repeat 256x
+
 	ld  hl,$0703
 	ld  (_curRow),hl	;center
 	ld  hl,txt_level
 	call _puts		;display "LEVEL "
 
 	ld  a,(level)
-	inc a			;increase level nr.
-	ld  (level),a
 	ld  l,a
 	ld  h,$00
 
@@ -677,87 +745,108 @@ Next_level:
 	add a,'0'
 	call _putc		;display second digit
 	ld  a,b
-	call _putc		;display first digit
+	call _putmap		;display first digit
+
+	ld  hl,$0904
+	ld  (_curRow),hl	;display lives left below level nr
+	ld  hl,txt_lives	;bar text: "Lx0"...
+	ld  a,(lives)		;lives left
+	add a,'0'		;make value
+	ld  (txt_lives+3),a	;add to text
+	call _puts		;display the string
 
 	ld  b,$20
 wait:	halt \ halt
 	djnz wait		;delay
 	call _getkey		;wait for keypress
-	jr  game_setup		;prepare display and vars
-	ret
 
-;--------------------------- game over ----------------------------------------
-
-game_over:
-	ld  hl,Leveldata+1	;reset level data
-	ld  (curevent),hl
-
-	call _clrLCD		;clear screen
-	ld  hl,$0603
-	ld  (_curRow),hl	;center
-	ld  hl,txt_gameover
-	call _puts		;display "GAME OVER"
+	ld  ix,spr_icon00	;display icons
+	ld  de,$1802		;bottom left
+	call drw_spr
+	ld  ix,spr_icon00	;display icons
+	ld  de,$2002		;bottom left
+	call drw_spr
+	ld  ix,spr_icon00	;display icons
+	ld  de,$2802		;bottom left
+	call drw_spr
+	ld  ix,spr_icon00	;display icons
+	ld  de,$3002		;bottom left
+	call drw_spr
+	ld  ix,spr_icon00	;display icons
+	ld  de,$3802		;bottom left
+	call drw_spr
 
-	ld  b,$20
-wait2:	halt \ halt
-	djnz wait2		;delay
-	call _getkey		;wait for keypress
-	jr  game_setup		;prepare display and vars
-	ret
+	ld  hl,GRAPH_MEM	;from storage (top left)
+	ld  de,$fc00+(56*16)	;to screen (top left)
+	ld  a,8			;display height = 64 bytes (minus 8 for bar)
+displayloop3:
+	ld  bc,16		;display width = 16 bytes (16*8bits=256pixels)
+	ldir			;16x de >> hl
+	dec a			;next line
+	jr  nz,displayloop3	;loop 8x
+
+	ld  hl,$3a00		;display Lives
+	ld  (_penCol),hl	;bottom left
+	ld  hl,savestr+2
+	ld  (hl),'L'
+	inc hl
+	ld  (hl),'x'
+	inc hl
 
-;---------------------- setup game --------------------------------------------
+	ld  a,(lives)		;nr of lives in a
+	add a,'0'		;make digit
+	ld  (hl),a
+	dec hl \ dec hl
+	call _vputs		;display on screen
 
-game_setup:
-	call _clrLCD
-	ld  hl,$1005
-	ld  (_curRow),hl
-	ld  hl,txt_score	;display "SCORE"
-	call _puts			;display texts
+	ld  hl,$fc00+(16*57)	;56 rows down = eight rows from bottom
+	ld  b,15		;draw 16x (screen width)
+drawline:
+	ld  a,%11111111		;horizontal line mask
+	ld  (hl),a		;draw one piece of the divider-line
+	inc hl			;move right (8 pixels = 1 byte)
+	djnz drawline		;repeat (16bytes * 8pixels =128= screen width)
 
-	xor a
-	ld  (timer),a			;reset time
-	ld  (level),a			;level 1
-	ld  hl,Leveldata+1
-	ld  (curevent),hl		;reset level
-	ld  hl,(Leveldata)
-	ld  (nextevent),hl
 					;ret
-;---------------------- exit --------------------------------------------------
+;--------------------------- exit ---------------------------------------------
 
 exit_game:
 	ret
 
 ;--------------------------- putsprite ----------------------------------------
+;--------------------------- de =(X,Y) ----------------------------------------
 
 offsets_table:
-	.db 128,64,32,16,8,4,2,1
+	.db 128,64,32,16,%1000,%0100,%0010,%0001
 drw_spr:
-	ld  a,d
-	and 7
-	ld  hl,offsets_table
-	ld  c,a
-	ld  b,0
-	add hl,bc
-	ld  a,(hl)
+	ld  a,d			;a = X
+	and %00000111		;a = X mod 8 = bit nr. to mask
+	ld  hl,offsets_table	;pixel mask table
+	ld  c,a			;bit nr.
+	ld  b,0			;word
+	add hl,bc		;add to table
+	ld  a,(hl)		;a = pixel mask
+	ld  (_smc1+1),a		;alter pixel mask
 	ld  (_smc1+1),a
 
