Bart's Pacman Hits

home *** CD-ROM | disk | FTP | other *** search

/ Bart's Pacman Hits / BPACMAN.iso / BPACMAN / COIN / INVADERS / INVADERS.ASM < prev next >

Wrap

Assembly Source File | 1995-08-14 | 129.2 KB | 2,844 lines

;-------------------------------; ; 6k Space Invaders Version 1.0 ; ; ; ; Copyright (c) by Paul S. Reid ; ; All rights reserved. ; ;-------------------------------; CODE_SEG SEGMENT ASSUME CS:CODE_SEG,DS:CODE_SEG ORG 100h BEGIN: ;---------------------------------------------------------------------------------------------------------------------------------- ; 6k Space Invaders ;---------------------------------------------------------------------------------------------------------------------------------- Start PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV AH,0 MOV AL,13h INT 10h CALL InstallNewInt9 ; Install game keyboard handler ; Seed random number generator with clock MOV AX,040h MOV ES,AX MOV AX,ES:[06ch] MOV Seed,AX ; Set color palette MOV AX,CS ; Segment of palette buffer MOV ES,AX ; in ES MOV DX,OFFSET Palette ; Offset of palette buffer in DX MOV AH,10h ; Function 10h (Get/set palette registers) MOV AL,12h ; Subfunction 12h (Set block of color registers) MOV BX,00h ; First color register to set MOV CX,05bh ; Number of color registers to set (255 = all of them) INT 10h ; Set registers ; Draw top and bottom borders MOV AX,0a000h ; Get segment of video memory MOV ES,AX ; Store it in destination segment register MOV DI,0 ; Store address in destination register MOV CX,10240 ; 32 lines DrawTop: MOV BX,0008fh ; Random number between 0 and 20 in AX MOV TempStore,CX CALL Random ; Call random routine CMP RandomNumber,1 JNZ NoStar MOV AL,12 JMP DrawTop2 NoStar: MOV AL,8 DrawTop2: STOSB MOV CX,TempStore LOOP DrawTop MOV DI,54400 ; Store address in destination register MOV CX,9600 ; 32 lines DrawBottom: MOV BX,0008fh ; Random number between 0 and 20 in AX MOV TempStore,CX CALL Random ; Call random routine CMP RandomNumber,1 JNZ NoStar2 MOV AL,12 JMP DrawBottom2 NoStar2: MOV AL,8 DrawBottom2: STOSB MOV CX,TempStore LOOP DrawBottom ;Draw Invaders logo LEA AX,LogoOutline ; Get address of sprite MOV BX,74 ; Get X position to draw sprite at MOV DL,0 ; Get Y position to draw sprite at MOV DH,10 ; Get color to draw sprite CALL DrawLogoLayer ; Draw sprite LEA AX,LogoShadow ; Get address of sprite MOV BX,74 ; Get X position to draw sprite at MOV DL,0 ; Get Y position to draw sprite at MOV DH,9 ; Get color to draw sprite CALL DrawLogoLayer ; Draw sprite LEA AX,LogoLetters ; Get address of sprite MOV BX,74 ; Get X position to draw sprite at MOV DL,0 ; Get Y position to draw sprite at MOV DH,11 ; Get color to draw sprite CALL DrawLogoLayer ; Draw sprite JMP TitleScreen ; Clear video buffer StartGame: CALL ResetGame MOV AX,CS ; Get segment of video memory MOV ES,AX ; Store it in destination segment register LEA DI,VideoBuffer ; Store address in destination register MOV CX,21760 ; 136 lines (160 * 136) MOV AX,0 ClearAll2: STOSW LOOP ClearAll2 ; Display "SCORE" LEA AX,SCO ; Get address of sprite MOV BX,80 ; Get X position to draw sprite at MOV DL,0 ; Get Y position to draw sprite at MOV DH,5 ; Get color to draw sprite CALL DrawSprite ; Draw sprite LEA AX,ORE ; Get address of sprite MOV BX,96 ; Get X position to draw sprite at MOV DL,0 ; Get Y position to draw sprite at MOV DH,5 ; Get color to draw sprite CALL DrawSprite ; Draw sprite LEA AX,PlayersShip ; Get address of sprite MOV BX,220 ; Get X position to draw sprite at MOV DL,0 ; Get Y position to draw sprite at MOV DH,5 ; Get color to draw sprite CALL DrawSprite ; Draw sprite LEA AX,Equal ; Get address of sprite MOV BX,232 ; Get X position to draw sprite at MOV DL,0 ; Get Y position to draw sprite at MOV DH,5 ; Get color to draw sprite CALL DrawSprite ; Draw sprite ; Display lives MOV AL,Lives MOV BX,239 MOV DL,0 MOV DH,5 CALL DisplayDigit CALL DisplayScore ; Outter game loop RedrawBunkers: CALL DrawBunkers MOV FirstFrame,1 ; Inner game loop NoExit: LEA AX,PlayersShip ; Get address of sprite MOV BX,PlayerX ; Get X position to draw sprite at MOV DL,130 ; Get Y position to draw sprite at MOV DH,1 ; Get color to draw sprite CALL DrawSprite ; Draw sprite CALL CheckPlayerDead CALL DisplayScore ; Prepare for buffer blit LEA SI,VideoBuffer MOV DI,10560 ; Store address in destination register MOV AX,0a000h ; Get segment of video memory MOV ES,AX ; Store it in destination segment register MOV CX,21760 ; 150 lines (136 * 150) ; Check vertical retrace MOV DX,03DAh ; Get vertical retrace port address in DX ;RetraceStart: IN AL,DX ; Grab retrace information ; TEST AL,8 ; Did it start yet? ; JNZ RetraceStart ; No, wait until it does RetraceEnd: IN AL,DX ; Grab retrace information again TEST AL,8 ; Did it end yet? JZ RetraceEnd ; No, loop until it does ; Blit buffer to video memory BlitAll: MOVSW LOOP BlitAll CMP FirstFrame,1 JNZ NoFirstFrame CALL DrawInvaders LEA AX,GetReady MOV BX,82 MOV DL,20 MOV DH,7 CALL PrintText MOV CX,0 MOV DX,0 MOV AH,1 INT 01ah Wait1: MOV AH,0 INT 01ah CMP DL,18 JB Wait1 LEA AX,GetReady MOV BX,82 MOV DL,20 MOV DH,0 CALL PrintText MOV FirstFrame,0 NoFirstFrame: CMP SoundToggle,1 JNZ NoSoundToggle MOV SoundToggle,0 XOR Sound,080h NoSoundToggle: CALL EraseInvaders DEC MoveCount JNZ NoInvaderMove CALL MoveInvaders NoInvaderMove: CMP FireToggle,1 JNZ NoFire CMP MissileX,0 JNZ NoFire CALL ShootPlayerMissile NoFire: CALL DrawInvaders CMP MissileX,0 JZ NoMissile CALL MovePlayerMissile CMP Collision,0 JZ NoMissile CALL EraseInvaders CALL EraseScore CALL CheckInvaderKill CALL DrawInvaders MOV Collision,0 ; Reset collision flag NoMissile: CMP NextLevelToggle,0 JZ NoNextLevel CALL NextLevel JMP RedrawBunkers NoNextLevel: CMP PlayerDead,0 JZ NoPlayerDead JMP KillPlayer NoPlayerDead: MOV BX,0ffffh ; Random number between 0 and 20 in AX CALL Random ; Call random routine CMP RandomNumber[0],1 JNZ NoMakeUFO CMP UFOX,0 JNZ NoMakeUFO DEC UFOCounter CMP UFOCounter,0 JNZ NoMakeUFO MOV UFOCounter,6 MOV UFOX,50 NoMakeUFO: CMP UFOX,0 JZ NoUFO CALL MoveUFO NoUFO: MOV BX,BombFreq ; Random number between 0 and 20 in AX CALL Random ; Call random routine CMP RandomNumber[0],1 JNZ NoInvaderBomb CALL InvaderBomb NoInvaderBomb: DEC BombMove CMP BombMove,0 JNZ NoMoveBombs MOV AL,BombSpeed MOV BombMove,AL CALL MoveBombs NoMoveBombs: LEA AX,PlayersShip ; Get address of sprite MOV BX,PlayerX ; Get X position to draw sprite at MOV DL,130 ; Get Y position to draw sprite at CALL EraseSprite ; Draw sprite CMP LeftToggle,1 JNZ NoLeft CALL MovePlayerLeft NoLeft: CMP RightToggle,1 JNZ NoRight CALL MovePlayerRight NoRight: CMP ExitToggle,1 JZ Exit JMP NoExit ; Clean up and exit Exit: CALL RemoveNewInt9 MOV AH,0 MOV AL,3 INT 10h MOV AH,4Ch ; Exit function INT 21h ; Call DOS for exit Start ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Reset Game ;---------------------------------------------------------------------------------------------------------------------------------- ResetGame PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV Frame,0 MOV InvadersX,275 MOV InvadersY,30 MOV InvadersToggle[0],07ff0h MOV InvadersToggle[2],07ff0h MOV InvadersToggle[4],07ff0h MOV InvadersToggle[6],07ff0h MOV InvadersToggle[8],07ff0h MOV PlayerX,154 MOV LeftToggle,0 MOV RightToggle,0 MOV FireToggle,0 MOV ExitToggle,0 MOV NextLevelToggle,0 MOV MissileX,0 MOV MissileY,0 MOV UFOX,0 MOV AX,CS ; Get segment of video memory MOV ES,AX ; Store it in destination segment register LEA DI,BombX MOV CX,22 MOV AX,0 ClearLoop1: STOSW LOOP ClearLoop1 LEA DI,BombY MOV CX,22 ClearLoop2: STOSB LOOP ClearLoop2 LEA DI,BombType MOV CX,22 ClearLoop3: STOSB LOOP ClearLoop3 MOV BombFreq,010h MOV MoveCount,1 MOV InvaderSpeed,55 MOV Direction,0 MOV Reversing,0 MOV Collision,0 MOV Score[0],48 MOV Score[1],48 MOV Score[2],48 MOV Score[3],48 MOV Score[4],48 MOV Lives,51 MOV BombMove,2 MOV BombSpeed,2 MOV PlayerDead,0 MOV GameOverToggle,0 MOV CurrentInvaderSpeed,55 MOV CurrentInvaderY,30 MOV CurrentBombFreq,010h RET ResetGame ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Print