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WOLF-LOW.ASM
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;
; WOLF-LOW.VZ MODE(0) version
; WOLF-HI.VZ MODE(1) version
;
; WOLFENSTEIN FPS CODE. by Lawrence Kesteloot. e: lk@teamten.com
; https://github.com/lkesteloot/trs80/tree/master/apps/wolf
; Ported from original TRS80 model 1 to VZ by silly dave.
; Wolf wiki: https://en.wikipedia.org/wiki/Wolfenstein_3D$Development
; Music player by Lyndon Sharp, modified by Shiru.
; Intro tune by Dave
; Menu tune by Shiru
; Slapped together by dave over ~2 or so weeks. Released : 22/9/2024
;
;
; Found src code for trs80 on Lawrence github for the TRS80 Model 1.
; Grabbed it and ran with it.
; Q - forward Z - Show Map (MODE0 game only)
; A - back X - Menu
; M - left C - Credits
; , - right
; s - straffe left
; d - straffe right
;
;
;
;
; ------------------------------------------------------------
;
; c : seems to be working ok. Blue coloured wall.
; D
; E ; with lyndon 1bit music. try.
; H ; intro + music + mode(0) + menu + key + game. TRY.
; I ; Z=MAP
; I2 ; working. current.
;mode0 I3 : column texture 1 and 2
; J : stable mode 0
; j2a : both tunes. 2nd tune needs mode0 in player
; k : intro tune. 2nd tune turned off. 6 mazes (working). inscreen map working. stable.
; k1 : fiddling with postion. no luck
; k2 : second tune on menu - seperate player.
; k3 : 2nd tune working. Fiddling with keys & showmap within 2nd tune playing
; k5 : credits
; k6 : credits
; k74 : stable
; k75 : credit music player
; k84 : seems to be stable. levels 1-0.
;
; To do:
; - initial port done
; - 32x16 operation done
; - intro screen done
; - intro tunes done
; - do map done
; - player positon on map done
; - second tune being on menu done
; - texture sides on walls fail
; - mode 1
; - add credits done
; - music in credits done
;
;
; WALL
; colour
; Number Colour Chr$()
; ------------------------------
; 0 green 143
; 16 yellow 159
; 32 blue 175
; 48 red 191
; 64 buff 207
; 80 cyan 223
; 96 magenta 239
; 112 orange 255
wallcolour equ 64 ; Buff
stride equ 32 ; Break my stride. TRS80=64. VZ=32.
walltexture1 equ 138 + wallcolour
walltexture2 equ 139 + wallcolour
ceilingborder equ 7 ; use 17 for mode(1)
floorborder equ 7 ; use 17 for mode(1)
ceilingtexture equ 223 ; cyan
floortexture equ 255 ; orange
topwalltexture1 equ 130 + wallcolour ; 130
topwalltexture2 equ 131 + wallcolour ; 129
bottomwalltexture1 equ 136+ wallcolour ;
bottomwalltexture2 equ 132+ wallcolour ;
SCREEN_WIDTH equ 32 ; TRS80=64
SCREEN_HEIGHT equ 16 ; NOT USED
MAZE_SIZE equ 8 ; NOT USED
latch equ $6800
video equ $7000
origin equ $8000
videobuffer equ $AB00
org $8000
entry: ld sp, 0
call init
call init_introscreen
menuscr:call init_menuscreen
next_frame:
call get_key_update
call fill_buffer
call draw_screen
jp next_frame
; -------------------------------------------
init:
; -------------------------------------------
ei
call $01c9 ; VZ ROM CLS
ld a, 0 ; MODE(0)
ld ($6800), a
ret
; -------------------------------------------
init_introscreen:
; -------------------------------------------
di
ld a, 8 ; Mode(1)
ld ($6800), a
ld hl, introscreen ; display intro screen
ld de, $7000
ld bc, 2048
ldir
ld hl, intro_music_data ; Play intro music
call playlyndon91
ld a, 0 ; MODE(0)
ld ($6800), a
ei
call $01c9 ; VZ ROM CLS
ret
; -----------------------------------------------------------
init_menuscreen:
; DISPLAY MENU
; PLAY MENU SONG
; PRESS <SPACE>.