-	ld  (_smc1+1),a
-	ld  hl,GRAPH_MEM
-	ld  a,e
-	add a,a
-	add a,e
-	add a,a
+	ld  hl,GRAPH_MEM	;save-location
+	ld  a,e			;y-coord
+	add a,a			;y*2
+	add a,a			;y*4
+	add a,a			;y*8
+ ;b=0
 	rl  b
-	add a,a
+	add a,a			;y*16 (width of screen)
 	rl  b
-	srl d
-	srl d
-	srl d
-	add a,d
-	jr  nc,_n1
-	inc b
-_n1:	ld  c,a
-	add hl,bc
+	srl d			;d/2
+	srl d			;d/4
+	srl d			;d/8 (8 bits in byte) ** c is set when overflow
+	add a,d			;a = (Y*16+X/8) mod 256
+	jr  nc,_n1		;jump if no carry = no overflow = a<=255
+	inc b			;a>255 so increase bc by 256
+_n1:	ld  c,a			;c = (Y*16+X/8) mod 256
+	add hl,bc		;bc = Y*16+X/8
+		;optimize tip: reverse hl <-> bc (??)
           
 	ld  d,(ix)
 	ld  b,(ix+1)
@@ -773,12 +862,13 @@ _iloop:	sla c			;Test leftmost pixel
 	or  (hl)
 	ld  (hl),a
 	ld  a,e
-_noplot: rrca
+_noplot:rrca
 	jr  nc,_notedge		;Test if edge of byte reached
 	inc hl			;Go to next byte
-_notedge:djnz _iloop
+_notedge:
+	djnz _iloop
 	pop hl			;Restore address
-	ld  bc,12		;Go to next line
+	ld  bc,16		;Go to next line
 	add hl,bc
 	pop bc			;Restore data
 	djnz _oloop
@@ -787,53 +877,47 @@ _notedge:djnz _iloop
 ;---------------------- random ------------------------------------------------
 
 Random: 	       ; Creates a random number 0 <= x < A
- push bc
- push de
- push hl
- ld b,a
- ld a,r
- add a,a
- ld hl,0
- ld d,0
- ld e,a
+	push bc
+	push de
+	push hl
+	ld   b,a
+	ld   a,r
+	add  a,a
+	ld   hl,0
+	ld   d,0
+	ld   e,a
 RMul:
- add hl,de
- djnz RMul
- ld a,h
- pop hl
- pop de
- pop bc
- ret
+	add  hl,de
+	djnz RMul
+	ld   a,h
+	pop  hl
+	pop  de
+	pop  bc
+	ret
 
-;------------------------
+;---------------------- display 5digit number ---------------------------------
 
 _D_HL_DECI:
-         push     bc
-         ld       de,up_data+4
-         ld       b,5
-ldhld:   call     UNPACK_HL
-         add      a,'0'
-         ld       (de),a
-         dec      de
-         djnz     ldhld
-         ld       hl,up_data
-         ld       b,4
-lis:     ld       a,(hl)
-         cp       '0'
-         jr       nz,dis
-         ld       (hl),' '
-         inc      hl
-         djnz     lis
-dis:     ld       hl,up_data
-         call     _puts
-         pop      bc
-         ret
-
-up_data: .db      "PAD98",0
+	push bc			;save bc
+	ld   de,savestr+4	;savenr saves number string
+	ld   b,5		;five digits
+ldhld:	call UNPACK_HL		;one digit of hl
+	add  a,'0'		;make number
+	ld   (de),a		;save into savenr
+	dec  de			;point to next digit
+	djnz ldhld		;repeat for all digits
+dis:	ld   hl,savestr
+	call _vputs
+	pop  bc
+	ret
 