Text ;---------------------------------------------------------------------------------------------------------------------------------- PrintText PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV LetterCounter,AX MOV LetterXPos,BX MOV LetterYPos,DL MOV LetterColor,DH SUB LetterXPos,6 CMP KeyPress,1 JNZ PrintNext MOV KeyPress,0 CMP ExitToggle,1 JNZ NotExit2 JMP Exit NotExit2: CMP SoundToggle,1 JNZ NotSound MOV SoundToggle,0 XOR Sound,080h JMP PrintNext NotSound: CMP GameStart,1 JNZ PrintNext MOV GameStart,0 JMP StartGame PrintNext: MOV SI,LetterCounter LODSB INC LetterCounter ADD LetterXPos,6 CMP AL,0 JZ DonePrinting CMP AL,32 JZ PrintNext MOV BX,LetterXPos MOV DL,LetterYPos MOV DH,LetterColor CALL DisplayDigit LEA SI,VideoBuffer MOV DI,10560 ; Store address in destination register MOV AX,0a000h ; Get segment of video memory MOV ES,AX ; Store it in destination segment register MOV CX,21760 ; 150 lines (136 * 150) MOV DX,03DAh ; Get vertical retrace port address in DX RetraceEnd3: IN AL,DX ; Grab retrace information again TEST AL,8 ; Did it end yet? JZ RetraceEnd3 ; No, loop until it does BlitAll3: MOVSW LOOP BlitAll3 JMP PrintNext DonePrinting: RET LetterCounter DW 0 LetterXPos DW 0 LetterYPos DB 0 LetterColor DB 0 PrintText ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Title Screen - Never Returns! ;---------------------------------------------------------------------------------------------------------------------------------- TitleScreen PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG ; Clear video buffer MOV AX,CS ; Get segment of video memory MOV ES,AX ; Store it in destination segment register LEA DI,VideoBuffer ; Store address in destination register MOV CX,21760 ; 136 lines (160 * 136) MOV AX,0 ClearAll: STOSW LOOP ClearAll MOV KeyPress,0 MOV GameStart,1 LEA AX,InvadersTitle MOV BX,40 MOV DL,0 MOV DH,7 CALL PrintText LEA AX,Copyright MOV BX,61 MOV DL,10 MOV DH,030h CALL PrintText LEA AX,Rights MOV BX,101 MOV DL,20 MOV DH,030h CALL PrintText LEA AX,UFO ; Get address of sprite MOV DL,40 ; Get Y position to draw sprite at MOV DH,3 ; Get color to draw sprite MOV BX,100 ; Get X position to draw sprite at CALL DrawLetter ; Draw sprite LEA AX,UFOScore MOV BX,137 MOV DL,40 MOV DH,7 CALL PrintText LEA AX,TopInvader1 ; Get address of sprite MOV DL,50 ; Get Y position to draw sprite at MOV DH,010h ; Get color to draw sprite MOV BX,103 ; Get X position to draw sprite at CALL DrawLetter ; Draw sprite LEA AX,Row1Score MOV BX,137 MOV DL,50 MOV DH,7 CALL PrintText LEA AX,MiddleInvader2 ; Get address of sprite MOV DL,60 ; Get Y position to draw sprite at MOV DH,020h ; Get color to draw sprite MOV BX,103 ; Get X position to draw sprite at CALL DrawLetter ; Draw sprite LEA AX,Row2Score MOV BX,137 MOV DL,60 MOV DH,7 CALL PrintText LEA AX,MiddleInvader1 ; Get address of sprite MOV DL,70 ; Get Y position to draw sprite at MOV DH,030h ; Get color to draw sprite MOV BX,103 ; Get X position to draw sprite at CALL DrawLetter ; Draw sprite LEA AX,Row3Score MOV BX,137 MOV DL,70 MOV DH,7 CALL PrintText LEA AX,BottomInvader1 ; Get address of sprite MOV DL,80 ; Get Y position to draw sprite at MOV DH,040h ; Get color to draw sprite MOV BX,103 ; Get X position to draw sprite at CALL DrawLetter ; Draw sprite LEA AX,Row4Score MOV BX,137 MOV DL,80 MOV DH,7 CALL PrintText LEA AX,BottomInvader1 ; Get address of sprite MOV DL,90 ; Get Y position to draw sprite at MOV DH,050h ; Get color to draw sprite MOV BX,103 ; Get X position to draw sprite at CALL DrawLetter ; Draw sprite LEA AX,Row5Score MOV BX,137 MOV DL,90 MOV DH,7 CALL PrintText LEA AX,StartDocs MOV BX,79 MOV DL,109 MOV DH,050h CALL PrintText LEA AX,ExitDocs MOV BX,52 MOV DL,119 MOV DH,050h CALL PrintText LEA AX,Distribution MOV BX,4 MOV DL,129 MOV DH,7 CALL PrintText MOV GameStart,0 MOV AH,1 MOV CX,0 MOV DX,0 INT 01ah GetKey: CMP KeyPress,1 JZ KeyWasPressed MOV AH,0 INT 01ah CMP DH,1 JNZ GetKey JMP TitleScreen2 KeyWasPressed: CMP ExitToggle,1 JNZ NotExit JMP Exit NotExit: CMP SoundToggle,1 JNZ NotSound2 MOV SoundToggle,0 XOR Sound,080h JMP GetKey NotSound2: JMP StartGame TitleScreen ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Title Screen 2 - Never Returns! ;---------------------------------------------------------------------------------------------------------------------------------- TitleScreen2 PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG ; Clear video buffer MOV AX,CS ; Get segment of video memory MOV ES,AX ; Store it in destination segment register LEA DI,VideoBuffer ; Store address in destination register MOV CX,21760 ; 136 lines (160 * 136) MOV AX,0 ClearAllZ: STOSW LOOP ClearAllZ MOV KeyPress,0 MOV GameStart,1 LEA AX,InvadersTitle MOV BX,40 MOV DL,0 MOV DH,7 CALL PrintText LEA AX,Copyright MOV BX,61 MOV DL,10 MOV DH,030h CALL PrintText LEA AX,Rights MOV BX,101 MOV DL,20 MOV DH,030h CALL PrintText LEA AX,Dedication MOV BX,70 MOV DL,40 MOV DH,010h CALL PrintText LEA AX,ThankYou MOV BX,64 MOV DL,60 MOV DH,010h CALL PrintText LEA AX,SoundTog MOV BX,55 MOV DL,80 MOV DH,7 CALL PrintText LEA AX,PlayKeys MOV BX,31 MOV DL,90 MOV DH,7 CALL PrintText LEA AX,StartDocs MOV BX,79 MOV DL,109 MOV DH,050h CALL PrintText LEA AX,ExitDocs MOV BX,52 MOV DL,119 MOV DH,050h CALL PrintText LEA AX,Distribution MOV BX,4 MOV DL,129 MOV DH,7 CALL PrintText MOV GameStart,0 MOV AH,1 MOV CX,0 MOV DX,0 INT 01ah GetKey2: CMP KeyPress,1 JZ KeyWasPressed2 MOV AH,0 INT 01ah CMP DH,1 JNZ GetKey2 JMP TitleScreen KeyWasPressed2: CMP ExitToggle,1 JNZ NotExitZ JMP Exit NotExitZ: CMP SoundToggle,1 JNZ NotSound3 MOV SoundToggle,0 XOR Sound,080h JMP GetKey2 NotSound3: JMP StartGame TitleScreen2 ENDP ; Draw Letter with pause DrawLetter PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG CALL DrawSprite ; Draw sprite ; Prepare for buffer blit LEA SI,VideoBuffer MOV DI,10560 ; Store address in destination register MOV AX,0a000h ; Get segment of video memory MOV ES,AX ; Store it in destination segment register MOV CX,21760 ; 150 lines (136 * 150) ; Check vertical retrace MOV DX,03DAh ; Get vertical retrace port address in DX RetraceEnd2: IN AL,DX ; Grab retrace information again TEST AL,8 ; Did it end yet? JZ RetraceEnd2 ; No, loop until it does ; Blit buffer to video memory BlitAll2: MOVSW LOOP BlitAll2 NoKey: MOV CX,0 MOV DX,0 MOV AH,1 INT 01ah Wait2: MOV AH,0 INT 01ah CMP DL,3 JB Wait2 RET DrawLetter ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Game Over - Never Returns! ;---------------------------------------------------------------------------------------------------------------------------------- GameOver PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV GameOverToggle,1 LEA AX,GameOverMsg MOV BX,82 MOV DL,20 MOV DH,7 CALL PrintText MOV GameOverToggle,0 MOV CX,0 MOV DX,0 MOV AH,1 INT 01ah Wait3: MOV AH,0 INT 01ah CMP DL,180 JB Wait3 JMP TitleScreen GameOver ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Kill Player - Never returns! ;---------------------------------------------------------------------------------------------------------------------------------- KillPlayer PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV AL,Lives MOV BX,239 MOV DL,0 MOV DH,0 CALL DisplayDigit DEC Lives MOV AL,Lives MOV BX,239 MOV DL,0 MOV DH,5 CALL DisplayDigit CMP Lives,48 JNZ LifeLeft ; No life left - Wait for key before exiting game JMP GameOver ; Life left - Pause before continuing LifeLeft: MOV CX,0 MOV DX,0 MOV AH,1 INT 01ah Wait4: MOV AH,0 INT 01ah CMP DL,18 JB Wait4 CALL EraseInvaders CALL ResetLevel MOV BX,0 Search3: CMP [BombY+BX],0 JNZ KillBomb2 JMP NoFoundSlot1 KillBomb2: MOV KillBombs,BX MOV DL,[BombY+BX] ; Get Y position to draw sprite at CMP [BombType+BX],0 JZ AnimatedBomb4 LEA AX,StraightMissile ; Get address of sprite JMP AllDone4 AnimatedBomb4: CMP Frame,1 JNZ IsFrame004 LEA AX,TwistedMissile1 ; Get address of sprite JMP AllDone4 IsFrame004: LEA AX,TwistedMissile2 ; Get address of sprite AllDone4: SHL BX,1 MOV BX,[BombX+BX] ; Get X position to draw sprite at CALL EraseSprite ; Draw sprite MOV BX,KillBombs