旋转的3d箱子

Stack Segment Stack dw 200 dup(?) Stack Ends Code Segment ; Code segment starts Assume cs:code,ds:code ; Let cs and ds point to code segment START: ; Main program mov ax,0013h ; Init vga int 10h mov ax,cs mov ds,ax ; ds points to codesegment mov ax,0a000h mov es,ax ; es points to vga lea si,[Palette] ; Set palette mov dx,3c8h xor al,al out dx,al mov dx,3c9h mov cx,189*3 tran: mov al,byte ptr [si] out dx,al inc si loop tran mov [DeltaX],1 ; Initial speed of rotation mov [DeltaY],1 ; Change this and watch what mov [DeltaZ],1 ; happens. It's fun! mov [Xoff],256 mov [Yoff],256 ; Used for calculating vga-pos mov [Zoff],300 ; Distance from viewer MainLoop: call MainProgram ; Yep... do it all... ;-) in al,60h ; Scan keyboard cmp al,1 ; Test on ESCAPE jne MainLoop ; Continue if not keypressed ; === Quit to DOS === mov ax,0003h ; Back to textmode int 10h lea dx,[Credits] mov ah,9 int 21h mov ax,4c00h ; Return control to DOS int 21h ; Call DOS interrupt ; === Sub-routines === WaitVrt PROC ; 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 UpdateAngles PROC ; Calculates new x,y,z angles ; to rotate around mov ax,[XAngle] ; Load current angles mov bx,[YAngle] mov cx,[ZAngle] add ax,[DeltaX] ; Add velocity and ax,11111111b ; Range from 0..255 mov [XAngle],ax ; Update X add bx,[DeltaY] ; Add velocity and bx,11111111b ; Range from 0..255 mov [YAngle],bx ; Update Y add cx,[DeltaZ] ; Add velocity and cx,11111111b ; Range from 0..255 mov [ZAngle],cx ; Update Z ret UpdateAngles ENDP

GetSinCos PROC ; Needed : bx=angle (0..255) ; Returns: ax=Sin bx=Cos push bx ; Save angle (use as pointer) shl bx,1 ; Grab a word so bx=bx*2 mov ax,[SinCos + bx] ; Get sine pop bx ; Restore pointer into bx push ax ; Save sine on stack add bx,64 ; Add 64 to get cosine and bx,11111111b ; Range from 0..255 shl bx,1 ; *2 coz it's a wordmov ax,[SinCos + bx] ; Get cosine mov bx,ax ; Save it bx=Cos pop ax ; Restore ax=Sin ret GetSinCos ENDP SetRotation PROC ; Set sine & cosine of x,y,z mov bx,[XAngle] ; Grab angle call GetSinCos ; Get the sine&cosine mov [Xsin],ax ; Save sin mov [Xcos],bx ; Save cos mov bx,[Yangle] call GetSinCos mov [Ysin],ax mov [Ycos],bx mov bx,[Zangle] call GetSinCos mov [Zsin],ax mov [Zcos],bx ret SetRotation ENDP RotatePoint PROC ; Rotates the point around x,y,z ; Gets original x,y,z values ; This can be done elsewhere mov al,byte ptr [Cube+si] ; si = X (movsx coz of byte) cbw mov [X],ax mov al,byte ptr [Cube+si+1] ; si+1 = Y cbw mov [Y],ax mov al,byte ptr [Cube+si+2] ; si+2 = Z cbw mov [Z],ax ; Rotate around x-axis ; YT = Y * COS(xang) - Z * SIN(xang) / 256 ; ZT = Y * SIN(xang) + Z * COS(xang) / 256 ; Y = YT ; Z = ZT mov ax,[Y] cwd mov bx,[XCos] imul bx ; ax = Y * Cos(xang) mov
bp
,ax mov ax,[Z] cwd mov bx,[XSin] imul bx ; ax = Z * Sin(xang) sub bp,ax mov ax,bp cwd mov bx,256 ; bp = Y * Cos(xang) - Z * Sin(xang) idiv bx ; bp = Y * Cos(xang) - Z * Sin(xang) / 256 mov [Yt],ax mov ax,[Y] cwd mov bx,[XSin] imul bx ; ax = Y * Sin(xang) mov bp,ax mov ax,[Z] cwd mov bx,[XCos] imul bx ; ax = Z * Cos(xang) add bp,ax mov ax,bp cwd mov bx,256 ; bp = Y * SIN(xang) + Z * COS(xang) idiv bx ; bp = Y * SIN(xang) + Z * COS(xang) / 256 mov [Zt],ax mov ax,[Yt] ; Switch values mov [Y],ax mov ax,[Zt] mov [Z],ax