+savestr:
+	.db "PAD98",0
 
 
+;------------------------------------------------------------------------------
 ;------------------------------- sprites --------------------------------------
+;------------------------------------------------------------------------------
 
 spr_ship:
 	.db 9,1		;ship icon
@@ -841,7 +925,7 @@ spr_ship:
 	.db %11111000	; █████
 	.db %00111110	;   █████
 	.db %11111001	; █████  █
-	.db %11111101	; ██████ █
+	.db %11111001	; █████  █
 	.db %11111001	; █████  █
 	.db %00111110	;   █████
 	.db %11111000	; █████
@@ -849,13 +933,13 @@ spr_ship:
 
 spr_ship01:
 	.db 7,7		;ship alpha class
-	.db %01110000	;  ███
+	.db %01111000	;  ████
 	.db %11100000	; ███
 	.db %11111100	; ██████
 	.db %11110010	; ████  █
 	.db %11111100	; ██████
 	.db %11100000	; ███
-	.db %01110000	;  ███
+	.db %01111000	;  ████
 spr_ship02:
 	.db 7,7		;ship beta class
 	.db %11000000	; ██
@@ -868,20 +952,22 @@ spr_ship02:
 
 spr_bullet01:
 	.db 5,3		;your bullets
-	.db %00110000	;   ░▒▓██
-	.db %11111000	; ░▒▓█████
-	.db %00110000	;   ░▒▓██
+	.db %00110000	;   ░▒▓█▒
+	.db %11111000	; ░▒▓████▒
+	.db %00110000	;   ░▒▓█▒
 spr_bullet02:
 	.db 5,3		;your bullets
-	.db %11110000	; ░▒▓████
-	.db %11111000	; ░▒▓█████
-	.db %11110000	; ░▒▓████
+	.db %11110000	; ░▒▓███▒
+	.db %11111000	; ░▒▓████▒
+	.db %11110000	; ░▒▓███▒
 
 spr_bullet11:
 	.db 3,3		;enemy bullets
-	.db %01000000	;  █▓▒░
-	.db %11100000	; ███▓▒░
-	.db %01000000	;  █▓▒░
+	.db %01000000	;  ▒▓▒░
+	.db %11100000	; ▒██▓▒░
+	.db %01000000	;  ▒▓▒░
+
+;---------------------------------------- explosion -------------------------------------------
 
 spr_explosion:                               
 	.db 8,6		;1
@@ -948,39 +1034,63 @@ spr_explosion:
 	.db %00000010	;       █▒
 	.db %00100100	;   █▒ █
 
+;--------------------------------------- bar -----------------------------------
+
+spr_icon00:
+	.db 8,7
+	.db %10101010	; █ █ █ █
+	.db %11010101	; ██ █ █ █
+	.db %10101010	; █ █ █ █
+	.db %11010101	; ██ █ █ █
+	.db %10101010	; █ █ █ █
+	.db %11010101	; ██ █ █ █
+	.db %10101010	; █ █ █ █
 spr_icon01:
-	.db 5,4
-	.db %00100000	;   █
-	.db %10101000	; █ █ █
-	.db %11111000	; █████
-	.db %01110000	;  ███
+	.db 8,7
+	.db %10000000	; █.......
+	.db %10000000	; █
+	.db %10000000	; █
+	.db %10000000	; █
+	.db %10000000	; █
+	.db %10000000	; █
+	.db %10000000	; █
 spr_icon02:
-	.db 5,4
-	.db %00000000	;  ███
-	.db %00000000	; ██ ██
-	.db %00000000	; █   █
-	.db %00000000	;
+	.db 8,7
+	.db %10000000	; █
+	.db %10000000	; █
+	.db %10000000	; █
+	.db %10000000	; █
+	.db %10000000	; █
+	.db %10000000	; █
+	.db %10000000	; █
 
 ;---------------------------- texts -------------------------------------------
 
-txt_title:	.db "* * NEMESIS * *",0
+txt_about:	.db "v0.6.820 ","by Shiar  "
+		.db "(ICQ#43840958)",0
+txt_1player:	.db "1 PLAYER",0
+txt_2players:	.db "2 PLAYERS",0
 txt_level:	.db "LEVEL ",0
 txt_gameover:	.db "GAME OVER!",0
-txt_score:	.db "SCORE",0
+txt_lives:	.db "Lx0?",0
 
 ;---------------------------- save data ---------------------------------------
 
 stored_data_start:
 
