这个程序是巧妙的利用了坐标的不断变化

1、;这个程序是巧妙的利用了坐标的不断变化，从而实现了由星星构成的箱子3D转动！;编译方法： 1 tasm 3d.asm;           2 tlink 3d.obj;           3 exe2bin 3d.exe ;   Assembler Program By Vulture.       &#

2、160;                                      ;   3D-system example. Use the following formulas to rotate a p

3、oint:           ;        Rotate around x-axis                            &#

4、160;                     ;        YT = Y * COS(xang) - Z * SIN(xang) / 256               &

5、#160;              ;        ZT = Y * SIN(xang) + Z * COS(xang) / 256                      

6、        ;        Y = YT                                  

7、60;                             ;        Z = ZT             

8、                                                  

9、 ;                                                 

10、0;                            ;        Rotate around y-axis            

11、;                                      ;        XT = X * COS(yang) - Z * SIN(yan

12、g) / 256                              ;        ZT = X * SIN(yang) + Z * COS(yang) / 256     

13、60;                        ;        X = XT                  

14、                                              ;    

15、0;   Z = ZT                                              

16、60;                 ;        Rotate around z-axis                      

17、0;                           ;        XT = X * COS(zang) - Y * SIN(zang) / 256         

18、60;                    ;        YT = X * SIN(zang) + Y * COS(zang) / 256                &#

19、160;             ;        X = XT                             

20、;                                   ;        Y = YT       &#

21、160;                                                 &#

22、160;      ;   Divide by 256 coz we have multiplyd our sin values with 256 too.           ;   This example isn't too fast right now but it'll work just fine.       

23、;     ;       Current Date: 6-9-95         Vulture                          

24、0;        ;IDEAL                           ; Ideal modeP386            

25、0;               ; Allow 80386 instructionsJUMPS                           ; Tasm handles out of ran

26、ge jumps (rulez!:)  SEGMENT CODE                    ; Code segment startsASSUME cs:code,ds:code          ; Let cs and ds point to code segment ORG 100

27、h                        ; Make a .COM file START:                     

28、0;    ; Main program     mov     ax,0013h            ; Init vga    int     10h    mov     ax,cs    mov

29、60;    ds,ax               ; ds points to codesegment    mov     ax,0a000h    mov     es,ax         

30、      ; es points to vga    lea     si,Palette        ; Set palette    mov     dx,3c8h    xor     al,al    out 

31、0;   dx,al    mov     dx,3c9h    mov     cx,189*3    repz    outsb; = Set some variables =    mov     DeltaX,1       

32、60;  ; Initial speed of rotation    mov     DeltaY,1          ; Change this and watch what    mov     DeltaZ,1          ; happens. It&#

33、39;s fun!    mov     Xoff,256    mov     Yoff,256          ; Used for calculating vga-pos    mov     Zoff,300       

34、;   ; Distance from viewerMainLoop:    call    MainProgram         ; Yep. do it all. ;-)    in      al,60h            &#

35、160; ; Scan keyboard    cmp     al,1                ; Test on ESCAPE    jne     MainLoop           

36、; Continue if not keypressed; = Quit to DOS =    mov     ax,0003h            ; Back to textmode    int     10h    lea     dx,Credits &#

37、160;  mov     ah,9    int     21h    mov     ax,4c00h            ; Return control to DOS    int     21h  

38、               ; Call DOS interrupt; = Sub-routines =           PROC WaitVrt                 &#

39、160;  ; Waits for vertical retrace to reduce "snow"    mov     dx,3dahVrt:    in      al,dx    test    al,8    jnz     Vrt    

40、;             ; Wait until Verticle Retrace startsNoVrt:    in      al,dx    test    al,8    jz      NoVrt    

41、           ; Wait until Verticle Retrace ends    ret                         ; Return to main programENDP WaitVrtPR

42、OC UpdateAngles; Calculates new x,y,z angles; to rotate around    mov     ax,XAngle         ; Load current angles    mov     bx,YAngle    mov     cx,ZAngle

43、               add     ax,DeltaX         ; Add velocity    and     ax,11111111b        ; Range from 0.255

44、    mov     XAngle,ax         ; Update X    add     bx,DeltaY         ; Add velocity    and     bx,11111111b &

45、#160;      ; Range from 0.255    mov     YAngle,bx         ; Update Y    add     cx,DeltaZ         ; Add velocity  