; Rotate around y-axis ; XT = X * COS(yang) - Z * SIN(yang) / 256 ; ZT = X * SIN(yang) + Z * COS(yang) / 256 ; X = XT ; Z = ZT mov ax,[X] cwd mov bx,[YCos] imul bx ; ax = X * Cos(yang) mov bp,ax mov ax,[Z] cwd mov bx,[YSin] imul bx ; ax = Z * Sin(yang) sub bp,ax mov ax,bp cwd mov bx,256 ; bp = X * Cos(yang) - Z * Sin(yang) idiv bx ; bp = X * Cos(yang) - Z * Sin(yang) / 256 mov [Xt],ax mov ax,[X] cwd mov bx,[YSin] imul bx ; ax = X * Sin(yang) mov bp,ax mov ax,[Z] cwd mov bx,[YCos] imul bx ; ax = Z * Cos(yang) add bp,ax mov ax,bp cwd mov bx,256 ; bp = X * SIN(yang) + Z * COS(yang) idiv bx ; bp = X * SIN(yang) + Z * COS(yang) / 256 mov [Zt],ax mov ax,[Xt] ; Switch values mov [X],ax mov ax,[Zt] mov [Z],ax

; Rotate around z-axis ; XT = X * COS(zang) - Y * SIN(zang) / 256 ; YT = X * SIN(zang) + Y * COS(zang) / 256 ; X = XT ; Y = YT mov ax,[X] cwd mov bx,[ZCos] imul bx ; ax = X * Cos(zang) mov bp,ax mov ax,[Y] cwd mov bx,[ZSin] imul bx ; ax = Y * Sin(zang) sub bp,ax mov ax,bp cwd mov bx,256 ; bp = X * Cos(zang) - Y * Sin(zang) idiv bx ; bp = X * Cos(zang) - Y * Sin(zang) / 256 mov [Xt],ax mov ax,[X] cwd mov bx,[ZSin] imul bx ; ax = X * Sin(zang) mov bp,ax mov ax,[Y] cwd mov bx,[ZCos] imul bx ; ax = Y * Cos(zang) add bp,ax mov ax,bp cwd mov bp,256 ; bp = X * SIN(zang) + Y * COS(zang) idiv bp ; bp = X * SIN(zang) + Y * COS(zang) / 256 mov [Yt],ax mov ax,[Xt] ; Switch values mov [X],ax mov ax,[Yt] mov [Y],ax ret RotatePoint ENDP

