HPAVC

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

/ HPAVC / HPAVC CD-ROM.iso / pc / VGA_VUL1.ZIP / BOARDZ.ASM next >

Wrap

Assembly Source File | 1995-06-17 | 15.8 KB | 378 lines

;==============================================================================; ; ; ; Assembler program by Vulture. ; ; This program scrolls a text and displays a 3d-starfield. ; ; It's a BBS advertisement. ; ; ; ; Current Date: 13-2-95 Vulture ; ; ; ;==============================================================================; DOSSEG ; Sort the segment using DOS standard CODE DATA STACK .MODEL SMALL ; Code is smaller than 64kB (code & data) .STACK 200h ; Specify stack .286 ; Allow 80286 instructions .CODE ; Codesegment starts here JUMPS ; Let Tasm handle out of range jumps ASSUME CS:@CODE ; cs points to codesegment ; === DATA === INCLUDE Font.dat ; File with font data INCLUDE Numbers.dat ; Include 500 random numbers between -200 and 200 Message DB 13,10,"Code by Vulture.",13,10,"$" ; Important message :) Star_Struc STRUC ; Format of star (like a record in Pascal) X DW 0 ; X-position of star Y DW 0 ; Y-position of star Z DW 0 ; Z-position of star Old DW 0 ; Where to erase old star Col DB 0 ; Color of star Star_Struc ENDS StarStrucSize = 9 ; Number of bytes per entry ( 4 wordz and a byte ) ScreenWidth EQU 320 ; Obvious ScreenHeight EQU 200 ; Obvious MaxStars EQU 250 ; Maximum number of stars MaxNumbers EQU 500 ; Number of random numbers defined MaxZ EQU 4096 ; StartZvalue for all stars MinZ EQU 0 ; If Z = 0 then star is dead XIndex DW 250 ; Index to X-numbers YIndex DW 125 ; Index to Y-numbers WarpSpeed DW 20 ; Speed of stars NumActive DW 0 ; Number of stars active Stars Star_Struc MaxStars DUP (?) ; Array of star-records Palette DB 0,0,0 ; Palette info for first 5 colors (font) DB 0,0,0 DB 52,0,0 DB 42,0,0 DB 32,0,0 DB 0,0,0 ; Base color black => R,G,B i=15 ; 16 grey shades REPT 16 DB 3*i,3*i,3*i i=i-1 ENDM PaletteArray DB 768 DUP (?) ; Array to hold the palette Text DB 'if u wanna experience some cewl boardz in the netherlands ' DB 'call firehouse 058-661590 detonator 05111-4307 or ' DB 'mark of cain 058-672111 cu around. . . . . .' DB ' ',0 ; Text to scroll Order DB 'abcdefghijklmnopqrstuvwxyz0123456789-. ' ; Order of characters ; === PROCEDURES === SetVGA PROC NEAR ; Get into VGA mode mov ax,0013h ; Set the videomode 320*200*256 int 10h ; Call VID interrupt ret SetVGA ENDP SetText PROC NEAR ; Get into character mode mov ax,0003h ; Set 80x25x16 char mode int 10h ; Call VID interrupt ret SetText ENDP WaitVrt PROC NEAR ; Waits for vertical retrace to reduce "snow" mov dx,3dah Vrt: in al,dx test al,8 jnz VRT ; Wait until Verticle Retrace starts NoVrt: in al,dx test al,8 jz NoVRT ; Wait until Verticle Retrace ends ret ; Return to main program WaitVrt ENDP SavePalette PROC NEAR ; Saves entire palette in array cli ; Disable interrupts mov bp,offset PaletteArray ; Point to start of array mov cx,768 ; Save all R,G,B registers mov dx,03c7h ; Read register mov al,0 ; Start at 0 out dx,al ; Write to port mov dx,03c9h ; Read data register Grab: in al,dx ; Read value from port and al,3fh ; Mask of upper 2 bits mov byte ptr [bp],al ; Store the value in aray inc bp ; Point to the next one loop Grab ; Loop until cx = 0 sti ; Enable interrupts ret ; Return to main program SavePalette ENDP FadeOut PROC NEAR ; Fades screen to black cli ; Disable interrupts mov bp,offset PaletteArray ; Point to start of array mov cx,64 ; Repeat 64 times (0..63) OneCycle: mov bx,0 ; Set counter Decrease: cmp byte ptr [bp],0 ; Is it 0 already ? je