From: Mischa Poslawsky <nemesis@shiar.org>
Date: Mon, 19 Jul 1999 22:00:00 +0000 (+0200)
Subject: version 0.4: misc code improvements
X-Git-Url: http://git.shiar.net/nemesis.git/commitdiff_plain/026d2d55516b9bf4d2826305f33a898043e46b81

version 0.4: misc code improvements

# collision detection fixed and optimized (much faster now!)
+ shell-icon added (YAS type)
* code optimizations, some data "compression"
* explosion looks better, and some vars removed/smaller
# enemies are removed when @ left side (instead of becoming invisible)
+ displays level number before each level begins
---

diff --git a/nemesis.z80 b/nemesis.z80
index b735b9c..19d3b9e 100644
--- a/nemesis.z80
+++ b/nemesis.z80
@@ -6,9 +6,10 @@
 
 	nop
 	jp  Start
-	.dw $0000
+	.dw $0001
 	.dw Title
-Title:	.db "Nemesis v0.3.719 by Shiar",0
+	.dw spr_ship
+Title:	.db "Nemesis v0.4.720 by Shiar",0
 Start:
 	jr init
 
@@ -22,6 +23,7 @@ init:
 
 ;-------------------- main menu -----------------------------------------------
 
+	call Next_level
 	jp play_game
 
 ;-------------------- exit ----------------------------------------------------
@@ -32,32 +34,15 @@ exit_game:
 ;----------------------- game setup -------------------------------------------
 
 play_game:
-	ld  hl,stored_data_start
-	ld  bc,variables_end-stored_data_start-1
 
 ;---------------------- display setup ----------------------------------------
 
 set_up_display:
 	call _clrLCD
-
-	ld  hl,in_game_text
-	ld  b,3
-l11:	ld  a,(hl)
-	ld  (_curCol),a
-	inc hl
-	ld  a,(hl)
-	ld  (_curRow),a
-	inc hl
+	ld  (_curCol),16
+	ld  (_curRow),6
+	ld  hl,txt_score
 	call _puts
-	djnz l11
-
-in_game_text:
-	.db 16,0,"LIVES",0
-	.db 16,3,"LEVEL",0
-	.db 16,6,"SCORE",0
-
-str_question:
-	.db "-----",0
 
 ;------------------------------------------------------------------------------
 ;-------------------------- game loop -----------------------------------------
@@ -71,7 +56,6 @@ Clear_screen:
 	xor a
 	ld  hl,GRAPH_MEM+(16*12)
 	ld  b,a
- ld a,(background)
 clearloop:
 	ld  (hl),a
 	inc hl
@@ -122,9 +106,9 @@ displayloop:
 	dec a
 	jr  nz,displayloop
 
-;	ld  hl,$1007		;Display Score
-;	ld  (_curRow),hl
-;	ld  hl,(score)
+	ld  hl,$1006		;Display Score
+	ld  (_curRow),hl
+	ld  hl,(timer)
 ;	jp  _D_HL_DECI
 	ret
 
@@ -184,7 +168,7 @@ no_right:
 	cp  15			;y > 15
 	jr  z,no_up
 	ld  (hl),a
-no_up:	ld  ix,spr_ship
+no_up:	ld  ix,spr_ship01
 
 display_common:
 	ld  e,(hl)
@@ -214,8 +198,6 @@ explosion_stuff:
 	jr  display_common
 
 damage_you:
-	or  %10101010
-	ld  (background),a
 	ret
 
 ;------------------------- fire bullet ----------------------------------------
@@ -309,8 +291,8 @@ hit_enemies:			;Hits with normal enemies
 	push hl
 
 	ld  a,(hl)
-	and %00000001
-	jr  z,nohit		;no hit when enemy_occ <> 1
+	and %00000010
+	jr  z,nohit		;no hit when enemy_occ <> 2/3
 
 	inc hl
 	inc hl
@@ -339,20 +321,19 @@ hit_enemies:			;Hits with normal enemies
 	dec hl
 	dec hl
 	ld  a,(hl)		;occ
+	ld  b,a
 	srl a
 	srl a			;occ/4 = HP left
 	jr  nz,hpleft
-	ld  (hl),2		;set to explode
+	ld  (hl),$01		;set to explode
 	inc hl
 	ld  (hl),a		;explosionFrame 0
 	pop hl
 	ret
 
 hpleft:
-	dec a
-	add a,a
-	add a,a	
-	inc a			;HP*4+1 = occ 1
+	ld  a,b
+	sub %00000100		;decrease HP by one
 	ld  (hl),a		;save
 	pop hl
 	ret
@@ -383,26 +364,25 @@ chk_noenemy:
 	inc de
 	inc de
 	ld  a,(de)
-	or  a
+	or  a			;0 = no enemy present
 	jr  nz,chk_noenemy
 