; -----------------------------------------------------------
di
ld hl, menu0 ; -ROM String routine stuffs up
ld de, $7000 ;
ld b, 255 ;
msgloop0:ld a, (hl) ; have tried every bloody thing under the sun.
or 64 ; Read string, per each chr$ do an "OR 64", display it.
ld (de), a
inc hl
inc de
djnz msgloop0
ld b, 65+32
msgloop1:ld a, (hl)
or 64
ld (de), a
inc hl
inc de
djnz msgloop1
; jp skip_menu_song2
; Attempt to use the Lydon91 player once for both mode(0) and mode(1)
; Using self modified code. Failed first time. So player is currently in twice for each mode.
; May or may not come back to this if I can be bothered.
;
; ld hl, mask0
; ld (hl), $DD ;mask1 : 28 --> 20 MODE(1) then MODE(0)
; ld hl, mask1
; ld (hl), $21 ;mask1 : 28 --> 20 MODE(1) then MODE(0)
; ld hl, mask2
; ld (hl), $20 ;mask2 : 28 --> 20 MODE(1) then MODE(0)
; ld hl, mask3
; ld (hl), $20 ;mask3 : 28 --> 20 MODE(1) then MODE(0)
; ld hl, mask4
; ld (hl), $20 ;mask4 : 28 --> 20 MODE(1) then MODE(0)
; ld hl, mask5
; ld (hl), $20 ;mask5 : OR A, 28 --> 00 NOP : MODE(1) then MODE(0)
; inc hl
; ld (hl), $20 ;mask5 : OR A, 28 --> 00 NOP : MODE(1) then MODE(0)
;
; ld hl, mask6
; ld (hl), $20 ;mask5 : OR A, 28 --> 00 NOP : MODE(1) then MODE(0)
; inc hl
; ld (hl), $20 ;mask5 : OR A, 28 --> 00 NOP : MODE(1) then MODE(0)
;
; ld hl, mask7
; ld (hl), $20 ;mask5 : OR A, 28 --> 00 NOP : MODE(1) then MODE(0)
; inc hl
; ld (hl), $20 ;mask5 : OR A, 28 --> 00 NOP : MODE(1) then MODE(0)
;skip_menu_song2:
;hereas jp hereas
ld hl, wolf_menu_tune ; play menu/credit tune.
call playlyndon91menu
skip_menu_song:
ret
; -------------------------------------------
; Update model from inputs.
; https://www.trs-80.com/wordpress/zaps-patches-pokes-tips/keyboard-map/
; -------------------------------------------
get_key_update:
; -------------------------------------------
; Read keyboard
; Update position.
; Q - forward
; A - back
; M - left
; , - right
; s - straffe left
; d - straffe right
; x20 x10 x8 x4 x2 x1
; ----------------------------
;68FE R Q E W T
;68FD F A D ctrl S G
;68FB V Z C SHFT X B
;68F7 4 1 3 2 5
;68EF M SPC , . N
;68DF 7 0 8 - 9 6
;68BF U P I RTN O Y
;687F J L K : L H
;
KeyX: ld a, ($68FB) ; KEY: X MENU
and $2
jr nz, not_X
jp menuscr
not_X:
KeyM: ld a, ($68EF) ; KEY: M LEFT
and $20
jr nz, not_m
ld a, (dir)
add a, 1 ; POV turn left, screen goes right.
and 63
ld (dir), a
jp end_keyboard
not_m:
keyComma:ld a, ($68EF) ; KEY: comma RIGHT
and $08
jr nz, not_right
ld a, (dir)
sub 1 ; POV turn right, screen goes left.