-level		.db $00			;level number
 timer		.db $00			;frame counter
-curevent	.dw Leveldata+1		;next event
-nextevent	.db (Leveldata)		;time to next event
+level		.db $00			;level number
+levelp		.dw level01		;pointer to level data
+
+eventenemy	.db $02			;enemy type
+eventtime	.db $15			;enemy frequency
+eventleft	.db $00			;nr. of enemies still to come
+nextevent	.db $50			;time to next event
 
 score		.dw $0000
 
 your_occ	.db $00			;0=normal 1..16=exploding
-;lives		.dw $0003	;unused
+lives		.dw $0003	;unused
 x		.db $16			;x-pos
 y		.db $46			;think about it..
 hp		.db $00			;hitpoints left
@@ -988,7 +1098,7 @@ hp		.db $00			;hitpoints left
 ybullets	.dw 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0	;10 x (state,x,y)
 ebullets	.dw 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0	;10 x (state,x,y)
 
-nrenemies	= 32
+nrenemies	= 20
 enemies		.dw $0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000
 		.dw $0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000
 		.dw $0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000
@@ -1000,11 +1110,16 @@ enemies		.dw $0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000
 		.dw $0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000
 
 ; %111111 (HP left) 11 (00=no enemy 01=exploding 10=normal 11=moving)
-; %111 (move ptrn) 11111 (ship or explosion frame)  %11111111 (x) %11111111 (y)
-
+; %11111111 (ship type or explosion frame)  %11111111 (x) %11111111 (y)
 
 ;---------------------------- enemy data --------------------------------------
 
+sprites:
+	.db $00
+	.db spr_enemy02-spr_enemy01
+	.db spr_enemy03-spr_enemy01
+	.db spr_enemy04-spr_enemy01
+
 spr_enemy01:
 	.db 6,6		;enemy type one
 	.db %00111100	;   ████
@@ -1014,13 +1129,14 @@ spr_enemy01:
 	.db %01110000	;  ███
 	.db %00111100	;   ████
 spr_enemy02:
-	.db 6,6		;enemy type two
-	.db %00111000	;   ███
-	.db %01100000	;  ██
+	.db 8,7		;enemy type two
+	.db %00111111	;    █████
+	.db %01111000	;  ████
 	.db %11111100	; ██████
+	.db %11111110	; ███████
 	.db %11111100	; ██████
-	.db %01100000	;  ██
-	.db %00111000	;   ███
+	.db %01111000	;  ████
+	.db %00111111	;    █████
 spr_enemy03:
 	.db 6,6		;enemy type three
 	.db %01111100	;  █████
@@ -1037,106 +1153,85 @@ spr_enemy04:
 	.db %11111000	; █████
 	.db %01111100	;  █████
 	.db %00111000	;   ███
+spr_enemy05:
+	.db 7,6		;enemy type four
+	.db %00011110	;    ████
+	.db %01111110	;  ██████
+	.db %11111100	; ██████
+	.db %11111100	; ██████
+	.db %01111110	;  ██████
+	.db %00011110	;    ████
 