-	inc de
-	ld  a,(hl)
-	ld  (de),a		;type
+	ld  a,(hl)		;type
 	ld  hl,enemy01
 	ld  c,a
 	ld  b,0
 	add hl,bc
-	add hl,bc
 	add hl,bc		;hl = enemy specs
-	dec de
-	ld  a,(hl)		;load hitpoints
-	or  1			;set type 1 (normal) enemy
+	ld  a,(hl)		;load hitpoints+occ of this enemy class
 	ld  (de),a		;occ
 
+	inc hl
 	inc de
+	ld  a,(hl)		;load movement+type of this enemy class
+	ld  (de),a		;type
+
 	inc de
-	ld  a,$5a
+	ld  a,$5a		;appear at right edge of screen
 	ld  (de),a		;x
 	inc de
 
@@ -411,14 +391,14 @@ chk_noenemy:
 	ld  a,(hl)
 	ld  (de),a		;y
 
-	inc hl			;+0
+	inc hl			;@ next event
 	ld  a,(hl)
-	cp  $ff
+	cp  $ff			;255 = end marker
 	jp  z,Next_level
-	ld  (nextevent),a
+	ld  (nextevent),a	;else time to next event
 
 	inc hl
-	ld  (curevent),hl
+	ld  (curevent),hl	;update pointer
 	ret
 
 ;--------------------------- enemy fires --------------------------------------
@@ -448,8 +428,8 @@ Enemy_fires:
 	dec c			;c = x-2
 	inc hl
 	ld  a,(hl)		;y-pos
-	add a,5
-	ld  e,a			;e = y+5
+	inc a
+	ld  e,a			;e = y+1
 
 	ld  b,10
 	ld  hl,ebullets
@@ -540,7 +520,7 @@ remove_ebullet:
 
 Handle_enemies:
 	ld  hl,enemies
-	ld  b,20
+	ld  b,20		;loop 20x
 
 handle_enemy:
 	push bc
@@ -549,31 +529,38 @@ handle_enemy:
 	ld  a,(hl)
 	and %00000011
 	jr  z,next_enemy	;occ "no enemy" 0
-	and %00000001
-	jr  z,exploding_enemy	;occ "exploding" 2
+	dec a
+	jr  z,exploding_enemy	;occ "exploding" 1
+	ld  b,0
+	dec a
+	jr  z,normal_enemy	;occ "normal" 2
 
-normal_enemy:			;occ "normal" 1
+moving_enemy:			;occ "moving" 3
+	ld  b,1
+
+normal_enemy:
 	inc hl
 	ld  a,(hl)		;type
 	add a,a
 	add a,a
 	add a,a
 	ld  c,a			;type*8 = offset
-	inc hl
-	ld  d,(hl)		;x
-	inc hl
-	ld  e,(hl)		;y
 
-	ld  a,d
-	or  a
-	jr  z,next_enemy
-	dec a
+	inc hl
+	ld  a,(hl)		;x
+	dec a			;move left
+	jp  m,remove_enemy	;off screen
+	jr  z,remove_enemy	;"
 	ld  d,a
-	jr  z,remove_enemy
 
-	ld  (hl),e
+	inc hl
+	ld  a,(hl)		;y
+	;;;;;;;;;;;;;;;;	;
+	ld  (hl),a		;store new y
+	ld  e,a
+
 	dec hl
-	ld  (hl),d
+	ld  (hl),d		;store new x
 	ld  ix,spr_enemy01
 	ld  b,$00
 	add ix,bc
@@ -581,12 +568,9 @@ normal_enemy:			;occ "normal" 1
 	jr  next_enemy
 
 remove_enemy:
-	dec hl
-	dec hl
-enemy_gone:
-	dec hl
+	pop hl
 	ld  (hl),$0000		;bye bye enemy
-
+	push hl
 next_enemy:
 	pop hl
 	ld  bc,$0004
@@ -604,7 +588,7 @@ exploding_enemy:
 
 	ld  a,(hl)
 	cp  15
-	jr  z,enemy_gone	;remove when at last frame
+	jr  z,remove_enemy	;remove when at last frame
 	inc a
 	ld  (hl),a		;next frame
 	jr  next_enemy
@@ -613,55 +597,85 @@ exploding_enemy:
 