and 63
ld (dir), a
jp end_keyboard
not_right:
keyQ: ld a, ($68FE) ; KEY: Q Forwards
and $10
jr nz, not_q
call premove
ld a, (posX)
ld hl, dir
ld l, (hl)
ld h, high (DIR_TABLE_X)
ld h, (hl)
sra h
add a, h
ld (posX), a
ld a, (posY)
ld h, high (DIR_TABLE_Y)
ld h, (hl)
sra h
add a, h
ld (posY), a
call postmove
jp end_keyboard
not_q:
keyA: ld a, ($68FD) ; KEY: A BACKWARDS
and $10
jr nz, not_a
call premove
ld a, (posX)
ld hl, dir
ld l, (hl)
ld h, high (DIR_TABLE_X)
ld h, (hl)
sra h
sub h
ld (posX), a
ld a, (posY)
ld h, high (DIR_TABLE_Y)
ld h, (hl)
sra h
sub h
ld (posY), a
call postmove
jp end_keyboard
not_a:
ld a, ($68fd) ; KEY: S Staffe left
and $02
jr nz, not_s
call premove
ld a, (posX)
ld hl, dir
ld l, (hl)
ld h, high (DIR_TABLE_Y)
ld h, (hl)
sra h
add a, h
ld (posX), a
ld a, (posY)
ld h, high (DIR_TABLE_X)
ld h, (hl)
sra h
sub h
ld (posY), a
call postmove
jp end_keyboard
not_s:
keyD: ld a, ($68fd) ; KEY: D Straffe right
and $08
jr nz, not_d
call premove
ld a, (posX)
ld hl, dir
ld l, (hl)
ld h, high (DIR_TABLE_Y)
ld h, (hl)
sra h
sub h
ld (posX), a
ld a, (posY)
ld h, high (DIR_TABLE_X)
ld h, (hl)
sra h
add a, h
ld (posY), a
call postmove
jp end_keyboard
not_d:
keyZ: ld a, ($68fB) ; KEY: Z SHOW MAP
and $10
jr nz, not_z
ld a, (maponoff)
cp 0
jr z, turnmapon ; map off. turn map on.
cp 1
jr z, turnmapoff ; map on. turn map off.
jr not_z
turnmapon:ld a, 1 ; map was off. turn map on.
ld (maponoff), a
jr turnmap
turnmapoff:ld a, 0 ; map was on. turn map off.
ld (maponoff), a
turnmap:call show_map
not_z: ld a, ($68FB) ; Key : C for credits
and $8
jr nz, not_c
call show_credits ; jump to call if <C> is pressed.
not_c:
end_keyboard:
ret
; ----------------------------------------
; Save the player position so that if we
; run into a wall, we can back off.
premove:ld a, (posX)
ld (savePosX), a
ld a, (posY)
ld (savePosY), a
ret
postmove: ; uint_8 mapX = posX >> 5;
ld a, (posX)
srl a
srl a
srl a
srl a
srl a
ld l, a
ld a, (posY) ; uint_8 mapY = (posY >> 5) << 3;
srl a
srl a
and $38 ; 3 bits
or l ; if (MAZE[mapY][mapX] != ' ')
ld h, high(MAZE)
ld l, a
ld a, (hl)
cp ' '
ret z ; not in wall
ld a, (savePosX) ; In wall, restore old position.
ld (posX), a
ld a, (savePosY)
ld (posY), a
ret
; -------------------------------------------
fill_buffer:
ld hl, BUFFER
ld c, 0
ld b, SCREEN_WIDTH
fill_loop:
call get_height
ld (hl), a
inc hl
inc c
djnz fill_loop
ret
; -------------------------------------------
draw_screen:
ld de, stride ; 64 ; Stride
ld bc, 0 ; Column
hloop: push bc
ld hl, BUFFER ; Load height from buffer.
add hl, bc
ld a, (hl)
bit 7, a ; Test top bit for texture.
jp z, texture_2
texture_1:
ld iyl, walltexture1 ; $80+1+4+16
and $7F
push af
ld h, high(TOP_TEXTURE_1)
ld l, a
ld a, (hl)
ld ixh, a
ld h, high(BOTTOM_TEXTURE_1)
ld a, (hl)
ld ixl, a
pop af
jp end_texture
texture_2:
ld iyl, walltexture2 ; $80+4
and $7F
push af
ld h, high(TOP_TEXTURE_2)
ld l, a
ld a, (hl)
ld ixh, a
ld h, high(BOTTOM_TEXTURE_2)
ld a, (hl)
ld ixl, a
pop af
end_texture:
; See if we're too tall and should
; remove the top/bottom character.
cp 24
jr nz, not_too_tall
push af
ld a, iyl
ld ixh, a
ld ixl, a
pop af
dec a
not_too_tall:
; Divide A by 3.
ld h, high(DIV3)
ld l, a
ld a, (hl)
; Height is now in A.