 enemy01:				;HP:1  move:- fire:-
-	.db %00000010,%00000000,%00000000		;first two enemy bytes
+	.db %00000010,%00000000			;first two enemy bytes
 enemy02:				;HP:1  move:1 fire:1.5%
-	.db %00000011,%00100001,%01111111
+	.db %00000010,%00000001
 enemy03:				;HP:2  move:- fire:3%
-	.db %00000110,%00000010,%00001111
+	.db %00000110,%00000010
 enemy04:				;HP:5  move:- fire:6%
-	.db %00010010,%00000011,%00000011
+	.db %00010010,%00000011
 enemy05:				;HP:10 move:- fire:25%
-	.db %00100111,%00000100,%00000011
-
-;---------------------------- level data --------------------------------------
-
-Leveldata:			;time,enemyclass,ypos
-	.db $0d,$00,$38			;first wave (bottom)
-	.db $00,$00,$40
-	.db $00,$00,$48
-	.db $1e,$00,$10			;second wave (top)
-	.db $00,$00,$18
-	.db $00,$00,$20
-	.db $1e,$00,$24			;third wave (middle)
-	.db $00,$02,$2c
-	.db $00,$00,$34
-
-	.db $0d,$00,$10			;top & bottom
-	.db $00,$00,$4a
-	.db $2a,$01,$2d			;middle: moving
-	.db $0c,$02,$2d			;	 3HP
-	.db $0b,$02,$2d			;	 3HP
-	.db $09,$00,$27			;two 1HP behind him
-	.db $00,$00,$33
-	.db $09,$02,$21			;two 3HP behind them
-	.db $00,$02,$39
-	.db $09,$02,$1b			;and two 3HP behind them
-	.db $00,$02,$3f
-
-	.db $15,$03,$11			;one vertical line of 8HPs
-	.db $00,$03,$19
-	.db $00,$03,$21
-	.db $00,$03,$29
-	.db $00,$03,$31
-	.db $00,$03,$39
-	.db $00,$03,$41
-	.db $00,$03,$49
-
-	.db $0c,$02,$11			;one vertical line of 3HPs
-	.db $00,$02,$19
-	.db $00,$02,$21
-	.db $00,$02,$29
-	.db $00,$02,$31
-	.db $00,$02,$39
-	.db $00,$02,$41
-	.db $00,$02,$49
-
-	.db $0c,$00,$11			;one vertical line of 1HPs
-	.db $00,$00,$19
-	.db $00,$00,$21
-	.db $00,$00,$29
-	.db $00,$00,$31
-	.db $00,$00,$39
-	.db $00,$00,$41
-	.db $00,$00,$49
-
-
-
-
-
-
-
-	.db $f1,$01,$40
-	.db $10,$00,$30
-	.db $10,$02,$20
-	.db $40,$01,$10
-	.db $01,$00,$44
-	.db $15,$01,$31
-	.db $04,$02,$38
-	.db $05,$00,$40
-	.db $03,$00,$2f
-	.db $04,$00,$3a
-	.db $12,$02,$10
-	.db $10,$03,$18
-	.db $0e,$03,$20
-	.db $0c,$03,$28
-	.db $0a,$02,$30
-	.db $08,$02,$38
-	.db $06,$01,$40
-	.db $04,$00,$48
-	.db $2a,$00,$20
-	.db $ff,$ff,$ff
+	.db %00100111,%00000100
+
+;----------------------------- level info -------------------------------------
+
+level01:
+	.db $00,$15,$30			;enemy nr ; enemy frequency ; next lvl
+level02:
+	.db $01,$11,$4c
+level03:
+	.db $02,$19,$40
+level04:
+	.db $03,$0f,$50
+level05:
+	.db $04,$2e,$3e
+
+;----------------------------- logo -------------------------------------------
+
+logo_nemesis:
+.db %11111111,%11111111,%11111111,%11111110,%11111111,%11110111,%11111111,%11111110,%11111111,%111101111,%11111111,%00001011,%11111111,%11111111,%11111111,%11111000
+.db %01111111,%11111111,%11111111,%11111110,%11111111,%11110111,%11111111,%11111110,%11111111,%111101111,%11111111,%00011011,%11111111,%11111111,%11111111,%11110000
+.db %00111111,%11111111,%11111111,%11111110,%11111111,%11110111,%11111111,%11111110,%11111111,%111101111,%11111111,%00111011,%11111111,%11111111,%11111111,%11100000
+.db %00011111,%11111111,%11111111,%11111110,%11111111,%11110111,%11111111,%11111110,%11111111,%111101111,%11111111,%01111011,%11111111,%11111111,%11111111,%11000000
+.db %00000000,%00000000,%00000001,%00011110,%00010000,%00000000,%10000001,%00011110,%00010000,%000000001,%00000000,%00001000,%01000000,%00000000,%00000000,%00000000
+.db %00000000,%00000000,%00000011,%00011110,%00110000,%00000001,%10000011,%00011110,%00110000,%000000011,%00000000,%00011000,%11000000,%00000000,%00000000,%00000000
+.db %00000000,%00000000,%00000111,%00011110,%01110000,%00000011,%10000111,%00011110,%01110000,%000000111,%00000000,%00111001,%11000000,%00000000,%00000000,%00000000
+.db %00000000,%00000000,%00001111,%00011110,%11111111,%00000111,%10001111,%00011110,%11111111,%000001111,%11111111,%01111011,%11111111,%11000000,%00000000,%00000000
+.db %00000000,%00000000,%00001111,%00011110,%11111111,%00000111,%10001111,%00011110,%11111111,%000001111,%11111111,%01111011,%11111111,%11000000,%00000000,%00000000
+.db %00000000,%00000000,%00001111,%00011110,%11111111,%00000111,%10001111,%00011110,%11111111,%000001111,%11111111,%01111011,%11111111,%11000000,%00000000,%00000000
+.db %00000000,%00000000,%00001111,%00011110,%11111111,%00000111,%10001111,%00011110,%11111111,%000001111,%11111111,%01111011,%11111111,%11000000,%00000000,%00000000
+.db %00000000,%00000000,%00001111,%00011110,%11110000,%00000111,%10001111,%00011110,%11110000,%000000000,%00001111,%01111000,%00000011,%11000000,%00000000,%00000000
+.db %00000000,%00000000,%00001111,%00011110,%11110000,%00000111,%10001111,%00011110,%11110000,%000000000,%00001111,%01111000,%00000011,%11000000,%00000000,%00000000
+.db %00000000,%00000000,%00001111,%00011110,%11110000,%00000111,%10001111,%00011110,%11110000,%000000000,%00001111,%01111000,%00000011,%11000000,%00000000,%00000000
+.db %00000000,%00000000,%00001111,%00011110,%11110000,%00000111,%10001111,%00011110,%11110000,%000000000,%00001111,%01111000,%00000011,%11000000,%00000000,%00000000
+.db %00000000,%00000000,%00001111,%00011110,%11111111,%11110111,%10001111,%00011110,%11111111,%111101111,%11111111,%01111011,%11111111,%11000000,%00000111,%11010001
+.db %00000000,%00000000,%00001111,%00011110,%11111111,%11110111,%10001111,%00011110,%11111111,%111101111,%11111111,%01111011,%11111111,%11000000,%00000001,%00011011
+.db %00000000,%00000000,%00001111,%00011110,%11111111,%11110111,%10001111,%00011110,%11111111,%111101111,%11111111,%01111011,%11111111,%11000000,%00000001,%00010101
+.db %00000000,%00000000,%00001111,%00011110,%11111111,%11110111,%10001111,%00011110,%11111111,%111101111,%11111111,%01111011,%11111111,%11000000,%00000001,%00010001
 