 Enemies_hit:
 	ld  a,(your_occ)
-	or  a
+	or  a			;0 = you're normal
 	ret nz
 
 	ld  de,(x)		;e = X, d = Y
-	ld  hl,enemies-4
-check_next:
-	ld  bc,$0004
-	add hl,bc
-
-	ld  a,(hl)
-	cp  $ff
-	ret z			;-1 = no more enemies
+	ld  hl,enemies
+	ld  b,20		;check all 20 enemies
+check_collision:
 	push hl
-	cp  1
-	jr  nz,nocrash		;1 = enemy
+	ld  a,(hl)
+	and %00000010
+	jr  z,check_next	;2/3 = ok
 
 	inc hl
 	inc hl
 	ld  a,(hl)		;check x match
 	sub e
 	add a,6
-	jp  m,nocrash
+	jp  m,check_next
 	cp  12
-	jr  nc,nocrash
+	jr  nc,check_next
 
 	inc hl
 	ld  a,(hl)		;check y match
 	sub d
 	add a,6
-	jp  m,nocrash
+	jp  m,check_next
 	cp  12
-	jr  nc,nocrash
+	jr  nc,check_next
 
 	dec hl
 	dec hl
-	ld  (hl),0		;explosionFrame 0
+	xor a
+	ld  (hl),a		;explosionFrame 0
 	dec hl
-	ld  (hl),2		;set to explode
-	call damage_you
+	inc a
+	ld  (hl),a		;set to explode
+	call damage_you		;auch!
 
-nocrash:
+check_next:
 	pop hl
-	jr  check_next
+	inc hl
+	inc hl
+	inc hl
+	inc hl
+	djnz check_collision
+	ret
 
 ;--------------------------- next level ---------------------------------------
 
 Next_level:
-	ld  hl,Leveldata+1
+	ld  hl,Leveldata+1	;reset level data
 	ld  (curevent),hl
+
+	call _clrLCD		;clear screen
+	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
+
+	call UNPACK_HL
+	add a,'0'
+	ld  b,a
+	call UNPACK_HL
+	add a,'0'
+	call _putc		;display second digit
+	ld  a,b
+	call _putc		;display first digit
+
+	ld  b,$20
+wait:	halt \ halt
+	djnz wait		;delay
+	call _getkey		;wait for keypress
+
 	ret
 
 ;--------------------------- putsprite ----------------------------------------
@@ -752,7 +766,17 @@ up_data: .db      "PAD98",0
 ;------------------------------- sprites --------------------------------------
 
 spr_ship:
-	.db 7,7		;your ship:
+	.db 7,1		;ship icon
+	.db %11000000	; ██
+	.db %11110000	; ████
+	.db %01111100	;  █████
+	.db %01110010	;  ███  █
+	.db %01111100	;  █████
+	.db %11110000	; ████
+	.db %11000000	; ██
+
+spr_ship01:
+	.db 7,7		;ship alpha class
 	.db %01110000	;  ███
 	.db %11100000	; ███
 	.db %11111100	; ██████
@@ -760,6 +784,15 @@ spr_ship:
 	.db %11111100	; ██████
 	.db %11100000	; ███
 	.db %01110000	;  ███
+spr_ship02:
+	.db 7,7		;ship beta class
+	.db %11000000	; ██
+	.db %11110000	; ████
+	.db %01111100	;  █████
+	.db %01110010	;  ███  █
+	.db %01111100	;  █████
+	.db %11110000	; ████
+	.db %11000000	; ██
 
 spr_bullet01:
 	.db 5,3		;your bullets
@@ -778,146 +811,96 @@ spr_bullet11:
 	.db %11100000	; ███▓▒░
 	.db %01000000	;  █▓▒░
 