46、  and     cx,11111111b        ; Range from 0.255    mov     ZAngle,cx         ; Update Z    retENDP UpdateAnglesPROC GetSinCos; Needed : bx=angle (0.2

47、55); Returns: ax=Sin   bx=Cos    push    bx                  ; Save angle (use as pointer)    shl     bx,1     

48、0;          ; Grab a word so bx=bx*2    mov     ax,SinCos + bx    ; Get sine    pop     bx             &#

49、160;    ; Restore pointer into bx    push    ax                  ; Save sine on stack    add     bx,64     

50、60;         ; Add 64 to get cosine    and     bx,11111111b        ; Range from 0.255    shl     bx,1         &

51、#160;      ; *2 coz it's a word    mov     ax,SinCos + bx    ; Get cosine    mov     bx,ax               ; Save it&#

52、160;  bx=Cos    pop     ax                  ; Restore   ax=Sin    retENDP GetSinCosPROC SetRotation; Set sine & cosine of x,y,z   

53、mov     bx,XAngle         ; Grab angle    call    GetSinCos           ; Get the sine&cosine    mov     Xsin,ax  

54、;         ; Save sin    mov     Xcos,bx           ; Save cos    mov     bx,Yangle    call    GetSinCos &#

55、160;  mov     Ysin,ax    mov     Ycos,bx    mov     bx,Zangle    call    GetSinCos    mov     Zsin,ax    mov   

56、;  Zcos,bx    retENDP SetRotationPROC RotatePoint            ; Rotates the point around x,y,z; Gets original x,y,z values; This can be done elsewhere    movsx   ax,Cube+si    ; si = X&#

57、160;       (movsx coz of byte)    mov     X,ax    movsx   ax,Cube+si+1  ; si+1 = Y    mov     Y,ax    movsx   ax,Cube+si+2  ; si+2 = Z 

58、   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    mov     bx,XCos    imul 

59、;   bx               ; ax = Y * Cos(xang)    mov     bp,ax    mov     ax,Z    mov     bx,XSin    imu

60、l    bx               ; ax = Z * Sin(xang)    sub     bp,ax            ; bp = Y * Cos(xang) - Z * Sin(xang)   

61、 sar     bp,8             ; bp = Y * Cos(xang) - Z * Sin(xang) / 256    mov     Yt,bp    mov     ax,Y    mov     bx

62、,XSin    imul    bx               ; ax = Y * Sin(xang)    mov     bp,ax    mov     ax,Z    mov   

63、60; bx,XCos    imul    bx               ; ax = Z * Cos(xang)    add     bp,ax            ; bp = Y * SIN(xang)

64、+ Z * COS(xang)    sar     bp,8             ; bp = Y * SIN(xang) + Z * COS(xang) / 256    mov     Zt,bp    mov     ax,Yt  

65、60;       ; 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 *

66、COS(yang) / 256; X = XT; Z = ZT    mov     ax,X    mov     bx,YCos    imul    bx               ; ax = X * Cos(yang)  

67、60; mov     bp,ax    mov     ax,Z    mov     bx,YSin    imul    bx               ; ax = Z * Sin(yang) 

68、60;  sub     bp,ax            ; bp = X * Cos(yang) - Z * Sin(yang)    sar     bp,8             ; bp = X * Cos(yang) - Z * Sin

69、(yang) / 256    mov     Xt,bp    mov     ax,X    mov     bx,YSin    imul    bx               ;

70、ax = X * Sin(yang)    mov     bp,ax    mov     ax,Z    mov     bx,YCos    imul    bx             

71、60; ; ax = Z * Cos(yang)    add     bp,ax            ; bp = X * SIN(yang) + Z * COS(yang)    sar     bp,8           

72、0; ; bp = X * SIN(yang) + Z * COS(yang) / 256    mov     Zt,bp    mov     ax,Xt          ; Switch values    mov     X,ax    mov &#

73、160;   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    mov     bx,ZCos

74、    imul    bx               ; ax = X * Cos(zang)    mov     bp,ax    mov     ax,Y    mov     b

75、x,ZSin    imul    bx               ; ax = Y * Sin(zang)    sub     bp,ax            ; bp = X * Cos(zang) - Y *

76、 Sin(zang)    sar     bp,8             ; bp = X * Cos(zang) - Y * Sin(zang) / 256    mov     Xt,bp    mov     ax,X    mo

77、v     bx,ZSin    imul    bx               ; ax = X * Sin(zang)    mov     bp,ax    mov     ax,Y  