 ;----------------------------- end --------------------------------------------
 
 	.end
 .end
 
+;----------------------------- NEMESIS'86 by Shiar ----------------------------
 
+;Game · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · NEMESIS
+;Version  · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 0.6.820
+;Latest modification  · · · · · · · · · · · · · · · · · · · · · · · · 20.IIX.99
+;Calc · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ·  TI-86 only
+;Size · · · · · · · · · · · · · · · · · · · · · · · · · · ·  2077 bytes on calc
 
+;Author · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · SHIAR
+;ICQ · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ·  #43840958
+;E-mail · · · · · · · · · · · · · · · · · · · · · · · · · ·  shiar@wishmail.net
+;Homepage · · · · · · · · · · · · · · · · · · coming soon (www.wish.net/~shiar)
 
-;----------------------------- NEMESIS'86 by Shiar ----------------------------
+;Beta:  yes · ·  still to come: lives, armor, powerups, more levels, enemies...
+;Sound:  no · · · · · · · · · · · · don't know if i'll make sounds... we'll see
+;Fun:   yes · · · · · although not yet finished, the game is playable: 5 levels
+;Bugs:  yes  crashes after death; press <EXIT> at GameOver-screen. Send me more
+;Source: no · · · · · · · ·  not yet, will be released when Nemesis is finished
 
 ;----------------------------- version history --------------------------------
 
@@ -1171,7 +1266,7 @@ Leveldata:			;time,enemyclass,ypos
 ;	+ shell-icon added (YAS type)
 ;	* code optimizations, some data "compression"
 ;	* explosion looks better, and some vars removed/smaller
-;	# enemies are removed if at left side (instead of becoming invisible)
+;	# enemies are removed when at left side (instead of becoming invisible)
 ;	+ displays level number before each level begins
 ;
 ; 0.5.725 -- 25.VII.99 -- size 1778
@@ -1185,5 +1280,21 @@ Leveldata:			;time,enemyclass,ypos
 ;	* game over screen will be displayed just *after* your ship's gone
 ;	+ frame counter onscreen
 ;
+; 0.6.820 -- 20.IIX.99 -- size 2152 (2077 on calc)
+;
+;	* play field increased to full screen instead of 3/4
+;	+ bottom eight lines used for score (etc) display
+;	- no more solid levels, enemies are placed at random
+;	+ enemies appear every x turns (depends on level)
+;	# fixed bullets so they don't disappear at 3/4 of the screen
+;	* A LOT of optimizations both in speed and size!!
+;	+ enemy type, frequency, and number specified per level
+;	+ bottom score bar displays score, lives and icons (to be used later)
+;	* smarter enemy handling (so enemies have different sizes)
+;	+ bottom bar divided from playing field by a horizontal line
+;	+ five levels (and five enemies) made
+;	# game vars reset at start and game over
+;	+ NEMESIS LOGO displayed at startup!! (also, program grew 350bytes ):
+;	+ version/credits string displayed below logo: v0.6.820 by shiar (ICQ#)
 
 ;	 + added	- removed	* changed	# bug fixed