-spr_enemy01:
-	.db 6,6		;enemy type one
-	.db %00111100	;   ████
-	.db %01110000	;  ███
-	.db %11110000	; ████
-	.db %11110000	; ████
-	.db %01110000	;  ███
-	.db %00111100	;   ████
-spr_enemy02:
-	.db 6,6		;enemy type two
-	.db %01111100	;  █████
-	.db %11110000	; ████
-	.db %10111000	; █ ███
-	.db %10111000	; █ ███
-	.db %11110000	; ████
-	.db %01111100	;  █████
-spr_enemy03:
-	.db 6,6		;enemy type three
-	.db %00111000	;   ███
-	.db %01111100	;  █████
-	.db %11111000	; █████
-	.db %11111000	; █████
-	.db %01111100	;  █████
-	.db %00111000	;   ███
-spr_enemy03:
-	.db 6,6		;enemy type three
-	.db %00111000	; ███
-	.db %01111100	;   ██
-	.db %11111000	; █████
-	.db %11111000	; █████
-	.db %01111100	;  █████
-	.db %00111000	; ███
-
 spr_explosion:                               
 	.db 8,6		;1
 	.db %00000000
-	.db %00011100
-	.db %00111110
-	.db %01010110
-	.db %00111000
+	.db %00011100	;    ███
+	.db %00111110	;   █████
+	.db %01010110	;  █ █ ██
+	.db %00111000	;   ███
 	.db %00000000
 
 	.db 8,6		;2
-	.db %00110000
-	.db %01001110
-	.db %10111110
-	.db %01001111
-	.db %00111000
-	.db %00011010
+	.db %00110000	;   ██
+	.db %01001110	;  █ ▒███
+	.db %10111110	; █ █████
+	.db %01001111	;  █ ▒████
+	.db %00111000	;   ███
+	.db %00011010	;    ██ █
 
 	.db 8,6		;3
-	.db %11110011
-	.db %01001110
-	.db %10110101
-	.db %01000101
-	.db %00111110
-	.db %11011010
+	.db %10110011	; █ ██  ██
+	.db %01001110	;  █  ███
+	.db %10110101	; █ ██▒█▒█
+	.db %01000101	;  █  ▒█▒█
+	.db %00111110	;   █████
+	.db %11011010	; ██ ██ █
 
 	.db 8,6		;4
-	.db %11110010
-	.db %01001110
-	.db %10110101
-	.db %01000101
-	.db %00111110
-	.db %01011010
+	.db %00101010	; ▒ █▒█ █▒
+	.db %01000110	;  █  ▒██
+	.db %10110101	; █ ██ █ █
+	.db %01100110	;  ██  ██▒
+	.db %00111100	;   ████▒
+	.db %01011001	; ▒█ ██ ▒█
 
 	.db 8,6		;5
-	.db %01000001
-	.db %00100110
-	.db %00010101
-	.db %01000100
-	.db %00010010
-	.db %10011010
+	.db %01000001	;  █▒ ▒ ▒█
+	.db %00100101	;  ▒█  █▒█
+	.db %00010100	; ▒ ▒█ █ ▒
+	.db %01000100	;  █▒  █
+	.db %00010010	;   ▒█▒▒█
+	.db %10011010	; █▒ ██ █▒
 
 	.db 8,6		;6
-	.db %01000100
-	.db %00100000
-	.db %00000001
-	.db %01000100
-	.db %00100010
-	.db %10001000
+	.db %01000100	;  █   █ ▒
+	.db %00100000	;   ▒█ ▒ ▒
+	.db %00000001	;    ▒ ▒ █
+	.db %01000100	;  █   █
+	.db %00100010	;   █▒  █
+	.db %01001000	; ▒█ ▒█ ▒
 
 	.db 8,6		;7
-	.db %00001000
-	.db %11000010
-	.db %00000000
-	.db %00100000
-	.db %00000001
-	.db %00110000
+	.db %00001000	;  ▒  █▒
+	.db %11000010	; ██ ▒  █
+	.db %00000000	;        ▒
+	.db %00100000	;  ▒█  ▒
+	.db %00000001	;   ▒   ▒█
+	.db %00110000	;  ▒██▒
 