78、60; mov     bx,ZCos    imul    bx               ; ax = Y * Cos(zang)    add     bp,ax          

79、  ; bp = X * SIN(zang) + Y * COS(zang)    sar     bp,8             ; bp = X * SIN(zang) + Y * COS(zang) / 256    mov     Yt,bp    mov   

80、;  ax,Xt          ; Switch values    mov     X,ax    mov     ax,Yt    mov     Y,ax    retENDP RotatePoint    &

81、#160;      PROC ShowPoint; Calculates screenposition and; plots the point on the screen    mov     ax,Xoff           ; Xoff*X / Z+Zoff = screen x    mov    

82、; bx,X    imul    bx    mov     bx,Z    add     bx,Zoff           ; Distance    idiv    bx    add &#

83、160;   ax,Mx             ; Center on screen    mov     bp,ax    mov     ax,Yoff           ; Yoff*Y / Z+Zoff =

84、screen y    mov     bx,Y    imul    bx    mov     bx,Z    add     bx,Zoff           ; Distance    id

85、iv    bx    add     ax,My             ; Center on screen               mov     bx,320    i

86、mul    bx    add     ax,bp               ; ax = (y*320)+x    mov     di,ax    mov     ax,Z   &#

87、160;          ; Get color from Z    add     ax,100d             ; (This piece of code could be improved)    mov     byte ptr

88、es:di,al ; Place a dot with color al    mov     Erase+si,di       ; Save position for erase    retENDP ShowPointPROC MainProgram    call    UpdateAngles      &#

89、160; ; Calculate new angles    call    SetRotation         ; Find sine & cosine of those angles    xor     si,si             &

90、#160; ; First 3d-point    mov     cx,MaxPointsShowLoop:      call    RotatePoint         ; Rotates the point using above formulas    call    ShowPoint 

91、0;         ; Shows the point    add     si,3                ; Next 3d-point    loop    ShowLoop    call&#

92、160;   WaitVrt             ; Wait for retrace    xor     si,si               ; Starting with point 0    xor

93、60;    al,al               ; Color = 0 = black    mov     cx,MaxPointsDeletion:    mov     di,Erase+si       ; di =

94、 vgapos old point    mov     byte ptr es:di,al ; Delete it    add     si,3                ; Next point    loop    Deletion

95、60;   retENDP MainProgram; = DATA =           Credits   DB   13,10,"Code by Vulture / Outlaw Triad",13,10,"$"Label SinCos Word       ; 256 valuesdw 0,6,13,19,25,31,38,44,

96、50,56dw 62,68,74,80,86,92,98,104,109,115dw 121,126,132,137,142,147,152,157,162,167dw 172,177,181,185,190,194,198,202,206,209dw 213,216,220,223,226,229,231,234,237,239dw 241,243,245,247,248,250,251,252,253,254dw 255,255,256,256,256,256,256,255,255,254dw 253,252,251,250,248,247,245,243,241,239dw 237,2

97、34,231,229,226,223,220,216,213,209dw 206,202,198,194,190,185,181,177,172,167dw 162,157,152,147,142,137,132,126,121,115dw 109,104,98,92,86,80,74,68,62,56dw 50,44,38,31,25,19,13,6,0,-6dw -13,-19,-25,-31,-38,-44,-50,-56,-62,-68dw -74,-80,-86,-92,-98,-104,-109,-115,-121,-126dw -132,-137,-142,-147,-152,-

98、157,-162,-167,-172,-177dw -181,-185,-190,-194,-198,-202,-206,-209,-213,-216dw -220,-223,-226,-229,-231,-234,-237,-239,-241,-243dw -245,-247,-248,-250,-251,-252,-253,-254,-255,-255dw -256,-256,-256,-256,-256,-255,-255,-254,-253,-252dw -251,-250,-248,-247,-245,-243,-241,-239,-237,-234dw -231,-229,-226

99、,-223,-220,-216,-213,-209,-206,-202dw -198,-194,-190,-185,-181,-177,-172,-167,-162,-157dw -152,-147,-142,-137,-132,-126,-121,-115,-109,-104dw -98,-92,-86,-80,-74,-68,-62,-56,-50,-44dw -38,-31,-25,-19,-13,-6Label Cube Byte           ; The 3d points

100、60;      c = -35            ; 5x*5y*5z (=125) points       rept 5         b = -35         rept 5           a = -35           rept 5 &#