MOV [BombY+BX],0 ; Get X position to draw sprite at NoFoundSlot1: INC BX CMP BX,22 JZ AllBombsDead JMP Search3 AllBombsDead: JMP RedrawBunkers KillBombs DW 0 KillPlayer ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Drop Invader Bomb ;---------------------------------------------------------------------------------------------------------------------------------- InvaderBomb PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV BX,0002h CALL Random ;------------------------------------------------------------------ ; CMP RandomNumber[0],0 ; JNZ NoGood ; MOV DL,83 ; MOV AH,2 ; INT 21h ; JMP Good ;NoGood: MOV DL,32 ; MOV AH,2 ; INT 21h ;Good: MOV DL,00dh ; MOV AH,2 ; INT 21h ;------------------------------------------------------------------ MOV DH,RandomNumber[0] MOV TempRand,DH MOV BX,0000bh ; Random number between 0 and 11 in AX CALL Random ; Call random routine MOV AX,08000h MOV CH,0 MOV CL,RandomNumber[0] INC CX LoopingZ: SHR AX,1 LOOP LoopingZ MOV DL,0 TEST InvadersToggle[8],AX JZ NoRow5Invader MOV DL,44 JMP FoundY NoRow5Invader: TEST InvadersToggle[6],AX JZ NoRow4Invader MOV DL,34 JMP FoundY NoRow4Invader: TEST InvadersToggle[4],AX JZ NoRow3Invader MOV DL,24 JMP FoundY NoRow3Invader: TEST InvadersToggle[2],AX JZ NoRow2Invader MOV DL,14 JMP FoundY NoRow2Invader: TEST InvadersToggle[0],AX JZ NoInvaders MOV DL,4 FoundY: MOV AL,RandomNumber[0] MOV AH,0 MOV CL,16 MUL CL ADD AX,InvadersX SUB AX,200 ADD DL,InvadersY ; AX Holds X, DL holds Y of bomb start position MOV BX,0 Search: CMP [BombY+BX],0 JZ FoundSlot INC BX CMP BX,22 JNZ Search JMP NoInvaders ; BX Holds offset (bomb number) FoundSlot: MOV [BombY+BX],DL MOV DH,TempRand MOV [BombType+BX],DH SHL BX,1 MOV [BombX+BX],AX NoInvaders: RET TempRand DB 0 InvaderBomb ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Move Invader Bombs ;---------------------------------------------------------------------------------------------------------------------------------- MoveBombs PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV BX,0 Search2: CMP [BombY+BX],0 JNZ GotSlot JMP NoFoundSlot GotSlot: MOV TempCounter,BX MOV DL,[BombY+BX] ; Get Y position to draw sprite at CMP [BombType+BX],0 JZ AnimatedBomb1 LEA AX,StraightMissile ; Get address of sprite JMP AllDone1 AnimatedBomb1: CMP Frame,1 JNZ IsFrame001 LEA AX,TwistedMissile1 ; Get address of sprite JMP AllDone1 IsFrame001: LEA AX,TwistedMissile2 ; Get address of sprite AllDone1: SHL BX,1 MOV BX,[BombX+BX] ; Get X position to draw sprite at CALL EraseSprite ; Draw sprite MOV BX,TempCounter INC [BombY+BX] INC [BombY+BX] CMP [BombY+BX],130 JNZ DrawNextFrameA MOV [BombY+BX],0 JMP NoFoundSlot DrawNextFrameA: MOV DL,[BombY+BX] ; Get Y position to draw sprite at CMP [BombType+BX],0 JZ AnimatedBomb2 LEA AX,StraightMissile ; Get address of sprite JMP AllDone2 AnimatedBomb2: CMP Frame,1 JNZ IsFrame002 LEA AX,TwistedMissile1 ; Get address of sprite JMP AllDone2 IsFrame002: LEA AX,TwistedMissile2 ; Get address of sprite AllDone2: SHL BX,1 MOV BX,[BombX+BX] ; Get X position to draw sprite at MOV DH,06h ; Get color to draw sprite MOV Collision,0 CALL DrawSprite ; Draw sprite CMP Collision,1 JNZ NoDeadPlayer JMP KillPlayer NoDeadPlayer: CMP Collision,2 JZ KillBomb CMP Collision,4 JNZ NoAction KillBomb: MOV BX,TempCounter MOV DL,[BombY+BX] ; Get Y position to draw sprite at CMP [BombType+BX],0 JZ AnimatedBomb3 LEA AX,StraightMissile ; Get address of sprite JMP AllDone3 AnimatedBomb3: CMP Frame,1 JNZ IsFrame003 LEA AX,TwistedMissile1 ; Get address of sprite JMP AllDone3 IsFrame003: LEA AX,TwistedMissile2 ; Get address of sprite AllDone3: SHL BX,1 MOV BX,[BombX+BX] ; Get X position to draw sprite at CALL EraseSprite ; Draw sprite MOV BX,TempCounter MOV [BombY+BX],0 ; Get X position to draw sprite at CMP Collision,4 JNZ NoAction CALL KillMissile NoAction: MOV Collision,0 MOV BX,TempCounter NoFoundSlot: INC BX CMP BX,22 JZ DoneMoveBombs JMP Search2 DoneMoveBombs: RET TempCounter DW 0 MoveBombs ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Move UFO ;---------------------------------------------------------------------------------------------------------------------------------- MoveUFO PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG DEC UFOMove CMP UFOMove,0 JNZ DoneUFO MOV UFOMove,2 LEA AX,UFO ; Get address of sprite MOV BX,UFOX ; Get X position to draw sprite at MOV DL,10 ; Get Y position to draw sprite at CALL EraseSprite ; Draw sprite INC UFOX CMP UFOX,254 JNZ DoNextUFOFrame MOV UFOX,0 JMP DoneUFO DoNextUFOFrame: LEA AX,UFO ; Get address of sprite MOV BX,UFOX ; Get X position to draw sprite at MOV DL,10 ; Get Y position to draw sprite at MOV DH,3 ; Get color to draw sprite CALL DrawSprite ; Draw sprite ; Make sound TEST Sound,080h JZ NoSound1 MOV AL,0b6h OUT 043h,AL MOV AL,090h OUT 042h,AL MOV AL,000h OUT 042h,AL IN AL,061h OR AL,3 OUT 061h,AL NoSound1: MOV CX,08000h TimerZ: LOOP TimerZ IN AL,061h AND AL,0fch OUT 061h,AL DoneUFO: RET UFOMove DB 2 UFOCounter DB 6 MoveUFO ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Generate Random Number ;---------------------------------------------------------------------------------------------------------------------------------- Random PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV AX,Seed MUL BX MOV CX,65531 DIV CX MOV Seed,DX MOV RandomNumber[0],AL RET Seed DW 0 RandomNumber DB 0 Random ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Next Level ;---------------------------------------------------------------------------------------------------------------------------------- NextLevel PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG DEC CurrentInvaderSpeed ADD CurrentInvaderY,2 CMP CurrentBombFreq,0 JZ NoDecrease DEC CurrentBombFreq NoDecrease: CALL ResetLevel RET NextLevel ENDP ; Reset Level ResetLevel PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV PlayerDead,0 MOV NextLevelToggle,0 MOV Frame,0 MOV InvadersX,275 MOV AL,CurrentInvaderY MOV InvadersY,AL MOV InvadersToggle[0],07ff0h MOV InvadersToggle[2],07ff0h MOV InvadersToggle[4],07ff0h MOV InvadersToggle[6],07ff0h MOV InvadersToggle[8],07ff0h MOV MoveCount,1 MOV AL,CurrentInvaderSpeed MOV InvaderSpeed,AL MOV Direction,0 MOV Reversing,0 MOV Collision,0 MOV AX,CurrentBombFreq MOV BombFreq,AX RET CurrentInvaderSpeed DB 55 CurrentInvaderY DB 30 CurrentBombFreq DW 010h ResetLevel ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Increase Score ;---------------------------------------------------------------------------------------------------------------------------------- IncreaseScore PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG RackScore: CALL ScorePlusOne LOOP RackScore RET IncreaseScore ENDP ; Bump score up by 1 ScorePlusOne PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG INC Score[4] CMP Score[4],58 JNZ Done MOV Score[4],48 INC Score[3] CMP Score[3],58 JNZ Done MOV Score[3],48 INC Score[2] CMP Score[2],58 JNZ Done MOV Score[2],48 INC Score[1] CMP Score[1],58 JNZ Done MOV Score[1],48 INC Score[0] MOV TempCX,CX MOV AL,Lives MOV BX,239 MOV DL,0 MOV DH,0 CALL DisplayDigit INC Lives MOV AL,Lives MOV BX,239 MOV DL,0 MOV DH,5 CALL DisplayDigit MOV CX,TempCX CMP Score[0],58 JNZ Done Done: RET TempCX DW 0 ScorePlusOne ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Display Score ;---------------------------------------------------------------------------------------------------------------------------------- DisplayScore PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV AL,Score[0] MOV BX,119 MOV DL,0 MOV DH,5 CALL DisplayDigit MOV AL,Score[1] MOV BX,126 MOV DL,0 MOV DH,5 CALL DisplayDigit MOV AL,Score[2] MOV BX,133 MOV DL,0 MOV DH,5 CALL DisplayDigit MOV AL,Score[3] MOV BX,140 MOV DL,0 MOV DH,5 CALL DisplayDigit MOV AL,Score[4] MOV BX,147 MOV DL,0 MOV DH,5 CALL DisplayDigit RET DisplayScore ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Erase Score ;---------------------------------------------------------------------------------------------------------------------------------- EraseScore PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV AL,Score[0] MOV BX,119 MOV DL,0 MOV DH,0 CALL DisplayDigit MOV AL,Score[1] MOV BX,126 MOV DL,0 MOV DH,0 CALL DisplayDigit MOV AL,Score[2] MOV BX,133 MOV DL,0 MOV DH,0 CALL DisplayDigit MOV AL,Score[3] MOV BX,140 MOV DL,0 MOV DH,0 CALL DisplayDigit MOV AL,Score[4] MOV BX,147 MOV DL,0 MOV DH,0 CALL DisplayDigit RET EraseScore ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Display / Erase Digit In Decimal ;---------------------------------------------------------------------------------------------------------------------------------- DisplayDigit PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG CALL FindDigit CALL DrawSprite ; Draw sprite RET DisplayDigit ENDP FindDigit PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG ; Find Digit CMP AL,48 JNZ NotZero LEA AX,Zero JMP GotDigit NotZero: CMP AL,49 JNZ NotOne LEA AX,One JMP GotDigit NotOne: CMP AL,50 JNZ NotTwo LEA AX,Two JMP GotDigit NotTwo: CMP AL,51 JNZ NotThree LEA AX,Three JMP GotDigit NotThree: CMP AL,52 JNZ NotFour LEA AX,Four JMP GotDigit NotFour: CMP AL,53 JNZ NotFive LEA AX,Five JMP GotDigit NotFive: CMP AL,54 JNZ NotSix LEA AX,Six JMP GotDigit NotSix: CMP AL,55 JNZ NotSeven LEA AX,Seven JMP GotDigit NotSeven: CMP AL,56 JNZ NotEight LEA AX,Eight JMP GotDigit NotEight: CMP AL,57 JNZ NotNine LEA AX,Nine JMP GotDigit NotNine: CMP AL,65 JNZ NotA LEA AX,LetterA JMP GotDigit NotA: CMP AL,66 JNZ NotB LEA AX,LetterB JMP GotDigit NotB: CMP AL,67 JNZ NotC LEA AX,LetterC JMP GotDigit NotC: CMP AL,68 JNZ NotD LEA AX,LetterD JMP GotDigit NotD: CMP AL,69 JNZ NotE LEA AX,LetterE JMP GotDigit NotE: CMP AL,70 JNZ NotF LEA AX,LetterF JMP GotDigit NotF: CMP AL,71 JNZ NotG LEA AX,LetterG JMP GotDigit NotG: CMP AL,72 JNZ NotH LEA AX,LetterH JMP GotDigit NotH: CMP AL,73 JNZ NotI LEA AX,LetterI JMP GotDigit NotI: CMP AL,74 JNZ NotJ LEA AX,LetterJ JMP GotDigit NotJ: CMP AL,75 JNZ NotK LEA AX,LetterK JMP GotDigit NotK: CMP AL,76 JNZ NotL LEA AX,LetterL JMP GotDigit NotL: CMP AL,77 JNZ NotM LEA AX,LetterM JMP GotDigit NotM: CMP AL,78 JNZ NotN LEA AX,LetterN JMP GotDigit NotN: CMP AL,79 JNZ NotO LEA AX,LetterO JMP GotDigit NotO: CMP AL,80 JNZ NotP LEA AX,LetterP JMP GotDigit NotP: CMP AL,81 JNZ NotQ LEA AX,LetterQ JMP GotDigit NotQ: CMP AL,82 JNZ NotR LEA AX,LetterR JMP GotDigit NotR: CMP AL,83 JNZ NotS LEA AX,LetterS JMP GotDigit NotS: CMP AL,84 JNZ NotT LEA AX,LetterT JMP GotDigit NotT: CMP AL,85 JNZ NotU LEA AX,LetterU JMP GotDigit NotU: CMP AL,86 JNZ NotV LEA AX,LetterV JMP GotDigit NotV: CMP AL,87 JNZ NotW LEA AX,LetterW JMP GotDigit NotW: CMP AL,88 JNZ NotX LEA AX,LetterX JMP GotDigit NotX: CMP AL,89 JNZ NotY LEA AX,LetterY JMP GotDigit NotY: CMP AL,90 JNZ NotZ LEA AX,LetterZ JMP GotDigit NotZ: CMP AL,61 JNZ NotEqual LEA AX,Equal JMP GotDigit NotEqual: CMP AL,40 JNZ NotCopyright LEA AX,CopyrightSymbol JMP GotDigit NotCopyright: LEA AX,Period GotDigit: RET FindDigit ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Check If Player Is Dead ;---------------------------------------------------------------------------------------------------------------------------------- CheckPlayerDead PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG CMP InvadersToggle[8],0 JZ NoRow5Left CMP InvadersY,84 JNZ NotDead MOV PlayerDead,1 JMP NotDead NoRow5Left: CMP InvadersToggle[6],0 JZ NoRow4Left CMP InvadersY,94 JNZ NotDead MOV PlayerDead,1 JMP NotDead NoRow4Left: CMP InvadersToggle[4],0 JZ NoRow3Left CMP InvadersY,104 JNZ NotDead MOV PlayerDead,1 JMP NotDead NoRow3Left: CMP InvadersToggle[2],0 JZ NoRow2Left CMP InvadersY,114 JNZ NotDead MOV PlayerDead,1 JMP NotDead NoRow2Left: CMP InvadersY,124 JNZ NotDead MOV PlayerDead,1 NotDead: RET CheckPlayerDead ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Check Invader Killed ;---------------------------------------------------------------------------------------------------------------------------------- CheckInvaderKill PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV AL,Collision AND AL,0f0h CMP AL,050h JNZ NoRow5Kill CALL SpeedUpInvaders MOV CH,0 MOV CL,Collision AND CL,00fh INC CL MOV AX,08000h Shifting1: SHR AX,1 LOOP Shifting1 XOR InvadersToggle[8],AX MOV CX,5 CALL IncreaseScore JMP NoRow1Kill NoRow5Kill: MOV AL,Collision AND AL,0f0h CMP AL,040h JNZ NoRow4Kill CALL SpeedUpInvaders MOV CH,0 MOV CL,Collision AND CL,00fh INC CL MOV AX,08000h Shifting2: SHR AX,1 LOOP Shifting2 XOR InvadersToggle[6],AX MOV CX,10 CALL IncreaseScore JMP NoRow1Kill NoRow4Kill: MOV AL,Collision AND AL,0f0h CMP AL,030h JNZ NoRow3Kill CALL SpeedUpInvaders MOV CH,0 MOV CL,Collision AND CL,00fh INC CL MOV AX,08000h Shifting3: SHR AX,1 LOOP Shifting3 XOR InvadersToggle[4],AX MOV CX,15 CALL IncreaseScore JMP NoRow1Kill NoRow3Kill: MOV AL,Collision AND AL,0f0h CMP AL,020h JNZ NoRow2Kill CALL SpeedUpInvaders MOV CH,0 MOV CL,Collision AND CL,00fh INC CL MOV AX,08000h Shifting4: SHR AX,1 LOOP Shifting4 XOR InvadersToggle[2],AX MOV CX,20 CALL IncreaseScore JMP NoRow1Kill NoRow2Kill: MOV AL,Collision AND AL,0f0h CMP AL,010h JNZ NoRow1Kill CALL SpeedUpInvaders MOV CH,0 MOV CL,Collision AND CL,00fh INC CL MOV AX,08000h Shifting5: SHR AX,1 LOOP Shifting5 XOR InvadersToggle[0],AX MOV CX,25 CALL IncreaseScore JMP NoUFOKill NoRow1Kill: CMP Collision,3 JNZ NoUFOKill LEA AX,UFO ; Get address of sprite MOV BX,UFOX ; Get X position to draw sprite at MOV DL,10 ; Get Y position to draw sprite at CALL EraseSprite ; Draw sprite MOV UFOX,0 MOV CX,100 CALL IncreaseScore NoUFOKill: CMP InvadersToggle[0],00000h JNZ NotAllDeadYet CMP InvadersToggle[2],00000h JNZ NotAllDeadYet CMP InvadersToggle[4],00000h JNZ NotAllDeadYet CMP InvadersToggle[6],00000h JNZ NotAllDeadYet CMP InvadersToggle[8],00000h JNZ NotAllDeadYet MOV NextLevelToggle,1 NotAllDeadYet: RET CheckInvaderKill ENDP ; Speed up invaders upon a kill SpeedUpInvaders PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG CMP InvaderSpeed,1 JZ NoSpeedIncrease DEC InvaderSpeed NoSpeedIncrease: RET SpeedUpInvaders ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Move Invaders ;---------------------------------------------------------------------------------------------------------------------------------- MoveInvaders PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG TEST Reversing,080h JNZ NoReverse MOV BX,250 MOV AX,InvadersToggle[0] OR AX,InvadersToggle[2] OR AX,InvadersToggle[4] OR AX,InvadersToggle[6] OR AX,InvadersToggle[8] MOV CX,10 FindLeft: SHL AX,1 TEST AX,08000h JNZ DoneLeft SUB BX,16 LOOP FindLeft DoneLeft: MOV DX,298 MOV AX,InvadersToggle[0] OR AX,InvadersToggle[2] OR AX,InvadersToggle[4] OR AX,InvadersToggle[6] OR AX,InvadersToggle[8] MOV CX,10 SHR AX,1 SHR AX,1 SHR AX,1 FindRight: SHR AX,1 TEST AX,00001h JNZ DoneRight ADD DX,16 LOOP FindRight DoneRight: CMP InvadersX,DX JZ Reverse CMP InvadersX,BX JNZ NoReverse Reverse: XOR Direction,080h ADD InvadersY,2 MOV Reversing,080h JMP Animate NoReverse: MOV Reversing,0 TEST Direction,080h JZ MoveInvadersLeft INC InvadersX JMP Animate MoveInvadersLeft: DEC InvadersX Animate: XOR Frame,080h MOV AH,InvaderSpeed MOV MoveCount,AH ; Make sound TEST Sound,080h JZ NoSound2 MOV AL,0b6h OUT 043h,AL MOV AL,090h OUT 042h,AL MOV AL,00Fh OUT 042h,AL IN AL,061h OR AL,3 OUT 061h,AL NoSound2: MOV CX,08000h Timer1: LOOP Timer1 IN AL,061h AND AL,0fch OUT 061h,AL RET MoveInvaders ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Shoot Player Missile ;---------------------------------------------------------------------------------------------------------------------------------- ShootPlayerMissile PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV AX,PlayerX MOV MissileX,AX MOV MissileY,123 ; Make sound TEST Sound,080h JZ NoSound3 MOV AL,0b6h OUT 043h,AL MOV AL,090h OUT 042h,AL MOV AL,001h OUT 042h,AL IN AL,061h OR AL,3 OUT 061h,AL NoSound3: MOV CX,08000h Timer2: LOOP Timer2 IN AL,061h AND AL,0fch OUT 061h,AL RET ShootPlayerMissile ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Move Player Missile ;---------------------------------------------------------------------------------------------------------------------------------- MovePlayerMissile PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG LEA AX,StraightMissile ; Get address of sprite MOV BX,MissileX ; Get X position to draw sprite at MOV DL,MissileY ; Get Y position to draw sprite at CALL EraseSprite ; Draw sprite DEC MissileY DEC MissileY CMP MissileY,09 JNZ DrawNextFrame MOV MissileX,0 JMP MissileDead DrawNextFrame: LEA AX,StraightMissile ; Get address of sprite MOV BX,MissileX ; Get X position to draw sprite at MOV DL,MissileY ; Get Y position to draw sprite at MOV DH,04h ; Get color to draw sprite CALL DrawSprite ; Draw sprite CMP Collision,0 JZ MissileDead CMP Collision,4 JZ MissileDead CMP Collision,6 JZ MissileDead CALL KillMissile MissileDead: RET MovePlayerMissile ENDP ; Kill Player Missile KillMissile PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG LEA AX,StraightMissile ; Get address of sprite MOV BX,MissileX ; Get X position to draw sprite at MOV DL,MissileY ; Get Y position to draw sprite at CALL EraseSprite ; Draw sprite MOV MissileX,0 RET KillMissile ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Move Player's Ship Left ;---------------------------------------------------------------------------------------------------------------------------------- MovePlayerLeft PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG CMP PlayerX,50 JZ NoMoreLeft DEC PlayerX NoMoreLeft: RET MovePlayerLeft ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Move Player's Ship Right ;---------------------------------------------------------------------------------------------------------------------------------- MovePlayerRight PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG CMP PlayerX,259 JZ NoMoreRight INC PlayerX NoMoreRight: RET MovePlayerRight ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; New Interrupt 9 Handler - Replaces normal keyboard handler during game play ; ; Interrupt 015h: Calling AH = 04fh (check for this - Int 15 also has other ; subfuctions!) ; Routine will look at AL, where the caller (Int 9) will have ; placed the scan code. ; ; Place any new scan code for int 9 to process into AL and set ; carry flag before return. ; ; Just clear carry flag to have int 9 ignore the keypress. ;---------------------------------------------------------------------------------------------------------------------------------- ; Installs new int 9 handler InstallNewInt9 PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV AH,035h ; Ask for interrupt address function MOV AL,015h ; Interrupt we're asking for INT 021h ; Ask for it MOV Word Ptr OldInt9Address,BX ; Save current segment of interrupt MOV Word Ptr OldInt9Address[2],ES ; Save current offset of interrupt MOV AH,025h ; Insert new address for interrupt function MOV AL,015h ; Interupt we want to change MOV DX,Offset NewInt9Handler ; New address to point to (this TSR) INT 021h ; Set it RET OldInt9Address DD 0 ; Buffer for original interrupt address StoreAX DW 0 InstallNewInt9 ENDP ; Removes new int 9 handler RemoveNewInt9 PROC NEAR Assume CS:CODE_SEG,DS:NOTHING MOV AX,Word Ptr OldInt9Address[2] MOV DS,AX MOV AH,025h ; Insert new address for interrupt function MOV AL,015h ; Interupt we want to change MOV DX,Word Ptr OldInt9Address ; New address to point to (this TSR) INT 021h ; Set it RET RemoveNewInt9 ENDP ; Actual routine to be called when int 9 is tripped NewInt9Handler PROC FAR Assume CS:CODE_SEG,DS:Nothing CMP AH,04fh JNZ NotIntercept TEST AL,080h JNZ NoKeyPress MOV KeyPress,1 ; Check left arrow NoKeyPress: CMP AL,04Bh ; Has left arrow been pressed? JNZ NoLeftOn MOV LeftToggle,1 NoLeftOn: CMP AL,0CBh ; Has left arrow been released? JNZ NoLeftOff MOV LeftToggle,0 ; Check right arrow NoLeftOff: CMP AL,04Dh ; Has right arrow been pressed? JNZ NoRightOn MOV RightToggle,1 NoRightOn: CMP AL,0CDh ; Has right arrow been released? JNZ NoRightOff MOV RightToggle,0 ; Check ctrl NoRightOff: CMP AL,01Dh ; Has ctrl been pressed? JNZ NoFireOn MOV FireToggle,1 NoFireOn: CMP AL,09Dh ; Has ctrl been released? JNZ NoFireOff MOV FireToggle,0 ; Check ESC NoFireOff: CMP AL,001h ; Has ESC been pressed? JNZ NoESCOn MOV ExitToggle,1 NoESCOn: CMP AL,01fh JNZ NotIntercept MOV SoundToggle,1 ; Clear keyboard buffer (BIOS routine is still called, and it annoyingly beeps when it's buffer is full) NotIntercept: MOV StoreAX,AX MOV AX,40:[01ch] MOV 40:[01ah],AX MOV AX,StoreAX ; MOV AX,040h ; MOV ES,AX ; MOV DS,AX ; MOV DI,01ah ; MOV SI,01ch ; MOVSW CLC ; Call original interrupt routine ; CALL OldInt9Address ; Call normal interrupt routine IRET ; RET 2 ; Return from TSR NewInt9Handler ENDP ;--------------------------------------------------------------------- ; JMP StartPrint ;CharacterTable DB "0123456789ABCDEF" ;StartPrint: MOV AL,RandomNumber[0] ; MOV CX,04h ;Looper1: SHR AL,1 ; LOOP Looper1 ; LEA SI,CharacterTable ; MOV AH,0 ; ADD SI,AX ; CLD ; LODSB ; MOV DL,AL ; MOV AH,2 ; INT 21h ; MOV AL,RandomNumber[0] ; AND AL,0fh ; LEA SI,CharacterTable ; MOV AH,0 ; ADD SI,AX ; CLD ; LODSB ; MOV DL,AL ; MOV AH,2 ; INT 21h ; MOV DL,00dh ; MOV AH,2 ; INT 21h ;--------------------------------------------------------------------- ;---------------------------------------------------------------------------------------------------------------------------------- ; Draw Bunkers ;---------------------------------------------------------------------------------------------------------------------------------- DrawBunkers PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV BunkerXL,70 MOV BunkerYL,100 CALL DrawBunker MOV BunkerXL,122 MOV BunkerYL,100 CALL DrawBunker MOV BunkerXL,174 MOV BunkerYL,100 CALL DrawBunker MOV BunkerXL,226 MOV BunkerYL,100 CALL DrawBunker RET DrawBunkers ENDP ; Draw Single Bunker DrawBunker PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG LEA AX,BunkerLeftTop ; Get address of sprite MOV BX,BunkerXL ; Get X position to draw sprite at MOV DL,BunkerYL ; Get Y position to draw sprite at MOV DH,2 ; Get color to draw sprite CALL DrawSprite ; Draw sprite ADD BunkerYL,7 LEA AX,BunkerLeftMiddle ; Get address of sprite MOV BX,BunkerXL ; Get X position to draw sprite at MOV DL,BunkerYL ; Get Y position to draw sprite at MOV DH,2 ; Get color to draw sprite CALL DrawSprite ; Draw sprite ADD BunkerYL,7 LEA AX,BunkerLeftBottom ; Get address of sprite MOV BX,BunkerXL ; Get X position to draw sprite at MOV DL,BunkerYL ; Get Y position to draw sprite at MOV DH,2 ; Get color to draw sprite CALL DrawSprite ; Draw sprite ADD BunkerXL,16 SUB BunkerYL,14 LEA AX,BunkerRightTop ; Get address of sprite MOV BX,BunkerXL ; Get X position to draw sprite at MOV DL,BunkerYL ; Get Y position to draw sprite at MOV DH,2 ; Get color to draw sprite CALL DrawSprite ; Draw sprite ADD BunkerYL,7 LEA AX,BunkerRightMiddle; Get address of sprite MOV BX,BunkerXL ; Get X position to draw sprite at MOV DL,BunkerYL ; Get Y position to draw sprite at MOV DH,2 ; Get color to draw sprite CALL DrawSprite ; Draw sprite ADD BunkerYL,7 LEA AX,BunkerRightBottom; Get address of sprite MOV BX,BunkerXL ; Get X position to draw sprite at MOV DL,BunkerYL ; Get Y position to draw sprite at MOV DH,2 ; Get color to draw sprite CALL DrawSprite ; Draw sprite RET ; Done drawing, return to caller BunkerXL DW 0 BunkerYL DB 0 DrawBunker ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Draw Invaders ;---------------------------------------------------------------------------------------------------------------------------------- DrawInvaders PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV AX,InvadersX MOV InvadersXL,AX MOV AL,InvadersY MOV InvadersYL,AL LEA SI,InvadersToggle ; Setup source pointer to sprite data MOV ColorL,010h TEST Frame,80h JZ FrameIsZero1 LEA AX,TopInvader2 JMP Skip1 FrameIsZero1: LEA AX,TopInvader1 Skip1: MOV SpriteAddressL,AX CLD ; Make sure we increment SI LODSW ; Get 2 bytes from invaders alive toggles MOV Temporary2L,SI CALL DrawInvaderRow MOV ColorL,020h TEST Frame,80h JZ FrameIsZero2 LEA AX,MiddleInvader2 JMP Skip2 FrameIsZero2: LEA AX,MiddleInvader1 