[Github] [TL;DR documentation]
Demos:
| @ | hex | disassembled asm | original asm (for comparison) | Screen capture |
|---|---|---|---|---|
| 0100 0102 0103 0105 0107 010A 010B 010F 0111 0116 0117 011A 011B 011E 0120 0122 0124 0126 0127 0128 0129 012A 012B 012C 012D 012E 012F 0130 0131 0132 0133 0134 0135 0136 0137 0138 0139 013A 013B 013C 013D 013E 013F 0140 0141 0142 0143 0144 0145 0146 0147 0148 0149 014A 014B 014C 014D 014E 014F 0150 0151 0152 0153 0154 0155 0156 0157 0158 0159 015A 015B 015C 015D 015E 015F 0160 0161 0162 0163 0164 0165 0166 0167 0168 0169 016A 016B 016C 016D 016E 016F 0170 0171 0172 0173 0174 0175 0176 0177 0178 0179 017A 017B 017C 017D 017E 017F 0180 0181 0182 0183 0184 0185 0186 0187 0188 0189 018A 018B 018C 018D 018E 018F 0190 0191 0192 0193 0194 0195 0196 0197 0198 0199 019A 019B 019C 019D 019E 019F 01A0 01A1 01A2 01A3 01A4 01A5 01A6 01A7 01A8 01A9 01AA 01AB 01AC 01AD 01AE 01AF 01B0 01B1 01B2 01B3 01B4 01B5 01B6 01B7 01B8 01B9 01BA 01BB 01BC 01BD 01BE 01BF 01C0 01C1 01C2 01C3 01C4 01C5 01C6 01C7 01C8 01C9 01CA 01CB 01CC 01CD 01CE 01CF 01D0 01D1 01D2 01D3 01D4 01D5 01D6 01D7 01D8 01D9 01DA 01DB 01DC 01DD 01DE 01DF 01E0 01E1 01E2 01E3 01E4 01E5 01E6 01E7 01E8 01E9 01EA 01EB 01EC 01ED 01EE 01EF 01F0 01F1 01F2 01F3 01F4 01F5 01F6 01F7 01F8 01F9 01FA 01FB 01FC 01FD 01FE 01FF | 8E E0 5D B0 13 CD 10 68 00 A0 07 F7 C5 00 01 74 05 80 36 16 01 08 4D B9 FF 00 99 BE 40 01 89 CB 89 F8 F6 D3 F7 F6 E8 97 00 E8 94 00 BE 6C 04 64 02 1C 12 34 02 64 01 88 F0 10 C5 20 DE B7 30 B2 20 E8 86 00 74 21 53 B2 10 B7 14 64 2A 1C 64 2A 1C 30 ED E8 74 00 5B 74 0E B2 18 B7 1C 64 02 1C E8 67 00 74 02 E2 B3 92 80 FE 40 74 2A 9C 58 9E 7A 21 84 C9 74 04 FE C6 75 04 B0 FF EB 1D 20 D8 30 F0 30 DA 20 F2 C0 E0 02 80 E2 01 0F 45 C1 B4 FF 28 C4 88 E0 EB 04 F6 D4 20 E0 FC D4 12 B0 10 D5 01 85 FF 7A 01 40 AA 0F 85 6B FF C7 04 11 37 64 C7 44 E4 01 17 B4 09 BA F7 01 CD 21 E9 4B FF 92 29 E8 0F AF C3 05 7F 06 C3 50 F6 C3 40 75 1B 38 FC 73 17 38 D4 72 13 F6 C3 78 75 0C 84 ED 75 05 A8 78 75 04 FD 80 C4 18 30 EC F6 C6 10 75 02 00 C6 08 F4 9E 58 C3 6D 65 67 61 70 6F 6C 65 24 | mov fs, ax pop bp mov al, 13h ; = 19 int 10h ; = 16 push A000h ; = 40960 pop es test bp, 0100h ; = 256 jz 0116h ; = 7 xor 278, 08h ; = 8 dec bp mov cx, 00FFh ; = 255 cwd mov si, 0140h ; = 320 mov bx, cx mov ax, di not bl div si db E8h ; 'Φ' db 97h ; 'ù' db 00h ; ' ' db E8h ; 'Φ' db 94h ; 'ö' db 00h ; ' ' db BEh ; '╛' db 6Ch ; 'l' db 04h ; '♦' db 64h ; 'd' db 02h ; '☻' db 1Ch ; '∟' db 12h ; '↕' db 34h ; '4' db 02h ; '☻' db 64h ; 'd' db 01h ; '☺' db 88h ; 'ê' db F0h ; '≡' db 10h ; '►' db C5h ; '┼' db 20h ; ' ' db DEh ; '▐' db B7h ; '╖' db 30h ; '0' db B2h ; '▓' db 20h ; ' ' db E8h ; 'Φ' db 86h ; 'å' db 00h ; ' ' db 74h ; 't' db 21h ; '!' db 53h ; 'S' db B2h ; '▓' db 10h ; '►' db B7h ; '╖' db 14h ; '¶' db 64h ; 'd' db 2Ah ; '*' db 1Ch ; '∟' db 64h ; 'd' db 2Ah ; '*' db 1Ch ; '∟' db 30h ; '0' db EDh ; 'φ' db E8h ; 'Φ' db 74h ; 't' db 00h ; ' ' db 5Bh ; '[' db 74h ; 't' db 0Eh ; '♫' db B2h ; '▓' db 18h ; '↑' db B7h ; '╖' db 1Ch ; '∟' db 64h ; 'd' db 02h ; '☻' db 1Ch ; '∟' db E8h ; 'Φ' db 67h ; 'g' db 00h ; ' ' db 74h ; 't' db 02h ; '☻' db E2h ; 'Γ' db B3h ; '│' db 92h ; 'Æ' db 80h ; 'Ç' db FEh ; '■' db 40h ; '@' db 74h ; 't' db 2Ah ; '*' db 9Ch ; '£' db 58h ; 'X' db 9Eh ; '₧' db 7Ah ; 'z' db 21h ; '!' db 84h ; 'ä' db C9h ; '╔' db 74h ; 't' db 04h ; '♦' db FEh ; '■' db C6h ; '╞' db 75h ; 'u' db 04h ; '♦' db B0h ; '░' db FFh ; ' ' db EBh ; 'δ' db 1Dh ; '↔' db 20h ; ' ' db D8h ; '╪' db 30h ; '0' db F0h ; '≡' db 30h ; '0' db DAh ; '┌' db 20h ; ' ' db F2h ; '≥' db C0h ; '└' db E0h ; 'α' db 02h ; '☻' db 80h ; 'Ç' db E2h ; 'Γ' db 01h ; '☺' db 0Fh ; '☼' db 45h ; 'E' db C1h ; '┴' db B4h ; '┤' db FFh ; ' ' db 28h ; '(' db C4h ; '─' db 88h ; 'ê' db E0h ; 'α' db EBh ; 'δ' db 04h ; '♦' db F6h ; '÷' db D4h ; '╘' db 20h ; ' ' db E0h ; 'α' db FCh ; 'ⁿ' db D4h ; '╘' db 12h ; '↕' db B0h ; '░' db 10h ; '►' db D5h ; '╒' db 01h ; '☺' db 85h ; 'à' db FFh ; ' ' db 7Ah ; 'z' db 01h ; '☺' db 40h ; '@' db AAh ; '¬' db 0Fh ; '☼' db 85h ; 'à' db 6Bh ; 'k' db FFh ; ' ' db C7h ; '╟' db 04h ; '♦' db 11h ; '◄' db 37h ; '7' db 64h ; 'd' db C7h ; '╟' db 44h ; 'D' db E4h ; 'Σ' db 01h ; '☺' db 17h ; '↨' db B4h ; '┤' db 09h ; '○' db BAh ; '║' db F7h ; '≈' db 01h ; '☺' db CDh ; '═' db 21h ; '!' db E9h ; 'Θ' db 4Bh ; 'K' db FFh ; ' ' db 92h ; 'Æ' db 29h ; ')' db E8h ; 'Φ' db 0Fh ; '☼' db AFh ; '»' db C3h ; '├' db 05h ; '♣' db 7Fh ; '⌂' db 06h ; '♠' db C3h ; '├' db 50h ; 'P' db F6h ; '÷' db C3h ; '├' db 40h ; '@' db 75h ; 'u' db 1Bh ; '←' db 38h ; '8' db FCh ; 'ⁿ' db 73h ; 's' db 17h ; '↨' db 38h ; '8' db D4h ; '╘' db 72h ; 'r' db 13h ; '‼' db F6h ; '÷' db C3h ; '├' db 78h ; 'x' db 75h ; 'u' db 0Ch ; '♀' db 84h ; 'ä' db EDh ; 'φ' db 75h ; 'u' db 05h ; '♣' db A8h ; '¿' db 78h ; 'x' db 75h ; 'u' db 04h ; '♦' db FDh ; '²' db 80h ; 'Ç' db C4h ; '─' db 18h ; '↑' db 30h ; '0' db ECh ; '∞' db F6h ; '÷' db C6h ; '╞' db 10h ; '►' db 75h ; 'u' db 02h ; '☻' db 00h ; ' ' db C6h ; '╞' db 08h ; '◘' db F4h ; '⌠' db 9Eh ; '₧' db 58h ; 'X' db C3h ; '├' db 6Dh ; 'm' db 65h ; 'e' db 67h ; 'g' db 61h ; 'a' db 70h ; 'p' db 6Fh ; 'o' db 6Ch ; 'l' db 65h ; 'e' db 24h ; '$' | mov fs,ax ; ax=0? was pop bp before rewrite for non-zero fs seg pop bp ; bp=0 cs:[0fffeh]=ss:[sp]=0000 if not debug executed mov al,13h ; function switch to video mode 13h 320x200x256 & cls int 10h ; general video bios service for all mode 13h vga api push w 0a000h ; was les cx,[bx] es=9fffh cx=20cdh & lea ax,[di-10h] pop es ; ms-dos v6.22 or freedos not "les rr,[0]" compatible a:test bp,100h ; script idx bounds reached? bp E [0;255] i.e aam 255 jz c ; if hibyte OR rollover sign propagated to hibyte lsb xor b[c],8h ; xor mutex modify next opcode to keep idx normalized c:dec bp ; follow through and advance script idx dec bp/inc bp e:mov cx,0ffh ; cl=visibility fostrum, null ch implicit object mask g:cwd ; shorter xor dx,dx with ah<128 for div moved for agi mov si,140h ; vga vid mode 19 horizontal scanline width in pixels mov bx,cx ; bl=distance nullify bh raymarch object height limit mov ax,di ; di=beam spot absolute vga coord, no dos para fix-up not bl ; bl=distance/z axis orientation= -visibility fostrum div si ; main 3d projection returns with ax=y dx=x ; dh = x