; Top of column.
ld hl, videobuffer ;video
add hl, bc
; Ceiling.
ld b, ceilingborder
jp toplooptest
toploop:
ld (hl), ceilingtexture ; 143 ;128
add hl, de
dec b
toplooptest:
cp b ; Stop at a
jp nz, toploop
; Border between ceiling and wall.
ld b, ixh
ld (hl), b
add hl, de
; Wall.
ld b, a
sla b
ld c, iyl
jp vlooptest
vloop:
ld (hl), c
add hl, de
dec b
vlooptest:
jp nz, vloop
; Border between wall and floor.
ld b, ixl
ld (hl), b
add hl, de
; Floor.
ld b, floorborder
jp bottomlooptest
bottomloop:
ld (hl), floortexture ; 143 + 16 ;128
add hl, de
dec b
bottomlooptest:
cp b ; Stop at a
jp nz, bottomloop
pop bc
inc bc
ld a, c
; cp 64
cp 32
; cp 16
jp nz, hloop
call show_map
screen_update: ; from video_buffer to video.
di
ld hl, videobuffer
ld de, video
ld bc, 512 ; MODE1 : 2048-784
screen_update_loop1: ; wait for first retrace
ld a, (0x6800)
rla
jr c,screen_update_loop1
ldir ; copy first slice during the retrace
; ld bc, 784 ; mode1: prepare for second slice. wait for second retrace
;screen_update_loop2: ; mode1:
; ld a, (0x6800) ; mode1:
; rla ; mode1:
; jr c,screen_update_loop2 ; mode1:
; ldir ; mode1: ; copy the second slice during the retrace
ret
; -------------------------------------------
; Given 0 <= C <= 63 column, return 0 <= A <= 23 height.
; Set high bit of A to use different texture.
get_height:
push hl
push bc
; int8_t cameraX = 2*x - SCREEN_WIDTH; // x-coordinate in camera space
sla c ; c *= 2
ld a, c
sub SCREEN_WIDTH ; c -= SCREEN_WIDTH
ld (cameraX), a
; int8_t dirX = DIR_TABLE_X[dir];
ld hl, dir
ld l, (hl)
ld h, high(DIR_TABLE_X)
ld a, (hl)
ld (dirX), a
; int8_t planeY = dirX;
ld (planeY), a
; int8_t dirY = DIR_TABLE_Y[dir];
ld h, high(DIR_TABLE_Y)
ld a, (hl)
ld (dirY), a
; int8_t planeX = -dirY;
neg
ld (planeX), a
; int8_t rayDirX = dirX + planeX * cameraX / SCREEN_WIDTH;
ld a, (planeX)
ld h, a
ld a, (cameraX)
ld e, a
call signed_mult_8
; Divide by SCREEN_WIDTH (64) by shifting left and using high byte.
add hl, hl
add hl, hl
ld a, (dirX)
add a, h
ld (rayDirX), a
; int8_t rayDirY = dirY + planeY * cameraX / SCREEN_WIDTH;
ld a, (planeY)
ld h, a
ld a, (cameraX)
ld e, a
call signed_mult_8
; Divide by SCREEN_WIDTH (64) by shifting left and using high byte.
add hl, hl
add hl, hl
ld a, (dirY)
add a, h
ld (rayDirY), a
; // which box of the map we're in
; uint_8 mapX = posX >> 5;
ld a, (posX)
srl a
srl a
srl a
srl a
srl a
ld (mapX), a
; uint_8 mapY = posY >> 5; (pre-shifted 3)
ld a, (posY)
srl a
srl a
and $38
ld (mapY), a
; See if we're aligned with one of the
; axes, in which case we'll get a
; divide-by-zero error. Special case
; both of those.