Skip2: MOV SpriteAddressL,AX MOV SI,Temporary2L CLD ; Make sure we increment SI LODSW ; Get 2 bytes from invaders alive toggles MOV Temporary2L,SI CALL DrawInvaderRow MOV ColorL,030h TEST Frame,80h JZ FrameIsZero3 LEA AX,MiddleInvader1 JMP Skip3 FrameIsZero3: LEA AX,MiddleInvader2 Skip3: MOV SpriteAddressL,AX MOV SI,Temporary2L CLD ; Make sure we increment SI LODSW ; Get 2 bytes from invaders alive toggles MOV Temporary2L,SI CALL DrawInvaderRow MOV ColorL,040h TEST Frame,80h JZ FrameIsZero4 LEA AX,BottomInvader2 JMP Skip4 FrameIsZero4: LEA AX,BottomInvader1 Skip4: MOV SpriteAddressL,AX MOV SI,Temporary2L CLD ; Make sure we increment SI LODSW ; Get 2 bytes from invaders alive toggles MOV Temporary2L,SI CALL DrawInvaderRow MOV ColorL,050h MOV SI,Temporary2L CLD ; Make sure we increment SI LODSW ; Get 2 bytes from invaders alive toggles MOV Temporary2L,SI CALL DrawInvaderRow MOV Collision,0 ; No collision detection on invaders - Causes problems when invaders get to bunkers RET ; Done drawing, return to caller InvadersXL DW 0 InvadersYL DB 0 Temporary2L DW 0 DrawInvaders ENDP ; Draw Row of Invaders DrawInvaderRow PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG SHL AX,1 MOV CounterL,11 DrawRow: TEST AX,8000h ; Check left most bit JZ BitIsZero1 ; Jump if bit is 0 MOV Temporary1L,AX MOV AX,SpriteAddressL ; Get address of sprite MOV BX,InvadersXL ; Get X position to draw sprite at SUB BX,200 MOV DL,InvadersYL ; Get Y position to draw sprite at MOV DH,ColorL ; Get color to draw sprite CALL DrawSprite ; Draw sprite MOV AX,Temporary1L BitIsZero1: SHL AX,1 ; Shift data left for next bit ADD InvadersXL,16 DEC CounterL INC ColorL JNZ DrawRow ADD InvadersYL,10 MOV AX,InvadersX MOV InvadersXL,AX RET ; Done drawing, return to caller CounterL DB 0 SpriteAddressL DW 0 ColorL DB 0 Temporary1L DW 0 DrawInvaderRow ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Erase Invaders ;---------------------------------------------------------------------------------------------------------------------------------- EraseInvaders PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV AX,InvadersX MOV InvadersXL,AX MOV AL,InvadersY MOV InvadersYL,AL LEA SI,InvadersToggle ; Setup source pointer to sprite data TEST Frame,80h JZ FrameIsZeroA LEA AX,TopInvader2 JMP SkipA FrameIsZeroA: LEA AX,TopInvader1 SkipA: MOV SpriteAddressL,AX CLD ; Make sure we increment SI LODSW ; Get 2 bytes from invaders alive toggles MOV Temporary2L,SI CALL EraseInvaderRow TEST Frame,80h JZ FrameIsZeroB LEA AX,MiddleInvader2 JMP SkipB FrameIsZeroB: LEA AX,MiddleInvader1 SkipB: MOV SpriteAddressL,AX MOV SI,Temporary2L CLD ; Make sure we increment SI LODSW ; Get 2 bytes from invaders alive toggles MOV Temporary2L,SI CALL EraseInvaderRow TEST Frame,80h JZ FrameIsZeroC LEA AX,MiddleInvader1 JMP SkipC FrameIsZeroC: LEA AX,MiddleInvader2 SkipC: MOV SpriteAddressL,AX MOV SI,Temporary2L CLD ; Make sure we increment SI LODSW ; Get 2 bytes from invaders alive toggles MOV Temporary2L,SI CALL EraseInvaderRow TEST Frame,80h JZ FrameIsZeroD LEA AX,BottomInvader2 JMP SkipD FrameIsZeroD: LEA AX,BottomInvader1 SkipD: MOV SpriteAddressL,AX MOV SI,Temporary2L CLD ; Make sure we increment SI LODSW ; Get 2 bytes from invaders alive toggles MOV Temporary2L,SI CALL EraseInvaderRow MOV SI,Temporary2L CLD ; Make sure we increment SI LODSW ; Get 2 bytes from invaders alive toggles MOV Temporary2L,SI CALL EraseInvaderRow RET ; Done drawing, return to caller EraseInvaders ENDP ; Erase Row of Invaders EraseInvaderRow PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG SHL AX,1 MOV CounterL,11 DrawRowA: TEST AX,8000h ; Check left most bit JZ BitIsZeroA ; Jump if bit is 0 MOV Temporary1L,AX MOV AX,SpriteAddressL ; Get address of sprite MOV BX,InvadersXL ; Get X position to draw sprite at SUB BX,200 MOV DL,InvadersYL ; Get Y position to draw sprite at CALL EraseSprite ; Draw sprite MOV AX,Temporary1L BitIsZeroA: SHL AX,1 ; Shift data left for next bit ADD InvadersXL,16 DEC CounterL JNZ DrawRowA ADD InvadersYL,10 MOV AX,InvadersX MOV InvadersXL,AX RET ; Done drawing, return to caller EraseInvaderRow ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Draw Logo Layer ;---------------------------------------------------------------------------------------------------------------------------------- DrawLogoLayer PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV SI,AX ; Setup source pointer to sprite data MOV AL,DL ; Get Y position of sprite in AL MOV AH,0 ; Zero high byte of AX for following shifts SHL AX,1 ; Calculate Y position * 320 (find address of row) SHL AX,1 ; Y Position shifted left 6 times + Y Position shifted left 8 times SHL AX,1 SHL AX,1 SHL AX,1 SHL AX,1 MOV CX,AX SHL CX,1 SHL CX,1 ADD AX,CX ADD AX,BX ; Add X position to address MOV DI,AX ; Store address in destination register MOV AX,0a000h ; Get segment of video memory MOV ES,AX ; Store it in destination segment register MOV Row,5 DoNextRow: MOV Column,11 DoNextSprite: MOV DL,7 ; Do 7 lines of sprite CLD ; Make sure we increment SI and DI DrawLinesZ: LODSW ; Get 2 bytes from sprite data (16 bits = 1 line of sprite image) MOV BX,AX ; Transfer data to an unused register MOV CX,16 ; Scan all 16 bits DoLineZ: TEST BX,8000h ; Check left most bit JZ BitIsZeroZ ; Jump if bit is 0 MOV AL,DH ; Bit is 1, get color of sprite STOSB ; And draw the pixel on the screen JMP SkipZ ; Skip the bit is 0 stuff BitIsZeroZ: INC DI ; Bit was 0, increment destination register SkipZ: SHL BX,1 ; Shift data left for next bit LOOP DoLineZ ; Keep going until no more bits to check ADD DI,304 ; Increment address to next screen line (320 - 16 bits) DEC DL ; Decrease line count JNZ DrawLinesZ ; Draw lines until no more lines left to draw SUB DI,2224 ; Do next sprite in row DEC Column CMP Column,0 JNZ DoNextSprite ADD DI,2064 ; Do next sprite in row DEC Row CMP Row,0 JNZ DoNextRow RET ; Done drawing, return to caller Column DB 0 Row DB 0 DrawLogoLayer ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Draw Sprite ;---------------------------------------------------------------------------------------------------------------------------------- DrawSprite PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV SI,AX ; Setup source pointer to sprite data MOV AL,DL ; Get Y position of sprite in AL MOV AH,0 ; Zero high byte of AX for following shifts SHL AX,1 ; Calculate Y position * 320 (find address of row) SHL AX,1 ; Y Position shifted left 6 times + Y Position shifted left 8 times SHL AX,1 SHL AX,1 SHL AX,1 SHL AX,1 MOV CX,AX SHL CX,1 SHL CX,1 ADD AX,CX LEA CX,VideoBuffer ; Get address of video buffer ADD AX,CX ; Add offset to video buffer ADD AX,BX ; Add X position to address MOV DI,AX ; Store address in destination register MOV AX,CS ; Get segment of video memory MOV ES,AX ; Store it in destination segment register MOV DL,7 ; Do 7 lines CLD ; Make sure we increment SI and DI DrawLines: LODSW ; Get 2 bytes from sprite data (16 bits = 1 line of sprite image) MOV BX,AX ; Transfer data to an unused register MOV CX,16 ; Scan all 16 bits DoLine: TEST BX,8000h ; Check left most bit JZ BitIsZero ; Jump if bit is 0 CMP Collision,0 JNZ NoCollision MOV AL,ES:[DI] CMP AL,0 JZ NoCollision MOV Collision,AL NoCollision: MOV AL,DH ; Bit is 1, get color of sprite STOSB ; And draw the pixel on the screen JMP Skip ; Skip the bit is 0 stuff BitIsZero: INC DI ; Bit was 0, increment destination register Skip: SHL BX,1 ; Shift data left for next bit LOOP DoLine ; Keep going until no more bits to check ADD DI,304 ; Increment address to next screen line (320 - 16 bits) DEC DL ; Decrease line count JNZ DrawLines ; Draw lines until no more lines left to draw RET ; Done drawing, return to caller DrawSprite ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Erase Sprite ;---------------------------------------------------------------------------------------------------------------------------------- EraseSprite PROC NEAR Assume CS:CODE_SEG,DS:CODE_SEG MOV SI,AX ; Setup source pointer to sprite data MOV AL,DL ; Get Y position of sprite in