call q ; main 3d projection returns withah=(y-y0)*z ; bl = z call q ; main 3d projection returns withah=(x-x0)*z ; ah = y mov si,46ch ; 46ch=bda rtc off in zero seg plus ad hoc off buffer add bl,[fs:si] ; bl=z+=rtc word in bda advances camera, assumed fs=0 adc dh,[si] ; dh+=beam spot camera x coordinates cs/ds:46ch & rtc add ah,[si+1] ; ah+=beam spot camera y coordinates cs/ds:46dh & rtc mov al,dh ; push/pop preserve texture x>>8 texel base for later adc ch,al ; this object's implicit form xor /w building overlay and dh,bl ; dh=x bl=x i.e x+=y bh and dl used as generic params mov bh,30h ; bh=y height max of overpass, function generic param mov dl,20h ; dl=y height min of overpass, function generic param call r ; function returns if this object or building ray hit jz h ; if objects volume intersect with ray texture former push bx ; preserve prev rtc time to avoid costly seg override mov dl,10h ; dl=y height max of spaceship function generic param mov bh,14h ; bh=y height min of spaceship function generic param sub bl,[fs:si] ; bl=z+=rtc word in bda advances spaceship1 camera<-- sub bl,[fs:si] ; bl=z+=rtc word in bda advances spaceship1 camera<-- xor ch,ch ; flag differenciates between spaceship* and overpass call r ; function returns if this object or building ray hit pop bx ; restore prev rtc time also implicit ch val returned jz h ; if objects volume intersect with ray texture former mov dl,18h ; dl=y height max of spaceship function generic param mov bh,1ch ; bh=y height min of spaceship function generic param add bl,[fs:si] ; bl=z+=rtc word in bda advances spaceship2 camera--> call r ; function returns if this object or building ray hit jz h ; if objects volume intersect with ray texture former loop g ; if no object volumes intersect then continue z rays h:xchg ax,dx ; texture subroutine - clone ray collision height val cmp dh,40h ; test if this ray collision height val is exactly 64 jz l ; process as scenery bottom floor, al=depth was saved pushf ; ax disposed of in z-buffer order override data flow pop ax ; subroutine marked eflags /w bit10 df=spaceship true sahf ; convert this object's bit10 df to pf for conditions jp k ; if z-ray collided with a spaceship object then exit test cl,cl ; else test if ray collision exited on loop condition jz i ; if distance=0=>no scenery intersection=open horizon inc dh ; test if this ray collision height=top=255=sky limit jnz j ; else ray hit other scenery building/overpass object i:mov al,0ffh ; is sky so apply old b/w film rear projection effect jmp m ; with brightest standard vga palette grayscale color j:and al,bl ; is building/overpass process texel window step #1/3 xor al,dh ; is building/overpass process texel window step #2/3 xor dl,bl ; is building/overpass process texel bricks step #1/2 and dl,dh ; is building/overpass process texel bricks step #2/2 shl al,02h ; is building/overpass process texel window step #3/3 and dl,01h ; test for building/overpass window or bricks texture cmovnz ax,cx ; if window texel then color val=distance 586+ opcode mov ah,0ffh ; colour for window or bricks of building or overpass sub