ld a, (rayDirX)
or a
jp nz, rayDirX_not_zero
; ----------------------------------------
; uint8_t deltaDistY = SIGNED_DIV_TABLE[(uint8_t) rayDirY];
ld h, high(SIGNED_DIV_TABLE)
ld a, (rayDirY)
ld l, a
ld a, (hl)
ld (deltaDistY), a
; if (rayDirY < 0) {
ld a, (rayDirY)
bit 7, a
jr z, rayDirYPos
; stepY = -1;
ld a, -8
ld (stepY), a
; sideDistY = (posY - mapY*32) * deltaDistY / 32;
ld a, (posY)
and $1F ; keep fractional part.
jp rayDirYEnd
rayDirYPos:
; } else {
; stepY = 1;
ld a, 8
ld (stepY), a
; sideDistY = ((mapY + 1)*32 - posY) * deltaDistY / 32;
ld a, (posY)
and $1F ; keep fractional part.
xor $1F ; subtract from 32.
rayDirYEnd:
ld h, a
ld a, (deltaDistY)
ld e, a
call mult8
; /= 32
xor a
add hl, hl
rla
add hl, hl
rla
add hl, hl
rla
ld l, h
ld h, a
ld (sideDistY), hl
; perform DDA
loop:
; sideDistY += deltaDistY;
ld de, (sideDistY)
ld a, (deltaDistY)
ld l, a
ld h, 0
add hl, de
ld (sideDistY), hl
; mapY += stepY;
ld a, (mapY)
ld hl, stepY
add a, (hl)
ld (mapY), a
; Check if ray has hit a wall
; if (MAZE[mapY][mapX] != ' ') hit = 1;
ld a, (mapX)
ld hl, mapY
or (hl)
ld h, high(MAZE)
ld l, a
ld a, (hl)
cp ' '
jp z, loop
; Calculate distance projected on camera direction (Euclidean
; distance would give fisheye effect!)
; perpWallDist = sideDistY - deltaDistY;
ld hl, (sideDistY)
ld a, (deltaDistY)
ld e, a
ld d, 0
or a
sbc hl, de
ld (dist), hl
; rayDirX = 0 -------------------------
ld b, $00 ; Hit Y side.
jp end_special_cases
rayDirX_not_zero:
ld a, (rayDirY)
or a
jp nz, rayDirY_not_zero
; ----------------------------------------
; uint8_t deltaDistX = SIGNED_DIV_TABLE[(uint8_t) rayDirX];
ld h, high(SIGNED_DIV_TABLE)
ld a, (rayDirX)
ld l, a
ld a, (hl)
ld (deltaDistX), a
; calculate step and initial sideDist
; if (rayDirX < 0) {
ld a, (rayDirX)
bit 7, a
jr z, rayDirXPos
; stepX = -1;
ld a, -1
ld (stepX), a
; sideDistX = (posX - mapX*32) * deltaDistX / 32;
ld a, (posX)
and $1F ; keep fractional part.
jp rayDirXEnd
rayDirXPos:
; } else {
; stepX = 1;
ld a, 1
ld (stepX), a
; sideDistX = ((mapX + 1)*32 - posX) * deltaDistX / 32;
ld a, (posX)
and $1F ; keep fractional part.
xor $1F ; subtract from 32.
rayDirXEnd:
ld h, a
ld a, (deltaDistX)
ld e, a
call mult8
; /= 32
xor a
add hl, hl
rla
add hl, hl
rla
add hl, hl
rla
ld l, h
ld h, a
ld (sideDistX), hl
; perform DDA
loop2:
; sideDistX += deltaDistX;
ld hl, (sideDistX)
ld a, (deltaDistX)
ld e, a
ld d, 0
add hl, de
ld (sideDistX), hl
; mapX += stepX;
ld a, (mapX)
ld hl, stepX
add a, (hl)
ld (mapX), a
; Check if ray has hit a wall
; if (MAZE[mapY][mapX] != ' ') hit = 1;
ld a, (mapX)
ld hl, mapY
or (hl)
ld h, high(MAZE)
ld l, a
ld a, (hl)
cp ' '
jp z, loop2
; Calculate distance projected on camera direction (Euclidean
; distance would give fisheye effect!)