AL MOV AH,0 ; Zero high byte of AX for following shifts SHL AX,1 ; Calculate Y position * 320 (find address of row) SHL AX,1 ; Y Position shifted left 6 times + Y Position shifted left 8 times SHL AX,1 SHL AX,1 SHL AX,1 SHL AX,1 MOV CX,AX SHL CX,1 SHL CX,1 ADD AX,CX LEA CX,VideoBuffer ; Get address of video buffer ADD AX,CX ; Add offset to video buffer ADD AX,BX ; Add X position to address MOV DI,AX ; Store address in destination register MOV AX,CS ; Get segment of video memory MOV ES,AX ; Store it in destination segment register MOV DL,7 ; Do 7 lines CLD ; Make sure we increment SI and DI DrawLines2: LODSW ; Get 2 bytes from sprite data (16 bits = 1 line of sprite image) MOV BX,AX ; Transfer data to an unused register MOV CX,16 ; Scan all 16 bits DoLine2: TEST BX,8000h ; Check left most bit JZ BitIsZero2 ; Jump if bit is 0 MOV AL,0 ; Bit is 1, get color of sprite STOSB ; And draw the pixel on the screen JMP SkipAA ; Skip the bit is 0 stuff BitIsZero2: INC DI ; Bit was 0, increment destination register SkipAA: SHL BX,1 ; Shift data left for next bit LOOP DoLine2 ; Keep going until no more bits to check ADD DI,304 ; Increment address to next screen line (320 - 16 bits) DEC DL ; Decrease line count JNZ DrawLines2 ; Draw lines until no more lines left to draw RET ; Done drawing, return to caller EraseSprite ENDP ;---------------------------------------------------------------------------------------------------------------------------------- ; Sprite data ;---------------------------------------------------------------------------------------------------------------------------------- TopInvader1 DW 0c00h,1e00h,2d00h,3f00h,1200h,2100h,1200h TopInvader2 DW 0c00h,1e00h,2d00h,3f00h,1200h,2100h,4080h MiddleInvader1 DW 2100h,9e40h,0ad40h,7f80h,3f00h,2100h,4080h MiddleInvader2 DW 2100h,1e00h,2d00h,7f80h,0bf40h,0a140h,1200h BottomInvader1 DW 01e00h,7f80h,0ccc0h,0ffc0h,2100h,4c80h,2100h BottomInvader2 DW 01e00h,7f80h,0ccc0h,0ffc0h,2100h,4c80h,8040h TwistedMissile1 DW 0000h,0000h,0000h,0800h,0400h,0800h,0400h TwistedMissile2 DW 0000h,0000h,0000h,0400h,0800h,0400h,0800h UFO DW 0ff0h,0ff0h,0ffffh,0ffffh,0ffffh,7ffeh,3ffch PlayersShip DW 0400h,0e00h,7fc0h,0ffe0h,0ffe0h,0ffe0h,0000h StraightMissile DW 0000h,0000h,0000h,0400h,0400h,0400h,0400h BunkerLeftTop DW 0fffh,1fffh,3fffh,7fffh,0ffffh,0ffffh,0ffffh BunkerLeftMiddle DW 0ffffh,0ffffh,0ffffh,0ffffh,0ffffh,0ffffh,0ffffh BunkerLeftBottom DW 0ff81h,0fe00h,0fc00h,0f800h,0f800h,0f000h,0000h BunkerRightTop DW 0f000h,0f800h,0fc00h,0fe00h,0ff00h,0ff00h,0ff00h BunkerRightMiddle DW 0ff00h,0ff00h,0ff00h,0ff00h,0ff00h,0ff00h,0ff00h BunkerRightBottom DW 0ff00h,7f00h,3f00h,1f00h,1f00h,0f00h,0000h SCO DW 71c7h,8a28h,8208h,7208h,0a08h,8a28h,71c7h ORE DW 3cf8h,0a280h,0a280h,0bcf0h,0a280h,0a280h,22f8h Zero DW 3800h,4400h,4c00h,5400h,6400h,4400h,3800h One DW 1000h,3000h,1000h,1000h,1000h,1000h,3800h Two DW 3800h,4400h,0400h,1800h,2000h,4000h,7c00h Three DW 3800h,4400h,0400h,1800h,0400h,4400h,3800h Four DW 4400h,4400h,4400h,7c00h,0400h,0400h,0400h Five DW 7c00h,4000h,4000h,7800h,0400h,4400h,3800h Six DW 3800h,4400h,4000h,7800h,4400h,4400h,3800h Seven DW 7c00h,0400h,0800h,1000h,1000h,1000h,1000h Eight DW 3800h,4400h,4400h,3800h,4400h,4400h,3800h Nine DW 3800h,4400h,4400h,3c00h,0400h,4400h,3800h Equal DW 0000h,0000h,7c00h,0000h,7c00h,0000h,0000h Period DW 0000h,0000h,0000h,0000h,0000h,0000h,1000h CopyrightSymbol DW 1e00h,2100h,4c80h,4880h,4c80h,2100h,1e00h LetterA DW 3800h,4400h,4400h,7c00h,4400h,4400h,4400h LetterB DW 7800h,4400h,4400h,7800h,4400h,4400h,7800h LetterC DW 3800h,4400h,4000h,4000h,4000h,4400h,3800h LetterD DW 7800h,4400h,4400h,4400h,4400h,4400h,7800h LetterE DW 7c00h,4000h,4000h,7800h,4000h,4000h,7c00h LetterF DW 7c00h,4000h,4000h,7800h,4000h,4000h,4000h LetterG DW 3800h,4400h,4000h,5c00h,4400h,4400h,3800h LetterH DW 4400h,4400h,4400h,7c00h,4400h,4400h,4400h LetterI DW 7c00h,1000h,1000h,1000h,1000h,1000h,7c00h LetterJ DW 0400h,0400h,0400h,0400h,0400h,4400h,3800h LetterK DW 4400h,4800h,5000h,6000h,5000h,4800h,4400h LetterL DW 4000h,4000h,4000h,4000h,4000h,4000h,7c00h LetterM DW 4400h,6c00h,5400h,4400h,4400h,4400h,4400h LetterN DW 4400h,6400h,5400h,4c00h,4400h,4400h,4400h LetterO DW 3800h,4400h,4400h,4400h,4400h,4400h,3800h LetterP DW 7800h,4400h,4400h,7800h,4000h,4000h,4000h LetterQ DW 3800h,4400h,4400h,4400h,4400h,4c00h,3c00h LetterR DW 7800h,4400h,4400h,7800h,4400h,4400h,4400h LetterS DW 3800h,4400h,4000h,3800h,0400h,4400h,3800h LetterT DW 7c00h,1000h,1000h,1000h,1000h,1000h,1000h LetterU DW 4400h,4400h,4400h,4400h,4400h,4400h,3800h LetterV DW 4400h,4400h,4400h,4400h,4400h,2800h,1000h LetterW DW 4400h,4400h,4400h,4400h,5400h,6c00h,4400h LetterX DW 4400h,4400h,2800h,1000h,2800h,4400h,4400h LetterY DW 4400h,4400h,2800h,1000h,1000h,1000h,1000h LetterZ DW 7c00h,0400h,0800h,1000h,2000h,4000h,7c00h LogoOutline DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,007ffh,01800h,02000h,04000h,040ffh,0403fh DW 00000h,0e3ffh,01400h,00c00h,00400h,00607h,0fa03h DW 00000h,0f80fh,00610h,00120h,000a0h,0c0e0h,0c0c1h DW 00000h,0fc00h,00200h,00101h,00102h,00082h,08084h DW 00000h,01fffh,06000h,08000h,00060h,000a0h,0011fh DW 00000h,003ffh,08400h,04800h,04800h,0500fh,0900fh DW 00000h,0ff80h,00040h,00040h,00080h,0ff00h,0c000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 02000h,01c00h,003fch,00fc3h,0103eh,01000h,00800h DW 0e200h,01900h,00503h,00301h,00281h,00280h,00440h DW 00181h,00682h,0f903h,00100h,00200h,08207h,04408h DW 08044h,04048h,0c028h,00028h,00018h,0e018h,0100ch DW 00100h,00200h,00200h,0047eh,00381h,00001h,00003h DW 02000h,02000h,0403fh,04020h,0803fh,08000h,00000h DW 02000h,02000h,0c000h,00000h,0f000h,00800h,00800h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,01fe0h,02011h,02009h,01009h DW 00000h,00000h,00000h,0fc0fh,00310h,000d0h,00038h DW 00700h,000ffh,00000h,0f1feh,00a01h,00600h,00300h DW 03840h,0c03fh,00000h,00fe0h,01010h,09010h,05010h DW 04408h,083f0h,00000h,07fe0h,08010h,08008h,08004h DW 0100bh,00ff0h,00000h,00fffh,01000h,01000h,01000h DW 0000dh,0fff0h,00000h,0f80fh,00610h,00110h,00090h DW 00000h,0ffffh,00000h,0fff8h,00005h,00005h,0000ah DW 01000h,0e000h,00000h,0ffffh,00000h,00000h,00000h DW 00000h,00000h,00000h,0803fh,060c0h,01100h,00a00h DW 00000h,00000h,00000h,0ff00h,00080h,00040h,00040h DW 01005h,00804h,00802h,00402h,00401h,00201h,00200h DW 00008h,0800ch,08003h,08000h,080c0h,04070h,0c04ch DW 00280h,00140h,00140h,000a0h,00090h,00048h,00044h DW 02809h,02809h,01809h,00c0ah,0040ah,00406h,00206h DW 00002h,00002h,00001h,00600h,00500h,00780h,00000h DW 0100fh,01009h,0100ah,0900ah,0900ah,0500ch,0300ch DW 000a0h,000a0h,000a0h,000a0h,000c0h,000c0h,000c0h DW 03ff2h,03f04h,00084h,00084h,0ff08h,08008h,0ffc8h DW 001c0h,001c0h,00000h,00000h,003c0h,00240h,00440h DW 00a07h,00a07h,03100h,040e0h,0201ch,017e6h,00818h DW 0e040h,09f80h,07000h,00800h,00400h,00400h,00400h DW 00100h,00100h,00080h,0007fh,00000h,00000h,00000h DW 0a023h,06020h,06010h,09fe0h,00000h,00000h,00000h DW 00022h,0c021h,03010h,00fe0h,00000h,00000h,00000h DW 00004h,00004h,0c004h,03ffbh,00000h,00000h,00000h DW 00000h,003e0h,00420h,0f81fh,00000h,00000h,00000h DW 03000h,01000h,01000h,0efffh,00000h,00000h,00000h DW 00140h,00680h,01880h,0e07fh,00000h,00000h,00000h DW 00030h,00030h,00050h,0ff8fh,00000h,00000h,00000h DW 00420h,00410h,00810h,0f00fh,00000h,00000h,00000h DW 00800h,00800h,00c00h,0f3ffh,00000h,00000h,00000h DW 00400h,00800h,07000h,08000h,00000h,00000h,00000h LogoLetters DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,007ffh,01fffh,03fffh,03f00h,03fc0h DW 00000h,00000h,0e3ffh,0f3ffh,0fbffh,0f9f8h,001fch DW 00000h,00000h,0f80fh,0fe1fh,0ff1fh,03f3fh,03f3eh DW 00000h,00000h,0fc00h,0fe00h,0fe01h,0ff01h,07f03h DW 00000h,00000h,01fffh,07fffh,0ff9fh,0ff1fh,0fe00h DW 00000h,00000h,003ffh,087ffh,087ffh,08ff0h,00ff0h DW 00000h,00000h,0ff80h,0ff80h,0ff00h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 01fffh,003ffh,00003h,00000h,00fc1h,00fffh,007ffh DW 001ffh,0e0ffh,0f8fch,0fcfeh,0fc7eh,0fc7fh,0f83fh DW 0fe7eh,0f87ch,000fch,000ffh,001ffh,001f8h,083f0h DW 07f83h,03f87h,03fc7h,0ffc7h,0ffe7h,01fe7h,00ff3h