ShowPoint PROC ; Calculates screenposition and ; plots the point on the screen mov ax,[Xoff] ; Xoff*X / Z+Zoff = screen x cwd mov bx,[X] imul bx mov bx,[Z] add bx,[Zoff] ; Distance idiv bx add ax,[Mx] ; Center on screen mov bp,ax mov ax,[Yoff] cwd ; Yoff*Y / Z+Zoff = screen y mov bx,[Y] imul bx mov bx,[Z] add bx,[Zoff] ; Distance idiv bx add ax,[My] ; Center on screen mov bx,320 imul bx add ax,bp ; ax = (y*320)+x mov di,ax mov ax,[Z] ; Get color from Z add ax,50 ; (This piece of code could be improved) mov byte ptr es:[di],al ; Place a dot with color al mov [Erase+si],di ; Save position for erase ret ShowPoint ENDP MainProgram PROC call UpdateAngles ; Calculate new angles call SetRotation ; Find sine & cosine of those angles xor si,si ; First 3d-point mov cx,MaxPoints ShowLoop: call RotatePoint ; Rotates the point using above formulas call ShowPoint ; Shows the point add si,3 ; Next 3d-point loop ShowLoop call WaitVrt ; Wait for retrace xor si,si ; Starting with point 0 xor al,al ; Color = 0 = black mov cx,MaxPoints Deletion: mov di,[Erase+si] ; di = vgapos old point mov byte ptr es:[di],al ; Delete it add si,3 ; Next point loop Deletion ret MainProgram ENDP; === DATA === Credits DB 13,10,"Code by Vulture / Outlaw Triad",13,10,"$" SinCos Label Word ; 256 values dw 0,6,13,19,25,31,38,44,50,56 dw 62,68,74,80,86,92,98,104,109,115 dw 121,126,132,137,142,147,152,157,162,167 dw 172,177,181,185,190,194,198,202,206,209 dw 213,216,220,223,226,229,231,234,237,239 dw 241,243,245,247,248,250,251,252,253,254 dw 255,255,256,256,256,256,256,255,255,254 dw 253,252,251,250,248,247,245,243,241,239 dw 237,234,231,229,226,223,220,216,213,209 dw 206,202,198,194,190,185,181,177,172,167 dw 162,157,152,147,142,137,132,126,121,115 dw 109,104,98,92,86,80,74,68,62,56 dw 50,44,38,31,25,19,13,6,0,-6 dw -13,-19,-25,-31,-38,-44,-50,-56,-62,-68 dw -74,-80,-86,-92,-98,-104,-109,-115,-121,-126 dw -132,-137,-142,-147,-152,-157,-162,-167,-172,-177 dw -181,-185,-190,-194,-198,-202,-206,-209,-213,-216 dw -220,-223,-226,-229,-231,-234,-237,-239,-241,-243 dw -245,-247,-248,-250,-251,-252,-253,-254,-255,-255 dw -256,-256,-256,-256,-256,-255,-255,-254,-253,-252 dw -251,-250,-248,-247,-245,-243,-241,-239,-237,-234 dw -231,-229,-226,-223,-220,-216,-213,-209,-206,-202 dw -198,-194,-190,-185,-181,-177,-172,-167,-162,-157 dw -152,-147,-142,-137,-132,-126,-121,-115,-109,-104 dw -98,-92,-86,-80,-74,-68,-62,-56,-50,-44 dw -38,-31,-25,-19,-13,-6 Cube Label Byte ; The 3d points c = -35 ; 5x*5y*5z (=125) points rept 5 b = -35 rept 5 a = -35 rept 5 db a,b,c a = a + 20 endm b = b + 20 endm c = c + 20 endm Palette Label Byte ; The palette to use db 1,1,1 ; 63*3 gray-tint d = 63 rept 63 db d,d,d db d,d,d db d,d,d d = d - 1 endm X DW ? ; X variable for formula Y DW ? Z DW ? Xt DW ? ; Temporary variable for x Yt DW ? Zt DW ? XAngle DW 0 ; Angle to rotate around x YAngle DW 0 ZAngle DW 0 DeltaX DW ? ; Amound Xangle is increased each time DeltaY DW ? DeltaZ DW ? Xoff DW ? Yoff DW ? Zoff DW ? ; Distance from viewer XSin DW ? ; Sine and cosine of angle to rotate around XCos DW ? YSin DW ? YCos DW ? ZSin DW ? ZCos DW ? Mx DW 140 ; Middle of the screen My DW 80 MaxPoints EQU 125 ; Number of 3d Points Erase DW MaxPoints DUP (?) ; Array for deletion screenpoints code ENDS ; End of codesegment END START ; The definite end.... :)