ah,al ; is dynamic for windows and static for all other obj k:mov al,ah ; thunk for building/overpass/window/bricks/spaceship jmp m ; proceed to last step of grayscale color normalizing l:not ah ; floor grey bicolor flat-shaded for building shadows and al,ah ; floor color multiplexes shadow depth=k*(255-height) m:cld ; common thunk nullifies next spaceship=true obj flag aam 12h ; normalize with dithering add overlap ah=color/18+00 mov al,16 ; normalize with dithering add overlap ah=color/18+16 aad 1 ; dithering normalized and prepare for next frame cwd test di,di ; test for all pixels plotted overrunning vga segment jp o ; preserve zf flag and test if absolute beam position inc ax ; parity even augmenting lighting for odd meta-pixels o:stosb ; write screen pixel & advance absolute beam position jnz e ; if dst idx then continue automatic vga wrap-up fill mov w[si],3711h ; post-assigns camera fixed value coordinates (17,55) mov w[fs:si-1ch],1701h ; bda mem vid page 0 title curs position col=1 row=24 mov ah,9 ; dos 1+ write $ terminated string to standard output mov dx,p ; hardcoded 24h terminated ascii string of demo title int 21h ; general ms-dos api /w function 9 print ds:dx string jmp a ; process next demo frame (sorry no escape sequence!) q:xchg ax,dx ; 3-axis rotations require 2-axis ah=dh=x dh=(y-y0)*z sub ax,bp ; translate to demo script idx arbitrary origin bp,bp imul ax,bx ; project abcsisses/ordinates ah=(x-x0)*z dh=(y-y0)*z add ax,67fh ; translate back to ~center=k*sqr(2) arbitrary fix-up ret ; --------------------------->return to caller (0c3h) r:push ax ; isosurface discrimination preserve building overlay test bl,40h ; is it time~depth (i.e z+rtc) displaying an overpass jnz v ; if not then process default buildings intersections cmp ah,bh ; is y height>min of spaceship/overpass generic param jnc v ; if not then process default buildings intersections cmp ah,dl ; is y height<max of spaceship/overpass generic param jc v ; if not then process default buildings intersections test bl,78h ; is spaceship/overpass 120<z depth<128 static params jnz u ; if not then process modified building intersections test ch,ch ; flag differenciates between spaceship* and overpass jnz t ; if overpass then proceed to translate it vertically test al,78h ; is spaceship only objects 120<x width<128 in static jnz u ; if not then process modified building intersections std ; is spaceship and visible so set df flag accordingly t:add ah,18h ; translate spaceship/overpass objects vertically +24 u:xor ah,ch ; this object's implicit form xor /w building overlay v:test dh,10h ; alternate scene vertical irregularity every step 16 jnz x ; i.e : _||_||_||_||_||_||_||_||_||_||_||_||_||_||_|| add dh,al ; reduce scene horizontally = strech scene vertically x:or ah,dh ; induce scene horizontal "y-colinear" irregularities sahf ; implicit isosurface volume x AND y AND z AND 64=64? pop ax ; isosurface discrimination preserve building overlay ret ; --------------------------->return to caller (0c3h) p db "megapole$" ; hardcoded 24h terminated ascii string of demo title b equ byte w equ word |