DW 0fe00h,0fc00h,0fc00h,0f800h,0fc7eh,0fffeh,0fffch DW 01fffh,01fffh,03fc0h,03fc0h,07fc0h,07fffh,0ffffh DW 0c000h,0c000h,00000h,00000h,00000h,0f000h,0f000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,01fe0h,01ff0h,00ff0h DW 00000h,00000h,00000h,00000h,0fc0fh,0ff0fh,0ffc7h DW 000ffh,00000h,00000h,00000h,0f1feh,0f9ffh,0fcffh DW 0c03fh,00000h,00000h,00000h,00fe0h,00fe0h,08fe0h DW 083f0h,00000h,00000h,00000h,07fe0h,07ff0h,07ff8h DW 00ff0h,00000h,00000h,00000h,00fffh,00fffh,00fffh DW 0fff0h,00000h,00000h,00000h,0f80fh,0fe0fh,0ff0fh DW 0ffffh,00000h,00000h,00000h,0fff8h,0fff8h,0fff1h DW 0e000h,00000h,00000h,00000h,0ffffh,0ffffh,0ffffh DW 00000h,00000h,00000h,00000h,0803fh,0e0ffh,0f1ffh DW 00000h,00000h,00000h,00000h,0ff00h,0ff80h,0ff80h DW 00ff8h,007f8h,007fch,003fch,003feh,001feh,001ffh DW 0fff7h,07ff3h,07ffch,07fffh,07f3fh,03f8fh,03f83h DW 0fc7fh,0fe3fh,0fe3fh,0ff1fh,0ff0fh,0ff87h,0ff83h DW 0c7f0h,0c7f0h,0e7f0h,0f3f1h,0fbf1h,0fbf9h,0fdf9h DW 0fffch,0fffch,0fffeh,0f9ffh,0f8ffh,0f87fh,0ffffh DW 00ff0h,00ff0h,00ff1h,00ff1h,00ff1h,08ff3h,0cff3h DW 0ff1fh,0ff1fh,0ff1fh,0ff1fh,0ff3fh,0ff3fh,0ff3fh DW 0c001h,0c003h,0ff03h,0ff03h,00007h,00007h,00007h DW 0fe3fh,0fe3fh,0ffffh,0ffffh,0fc3fh,0fc3fh,0f83fh DW 0f1f8h,0f1f8h,0c0ffh,0801fh,0c003h,0e001h,0f7e7h DW 01f80h,00000h,08000h,0f000h,0f800h,0f800h,0f800h DW 000ffh,000ffh,0007fh,00000h,00000h,00000h,00000h DW 01fc0h,09fc0h,09fe0h,00000h,00000h,00000h,00000h DW 0ffc1h,03fc0h,00fe0h,00000h,00000h,00000h,00000h DW 0fffbh,0fffbh,03ffbh,00000h,00000h,00000h,00000h DW 0ffffh,0f81fh,0f81fh,00000h,00000h,00000h,00000h DW 0cfffh,0efffh,0efffh,00000h,00000h,00000h,00000h DW 0fe3fh,0f87fh,0e07fh,00000h,00000h,00000h,00000h DW 0ffcfh,0ffcfh,0ff8fh,00000h,00000h,00000h,00000h DW 0f81fh,0f80fh,0f00fh,00000h,00000h,00000h,00000h DW 0f7ffh,0f7ffh,0f3ffh,00000h,00000h,00000h,00000h DW 0f800h,0f000h,08000h,00000h,00000h,00000h,00000h LogoShadow DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 01fffh,07800h,0e000h,0c000h,08000h,00000h,00000h DW 087ffh,00400h,00000h,00000h,00000h,00000h,00000h DW 0f00fh,00410h,00000h,00000h,00000h,00000h,00000h DW 0fc00h,00200h,00000h,00000h,00000h,00000h,00000h DW 00fffh,02000h,08000h,00000h,00000h,00000h,00000h DW 080ffh,0c000h,04000h,00000h,00000h,00000h,00000h DW 0ffe0h,00060h,00000h,00000h,00000h,00000h,03000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,03c00h,0303ch,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00001h,00000h,00000h,00000h,00000h,00000h DW 00000h,08000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,0003fh,00381h,00000h,00000h,00000h DW 00000h,00000h,00000h,0001fh,00000h,00000h,00000h DW 00000h,00000h,00000h,0fc00h,00c00h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,0ff03h,0e003h,04002h,04002h,02000h DW 00000h,00000h,0f03fh,00030h,00000h,00000h,00000h DW 00000h,00000h,0c3fch,00200h,00000h,00000h,00000h DW 00000h,00000h,01fc0h,01000h,00000h,00000h,00000h DW 00000h,00000h,07fe0h,00010h,00008h,00004h,00000h DW 00000h,00000h,00fffh,00000h,00000h,00000h,00000h DW 00000h,00000h,0f807h,00600h,00100h,00000h,00000h DW 00000h,00000h,0fffch,00004h,00000h,00000h,00000h DW 00000h,00000h,03fffh,00000h,00000h,00000h,00000h DW 00000h,00000h,0e007h,07800h,01c00h,00c00h,00400h DW 00000h,00000h,0ffe0h,000f0h,00070h,00030h,00000h DW 02000h,01001h,01001h,00800h,00800h,00400h,00400h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00001h,00000h,00000h,00200h,00000h,00000h DW 00000h,00000h,00000h,00000h,04000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00080h,00000h,00000h,00000h,07fe0h,00020h DW 00000h,00000h,00000h,00000h,00000h,00000h,00200h DW 00000h,00000h,00000h,03800h,01ce0h,00818h,00000h DW 00000h,06000h,00f00h,00700h,00300h,00300h,00200h DW 00200h,00000h,00000h,00000h,00000h,00000h,00000h DW 04000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h DW 00000h,00000h,00000h,00000h,00000h,00000h,00000h ;---------------------------------------------------------------------------------------------------------------------------------- ; Variables ;---------------------------------------------------------------------------------------------------------------------------------- GameStart DB 0 Frame DB 0 InvadersX DW 275 InvadersY DB 30 InvadersToggle DW 07ff0h,07ff0h,07ff0h,07ff0h,07ff0h PlayerX DW 154 LeftToggle DB 0 RightToggle DB 0 FireToggle DB 0 ExitToggle DB 0 SoundToggle DB 0 KeyPress DB 0 Sound DB 080h NextLevelToggle DB 0 MissileX DW 0 MissileY DB 0 UFOX DW 0 BombX DW 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 BombY DB 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 BombType DB 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 BombFreq DW 010h MoveCount DB 1 InvaderSpeed DB 55 Direction DB 0 Reversing DB 0 Collision DB 0 Score DB 48,48,48,48,48 FirstFrame DB 0 Lives DB 51 BombMove DB 2 BombSpeed DB 2 PlayerDead DB 0 GameOverToggle DB 0 InvadersTitle DB "S P A C E I N V A D E R S",0 Copyright DB "COPYRIGHT ( 1995 BY PAUL S. REID",0 Rights DB "ALL RIGHTS RESERVED.",0 UFOScore DB "= 100 POINTS",0 Row1Score DB "= 25 POINTS",0 Row2Score DB "= 20 POINTS",0 Row3Score DB "= 15 POINTS",0 Row4Score DB "= 10 POINTS",0 Row5Score DB "= 5 POINTS",0 StartDocs DB "PRESS ANY KEY TO START GAME",0 ExitDocs DB "PRESS ESC AT ANY TIME TO EXIT TO DOS",0 Dedication DB "...DEDICATED TO MY WIFE DEB...",0 ThankYou DB "THANKS TO BRENT KYLE AND TOM SWAN",0 SoundTog DB "PRESS S TO TOGGLE SOUND AT ANY TIME",0 PlayKeys DB "LEFT AND RIGHT CURSOR TO MOVE. CTRL TO FIRE",0 Distribution DB ".THIS GAME AND SOURCE CODE ARE FREELY DISTRIBUTABLE.",0 GameOverMsg DB "G A M E O V E R",0 GetReady DB "G E T R E A D Y",0 TempStore DW 0 Palette DB 00,00,00 ; Background DB 21,63,63 ; Player's Ship DB 63,21,21 ; Bunker DB 63,21,21 ; UFO DB 63,63,63 ; Missiles DB 21,63,21 ; Status Letters DB 63,63,00 ; Bombs DB 63,63,63 ; DOS text (just for diagnostic printing if required) DB 12,00,21 ; Top and bottom border backgrounds DB 33,00,42 ; Logo shadow color DB 00,00,00 ; Logo outline color DB 63,63,00 ; Logo letters color DB 41,41,41 ; Logo stars DB 00,00,00 DB 00,00,00 DB 00,00,00 DB 21,63,21 ; Row 1 invader 1 DB 21,63,21 ; Row 1 invader 2 DB 21,63,21 ; Row 1 invader 3 DB 21,63,21 ; Row 1 invader 4 DB 21,63,21 ; Row 1 invader 5 DB 21,63,21 ; Row 1 invader 6 DB 21,63,21 ; Row 1 invader 7 DB 21,63,21 ; Row 1 invader 8 DB 21,63,21 ; Row 1 invader 9 DB 21,63,21 ; Row 1 invader 10 DB 21,63,21 ; Row 1 invader 11 DB 00,00,00 DB 00,00,00 DB 00,00,00 DB 00,00,00 DB 00,00,00 DB 21,63,21 ; Row 2 invader 1 DB 21,63,21 ; Row 2 invader 2 DB 21,63,21 ; Row 2 invader 3 DB 21,63,21 ; Row 2 invader 4 DB 21,63,21 ; Row 2 invader 5 DB 21,63,21 ; Row 2 invader 6 DB 21,63,21 ; Row 2 invader 7 DB 21,63,21 ; Row 2 invader 8 DB 21,63,21 ; Row 2 invader 9 DB 21,63,21 ; Row 2 invader 10 DB 21,63,21 ; Row 2 invader 11 DB 00,00,00 DB 00,00,00 DB 00,00,00 DB 00,00,00 DB 00,00,00 DB 21,63,63 ; Row 3 invader 1 DB 21,63,63 ; Row 3 invader 2 DB 21,63,63 ; Row 3 invader 3 DB 21,63,63 ; Row 3 invader 4 DB 21,63,63 ; Row 3 invader 5 DB 21,63,63 ; Row 3 invader 6 DB 21,63,63 ; Row 3 invader 7 DB 21,63,63 ; Row 3 invader 8 DB 21,63,63 ; Row 3 invader 9 DB 21,63,63 ; Row 3 invader 10 DB 21,63,63 ; Row 3 invader 11 DB 00,00,00 DB 00,00,00 DB 00,00,00 DB 00,00,00 DB 00,00,00 DB 21,63,63 ; Row 4 invader 1 DB 21,63,63 ; Row 4 invader 2 DB 21,63,63 ; Row 4 invader 3 DB 21,63,63 ; Row 4 invader 4 DB 21,63,63 ; Row 4 invader 5 DB 21,63,63 ; Row 4 invader 6 DB 21,63,63 ; Row 4 invader 7 DB 21,63,63 ; Row 4 invader 8 DB 21,63,63 ; Row 4 invader 9 DB 21,63,63 ; Row 4 invader 10 DB 21,63,63 ; Row 4 invader 11 DB 00,00,00 DB 00,00,00 DB 00,00,00 DB 00,00,00 DB 00,00,00 DB 63,21,63 ; Row 5 invader 1 DB 63,21,63 ; Row 5 invader 2 DB 63,21,63 ; Row 5 invader 3 DB 63,21,63 ; Row 5 invader 4 DB 63,21,63 ; Row 5 invader 5 DB 63,21,63 ; Row 5 invader 6 DB 63,21,63 ; Row 5 invader 7 DB 63,21,63 ; Row 5 invader 8 DB 63,21,63 ; Row 5 invader 9 DB 63,21,63 ; Row 5 invader 10 DB 63,21,63 ; Row 5 invader 11 VideoBuffer DB 0 CODE_SEG ENDS END BEGIN