Fading ; Yep => Do the next dec byte ptr [bp] ; Nope => Decrease by one Fading: inc bp ; Point to next value inc bx ; Increase counter cmp bx,768 ; Have we reached the end ? jl Decrease ; No => Do another one push cx ; Save 1st loop counter call WaitVrt ; Wait for retrace sub bp,768 ; Point to start mov bx,0 ; Reset counter mov cx,768 ; Do all colors mov dx,03c8h ; Write register mov al,0 ; Start at 0 out dx,al ; Write to port inc dx ; Writing => 03c8h + 1 = 03c9h WriteAll: mov al,byte ptr [bp] ; Store value in al out dx,al ; Give it to the VGA inc bp ; Point to next one inc bx ; Increase counter loop WriteAll ; Loop while cx > 0 pop cx ; Restore 1st loop counter sub bp,768 ; Point to start loop OneCycle ; Loop while cx > 0 sti ; Enable interrupts ret ; Return to main program FadeOut ENDP CalcStar PROC NEAR pusha ; Put all registers on stack mov si,0 ; si points to first star StartCalc: ; Start searching for empty slots cmp [NumActive],MaxStars ; Check for room jae NoEmptySpace ; No room => exit SearchSlot: cmp word ptr [Stars.Z+si],MinZ ; If Z = 0 then slot is empty je FillSlot add si,StarStrucSize ; si points to next star cmp si,StarStrucSize*MaxStars ; Have we done entire array ? jb SearchSlot ; No => search again jmp NoEmptySpace ; Yes => exit FillSlot: mov di,[XIndex] ; Grab Xindex and put it in di add di,di ; Make WORD index mov ax,[Numbers+di] ; Get the number shl ax,3 ; Multiply by 8 mov [Stars.X+si],ax ; Save the number mov di,[YIndex] ; Do the same for Y add di,di mov ax,[Numbers+di] shl ax,3 mov [Stars.Y+si],ax mov [Stars.Z+si],MaxZ ; Give star the Z offset mov al,0 ; Also give it basecolor 0 (black) mov [Stars.Col+si],al ; Store the color inc [NumActive] ; Increase star counter inc [XIndex] ; Increase the X index cmp [XIndex],MaxNumbers ; Have we reached the end of the list? jb XindNotMax ; No => continue mov [XIndex],0 ; Yes => go to start of list XindNotMax: inc [YIndex] ; Increase the Y index cmp [YIndex],MaxNumbers ; Have we reached the end of the list? jb StartCalc ; No => continue mov [YIndex],0 ; Yes => go to start of list NoEmptySpace: popa ; Restore all registers ret ; Return to main program CalcStar ENDP ShowStars PROC NEAR pusha ; Save all registers mov si,0 ; si points to first record ShowLoop: mov cx,[Stars.Z+si] ; Grab Z value of star cmp cx,0 ; If Z = 0 then exit je ContinueStar ; Do the next star mov di,[Stars.Old+si] ; Get old position of star mov byte ptr es:[di],0 ; Erase the old star mov ax,[Stars.X+si] ; Grab X value of star mov dx,256 ; Multiply X with 256 imul dx idiv cx ; Divide by Z add ax,ScreenWidth/2 ; Add 160 to center it on the screen mov di,ax ; di = X cmp di,ScreenWidth ; Is the star in range ? jae TermStar ; No => Do next star mov ax,[Stars.Y+si] ; Grab an Y value mov dx,256 ; Multiply Y with 256 imul dx idiv cx ; Divide by Z (a bit slow but who carez) add ax,ScreenHeight/2 ; Add 100 to center it on the screen cmp ax,ScreenHeight ; Is the star in range ? jae TermStar ; No => Do next star cmp ax,90 ; Do not affect scroller jl InRange cmp ax,100 ; Text scrolls between 90 & 100 ja InRange jmp TermStar ; Star affects scroller so terminate it InRange: imul ax,ScreenWidth ; ax = Y * ScreenWidth add di,ax ; di = X + (Y * 320) mov [Stars.Old+si],di ; Save the position add ch,cs:[Stars.Col+si] ; Divide Z by 256 & add basecolor 0 mov al,ch ; Move color into al add al,5d ; Add 5 to avoid fontcolors mov byte ptr es:[di],al ; Place the dot on the screen mov ax,[WarpSpeed] sub cx,ax ; Decrease Z with WarpSpeed mov [Stars.Z+si],cx ; Save the new Z jmp ContinueStar ; Do the next star