; perpWallDist = sideDistX - deltaDistX;
ld hl, (sideDistX)
ld a, (deltaDistX)
ld e, a
ld d, 0
or a
sbc hl, de
ld (dist), hl
; rayDirY = zero -------------------------
ld b, $80 ; Hit X side.
jp end_special_cases
rayDirY_not_zero:
; neither is zero -------------------------
; uint8_t deltaDistX = SIGNED_DIV_TABLE[(uint8_t) rayDirX];
ld h, high(SIGNED_DIV_TABLE)
ld a, (rayDirX)
ld l, a
ld a, (hl)
ld (deltaDistX), a
; uint8_t deltaDistY = SIGNED_DIV_TABLE[(uint8_t) rayDirY];
ld a, (rayDirY)
ld l, a
ld a, (hl)
ld (deltaDistY), a
; calculate step and initial sideDist
; if (rayDirX < 0) {
ld a, (rayDirX)
bit 7, a
jr z, rayDirXPos1
; stepX = -1;
ld ixl, -1
; sideDistX = (posX - mapX*32) * deltaDistX / 32;
ld a, (posX)
and $1F ; keep fractional part
jp rayDirXEnd1
rayDirXPos1:
; } else {
; stepX = 1;
ld ixl, 1
; sideDistX = ((mapX + 1)*32 - posX) * deltaDistX / 32;
ld a, (posX)
and $1F ; keep fractional part
xor $1F ; subtract from 32
rayDirXEnd1:
ld h, a
ld a, (deltaDistX)
ld e, a
call mult8
; /= 32
xor a
add hl, hl
rla
add hl, hl
rla
add hl, hl
rla
ld l, h
ld h, a
ld (sideDistX), hl
; if (rayDirY < 0) {
ld a, (rayDirY)
bit 7, a
jr z, rayDirYPos1
; stepY = -1;
ld ixh, -8
; sideDistY = (posY - mapY*32) * deltaDistY / 32;
ld a, (posY)
and $1F
jp rayDirYEnd1
rayDirYPos1:
; } else {
; stepY = 1;
ld ixh, 8
; sideDistY = ((mapY + 1)*32 - posY) * deltaDistY / 32;
ld a, (posY)
and $1F ; keep fractional part
xor $1F ; subtract from 32
rayDirYEnd1:
ld h, a
ld a, (deltaDistY)
ld e, a
call mult8
; /= 32
xor a
add hl, hl
rla
add hl, hl
rla
add hl, hl
rla
ld l, h
ld h, a
ld (sideDistY), hl
; BC is pointer into map.
; IXL = stepX.
; IXH = stepY.
ld a, (mapX)
ld hl, mapY
or (hl)
ld b, high(MAZE)
ld c, a
; perform DDA
loop3:
; jump to next map square, either in x-direction, or in y-direction
; if (sideDistX < sideDistY) {
ld hl, (sideDistX)
ld de, (sideDistY)
or a ; clear carry
sbc hl, de
add hl, de
jr nc, moveY ; jump if de <= hl (y < x)
; sideDistX += deltaDistX;
ld a, (deltaDistX)
ld e, a
ld d, 0
add hl, de
ld (sideDistX), hl
; mapX += stepX;
ld a, c
add a, ixl
ld c, a
; side = 0;
xor a
ld (side), a
jp moveEnd
moveY:
; } else {
; sideDistY += deltaDistY;
ld a, (deltaDistY)
ld l, a
ld h, 0
add hl, de
ld (sideDistY), hl
; mapY += stepY;
ld a, c
add a, ixh
ld c, a
; side = 1;
ld a, 1
ld (side), a
moveEnd:
; Check if ray has hit a wall
; if (MAZE[mapY][mapX] != ' ') hit = 1;
ld a, (bc)
cp ' '
jp z, loop3
; Calculate distance projected on camera direction (Euclidean
; distance would give fisheye effect!)
; if (side == 0) {
ld a, (side)
or a
jp nz, hitYSide
; perpWallDist = sideDistX - deltaDistX;
ld hl, (sideDistX)
ld a, (deltaDistX)
ld e, a
ld d, 0
or a
sbc hl, de
ld (dist), hl
ld b, $80 ; indicate hit X side.
jp hitSideEnd
hitYSide:
; } else {
; perpWallDist = sideDistY - deltaDistY;
ld hl, (sideDistY)
ld a, (deltaDistY)
ld e, a
ld d, 0
or a
sbc hl, de
ld (dist), hl