 	.db 8,6		;8
-	.db %00000100
-	.db %00000000
-	.db %01000000
-	.db %00000000
-	.db %00000001
-	.db %00100100
-
-;---------------------------- enemy types -------------------------------------
-
-enemy01:	.db %00000000,$ff,$ff		;$hits   $fire frequency
-enemy02:	.db %00000100,$ff,$ff
-enemy03:	.db %00001000,$ff,$ff
-
-;---------------------------- level data --------------------------------------
-
-Leveldata:
-	.db $01,$01,$40		;$time (ff=end)    $type    $y-pos
-	.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,$00,$10
-	.db $10,$00,$18
-	.db $0e,$00,$20
-	.db $0c,$00,$28
-	.db $0a,$00,$30
-	.db $08,$00,$38
-	.db $06,$00,$40
-	.db $04,$00,$48
-	.db $2a,$00,$20
-	.db $ff,$ff,$ff
+	.db %00000100	;     ▒█
+	.db %00000000	; ▒▒    ▒
+	.db %01000000	;  █
+	.db %00000000	;   ▒
+	.db %00000010	;       █▒
+	.db %00100100	;   █▒ █
+
+spr_icon01:
+	.db 5,4
+	.db %00100000	;   █
+	.db %10101000	; █ █ █
+	.db %11111000	; █████
+	.db %01110000	;  ███
+spr_icon02:
+	.db 5,4
+	.db %00000000	;  ███
+	.db %00000000	; ██ ██
+	.db %00000000	; █   █
+	.db %00000000	;
 
 ;---------------------------- texts -------------------------------------------
 
-title_message:
-         .db      "* * NEMESIS * *",0
+txt_title:	.db "* * NEMESIS * *",0
+txt_level:	.db "LEVEL ",0
+txt_score:	.db "SCORE",0
 
 ;---------------------------- save data ---------------------------------------
 
 stored_data_start:
 
-level		.dw $0000		;level number
-background	.db %00000001		;level background
-timer		.dw $0000
+level		.db $00			;level number
+timer		.db $00			;frame counter
 curevent	.dw Leveldata+1		;next event
 nextevent	.db (Leveldata)		;time to next event
 
@@ -928,7 +911,6 @@ lives		.dw $0003	;unused
 x		.db $16			;x-pos
 y		.db $46			;think about it..
 hp		.db $00			;hitpoints left
-your_status	.db $00,$00	;unused
 
 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)
@@ -938,21 +920,90 @@ 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
 		.dw $0000,$0000,$0000,$0000,$0000,$0000,$0000,$0000
-; 0011 2233 >>	0=occupation (and %00000011: 0=no enemy 1=normal 2=exploding)
-;		1=frame/ship 2=x 3=y
 
-variables_end:
+; %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)
 
-stored_data_end:
 
+;---------------------------- enemy data --------------------------------------
+
+spr_enemy01:
+	.db 6,6		;enemy type one
+	.db %00111100	;   ████
+	.db %01110000	;  ███
+	.db %11110000	; ████
+	.db %11110000	; ████
+	.db %01110000	;  ███
+	.db %00111100	;   ████
+spr_enemy02:
+	.db 6,6		;enemy type two
+	.db %00111000	;   ███
+	.db %01100000	;  ██
+	.db %11111100	; ██████
+	.db %11111100	; ██████
+	.db %01100000	;  ██
+	.db %00111000	;   ███
+spr_enemy03:
+	.db 6,6		;enemy type three
+	.db %01111100	;  █████
+	.db %11110000	; ████
+	.db %11111000	; █████
+	.db %11111000	; █████
+	.db %11110000	; ████
+	.db %01111100	;  █████
+spr_enemy04:
+	.db 6,6		;enemy type four
+	.db %00111000	;   ███
+	.db %01111100	;  █████
+	.db %11111000	; █████
+	.db %11111000	; █████
+	.db %01111100	;  █████
+	.db %00111000	;   ███
+
+enemy01:
+	.db %00000010,%00000000		;first two enemy bytes
+enemy02:
+	.db %00000010,%00100001
+enemy03:
+	.db %00000110,%00000010
+enemy04:
+	.db %00010010,%00000010
+
+;---------------------------- level data --------------------------------------
+
+Leveldata:
+	.db $01,$01,$40		;$time (ff=end)    $type    $y-pos
+	.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
+
+;----------------------------- end --------------------------------------------
 
 	.end
+.end
 
 
 
 
-;NEMESIS'86 by Shiar
+;----------------------------- NEMESIS'86 by Shiar ----------------------------
 
+;----------------------------- version history --------------------------------
 
 ;0.01.717 -- 17.VII.99 -- size 984
 ;
@@ -978,5 +1029,14 @@ stored_data_end:
 ;	+ some enemies can take multiple hits (differs per class)
 ;	+ all enemies fire bullets at random
 ;	+ if you're hit by bullet/enemy, you'll lose one hitpoint
+;
+; 0.4.720 -- 20.VII.99 -- size 1481
+;
+;	* collision detection fixed and optimized (much faster now!)
+;	+ 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)
+;	+ displays level number before each level begins