TermStar: mov [Stars.Z+si],MinZ ; Set Z to 0 => Star is terminated dec [NumActive] ; Decrease number of active stars ContinueStar: add si,StarStrucSize ; si points to next record cmp si,StarStrucSize*MaxStars ; Reached end of array ? jb ShowLoop ; Continue with next star popa ; Restore all registers ret ; Return to main program ShowStars ENDP ; === MAIN PROGRAM === START: cli ; Clear interrupt flag call SetVGA ; Get in GFX-mode ; === Set the palette === mov ax,cs ; Move CS into AX mov es,ax ; es points to codesegment mov ax,1012h ; Select write palette function mov bx,0 ; Start at color 0 mov cx,23 ; Write 23 colors mov dx,offset Palette ; es:dx points to palette data int 10h ; Call VID interrupt & set palette call SavePalette ; And save palette into array ; === Initialize pointers === mov ax,0a000h mov es,ax ; es points to VGA mov ax,cs mov ds,ax ; ds points to codesegment (data) ; === Start scroll === Reset: lea si,Text ; si points to start of Text Mainthing: ; Main loop lodsb ; Load a character in al (si increased) cmp al,0 ; Have we reached the end of da text ? je Reset ; Yep => Start over push si ; Save character-offset on stack mov bx,ax ; Save the character into bx mov cx,0 ; Set character-counter for position in font lea si,Order ; si points to offset Order Again: lodsb ; Load the order-character (abcdef etc...) cmp ax,bx ; Is it da same letter/character ? je Found ; Yeah => Found it. . . inc cx ; Nope => Increase character-counter jmp Again ; Compare with next character Found: mov ax,8 ; 7 pixels + black pixel = 8 pixels mul cx ; ax=ax*cx (e.g: E := 4 * 10;) mov bx,4 ; Draw 4 * 2 vertical lines Hloop: lea si,Font ; si points to start of Font add si,ax ; si now points to character mov di,320*91 ; di points to startposition on VGA mov cx,9 ; Write 9 horizontal Vloop: push cx ; Save first loop-counter mov cx,2 ; Draw 2 new horizontal pixels repz movsb ; And go ! add di,318 ; Point to next location on VGA add si,318 ; Point to next source-location pop cx ; Restore loop-counter loop Vloop ; Loop 9 times ; === Scroll the text and improve stars === push ds ax ; Save pointer to character + ds mov ax,0a000h ; VGA-segment mov ds,ax ; ds points to VGA mov si,320*90+2 ; Destination offset mov di,320*90 ; Source offset mov cx,10*320 ; Repeat factor => Number of bytes to copy rep movsb ; And go ! (Hint: why not use words instead) mov di,320*101 ; On some slow VGA-cards we have to plot mov cx,5 ; 5 black pixels just below the scroller mov al,0 ; on the left on the screen. Erase this rep stosb ; code to see what I mean. call WaitVrt ; Wait for vertical retrace call CalcStar ; Calculate new stars call ShowStars ; Show all stars on VGA ; === Want to quit ? === in al,60h ; Was ESCAPE pressed ? cmp al,1 je QuitNow ; If so, quit now. . . ; === No quit ? then continue === pop ax ds ; Restore pointer to character + ds add ax,2 ; And add 2 to point to next 2 vertical lines dec bx ; Decrease line-counter jnz Hloop ; If it's 0 then jump pop si ; Restore character-offset to do next char jmp Mainthing ; And start over again QuitNow: ; Quit everything call FadeOut ; Fade da screen to black call SetText ; Get in TXT-mode mov ax,cs mov ds,ax ; ds points to codesegment (data) lea dx,Message ; Load offset message mov ah,9 ; Select function 9 (print string) int 21h ; Print the message mov ax,4c00h ; Quit program int 21h END START ; End Of C<><>L Program !!! ; Code by Vulture. ; Thanx to Draeden of VLA for example code. ; Don't be lame. Don't just rip the code. ; Give credit where it should be. I did. ; See ya in the next release.