* * * A simple Julia routine for FPU * © 1993 Erik H. Bakke/Bakke SoftDev * Some auxillary code by PC PAY/Digital Surface * * * This routine is intended as illustration only. * If you use it in your own programs, give us credit * for it, and let us know. (We like to keep track of how * our sources spread) * * * The Julia subroutine is © 1993 Erik H. Bakke/Bakke SoftDev * The system interface is © 1993 PC PAY/Digital Surface * * * OK, I know that this code could be more elegant, but I don't * have the time to do anything about it right now... (So they all * say) * * include "startup.i" ;startup code for Workbench include "libraries/exec_lib.i" ;Exec library _LVO's include "libraries/intuition_lib.i" ;Intution... include "libraries/graphics_lib.i" ;Graphics... include "intuition/intuition.i" ;Intuition related stuff include "intuition/screens.i" ;Intuition screen stuff Width=704 ;Width of fractal Height=1128 ;Height of fractal Depth=8 ;Bitplanes used for display Colors=256 ;Colors used for display DisplayID=DBLPALHIRESLACE_KEY ;Screenmode used for display Init: move.l $4.w,a6 ;Get execbase moveq #36,d0 ;Library version we want lea (GfxName,pc),a1 ;Name of library jsr (_LVOOpenLibrary,a6) ;Open library move.l d0,GfxBase ;Save library base beq.w GfxError ;Exit if error moveq #36,d0 lea (IntName,pc),a1 jsr (_LVOOpenLibrary,a6) move.l d0,a6 move.l d0,IntBase beq.w IntError lea $0.w,a0 ;Newscreen structure lea (ScrAttrs,pc),a1 ;Taglist for screen jsr (_LVOOpenScreenTagList,a6) ;Open screen move.l d0,Scr ;Save pointer beq.w ScrError ;Exit if error lea $0.w,a0 ;Newwindow structure lea (WinAttrs,pc),a1 ;Taglist for window jsr (_LVOOpenWindowTagList,a6) ;Open window move.l d0,Win ;Save pointer beq.w WinError ;Exit if error move.l d0,a0 ;Get window pointer move.l (wd_RPort,a0),a5 ;Get rastport pointer move.l (GfxBase,pc),a6 ;Get graphics base move.l (Scr,pc),a0 ;Get screen pointer add.l #sc_ViewPort,a0 ;Get viewport pointer lea (Cols,pc),a1 ;Colormap move.l #Colors,d0 ;Number of colors jsr (_LVOLoadRGB4,a6) ;Set palette fmove.w #270,fp0 ;Find a good seed value fmove.x fp0,fp1 fmovecr.x #0,fp2 ;Calculate radians for fdiv.w #180,fp2 ;the trigonometric that fadd.x fp2,fp2 ;follows fmul.x fp2,fp0 fmul.x fp2,fp1 fsin.x fp0 ;Get a good starting spot fcos.x fp1 fdiv.w #300,fp0 fdiv.w #300,fp1 fmul.w #190,fp0 fmul.w #190,fp1 fmove.x fp0,q fmove.x fp1,p bsr Julia ;Draw julia fractal m: btst #$2,$dff016 ;Wait for right mouse button bne m move.l (IntBase,pc),a6 ;Get intuition base move.l (Win,pc),a0 ;Get window pointer jsr (_LVOCloseWindow,a6) ;Close window WinError: move.l (Scr,pc),a0 ;Get screen pointer jsr (_LVOCloseScreen,a6) ;Close screen ScrError: move.l a6,a1 ;Get library pointer move.l $4.w,a6 ;Get execbase jsr (_LVOCloseLibrary,a6) ;Close library IntError: move.l (GfxBase,pc),a1 ;Get library pointer jsr (_LVOCloseLibrary,a6) ;Close library GfxError: rts ;Exit Julia: fmove.l #10000000,fp7 ;Provide some decimal places fmove.l #12000000,fp0 ;xmax=1.2 fdiv.x fp7,fp0 fmove.l #-12000000,fp1 ;xmin=-1.2 fdiv.x fp7,fp1 fmove.l #12000000,fp2 ;ymax=1.2 fdiv.x fp7,fp2 fmove.l #-12000000,fp3 ;ymin=-1.2 fdiv.x fp7,fp3 fmove.x (q,pc),fp5 ;Get q and p fmove.x (p,pc),fp4 move.l #Width,d0 move.l #Height,d1 fmove.x fp2,ymax ;Save ymax fsub.x fp1,fp0 ;get horizontal steprate fdiv.l d0,fp0 ; dx=(xmax-xmin)/width fsub.x fp3,fp2 ;get vertical steprate fdiv.l d1,fp2 ; dy=(ymax-ymin)/height fmove.x fp5,fp3 ;Get q fmove.x fp0,xdelta ;save deltas fmove.x fp2,ydelta move.w #Height/2,d4 ;Preload this one... moveq #-$1,d7 ; .nextx addq.w #$1,d7 ; cmp.w #Width/2+1,d7 ; for x=0 to 321 beq.w .exit moveq #-$1,d6 ; .nexty addq.w #$1,d6 ; cmp.w #Height,d6 ; for y=0 to 256 beq.b .nextx fmove.w d7,fp7 ; fmul.x (xdelta,pc),fp7 ; x=xc*dx+xmin fmove.w d6,fp6 ; fmul.x (ydelta,pc),fp6 ; fadd.x fp1,fp7 ; y=ymax-yc*dy fmove.x (ymax,pc),fp0 ; fsub.x fp6,fp0 fmove.w #$0,fp6 ;x²=0 fmove.x fp6,fp5 ;y²=0 move.w #255,d5 ;256 iterations moveq #$4,d3 ;preload this one too... .iter fmove.x fp6,fp2 ; fadd.x fp5,fp2 ;if (x²+y²>4) then fcmp.w d3,fp2 fbgt.w .growed fmove.x fp7,fp6 ; fmul.x fp6,fp6 ;x²=x*x fmove.x fp0,fp5 ; fmul.x fp7,fp0 ;y=2x*y+p fmul.x fp5,fp5 ; fadd.x fp0,fp0 ; fadd.x fp4,fp0 ; fmove.x fp6,fp7 ;x=x+q-y fadd.x fp3,fp7 ; fsub.x fp5,fp7 dbf d5,.iter .growed move.w d6,d1 ;get x move.w d7,d0 ;get y neg.w d5 add.w #256,d5 move.w d5,d2 ;get color ext.l d2 ;remove unwanted data bsr.w PlotPoint ;Plot this point move.w d6,d1 ;get x move.w d7,d0 ;get y sub.w #Width/2,d0 ; neg.w d0 ;the julia fractal is symmetrical add.w #Width/2,d0 ; sub.w d4,d1 ; neg.w d1 ; add.w d4,d1 ; move.w d5,d2 ;get color ext.l d2 ;remove unwanted data bsr.w PlotPoint ;Plot this point btst #$2,$dff016 beq .exit bra.w .nexty ;loop y-count .exit rts ;exit ymax: dc.x 0 ;some variables xdelta: dc.x 0 ydelta: dc.x 0 x: dc.x 0 y: dc.x 0 q: dc.x 0 p: dc.x 0 * * d0=x d1=y d2=c * PlotPoint: movem.l d0-d1,-(sp) ;store important registers move.l (GfxBase,pc),a6 ;get graphics library move.l a5,a1 ;Get rastport move.l d2,d0 ;Get color jsr (_LVOSetAPen,a6) ;Set pen color movem.l (sp)+,d0-d1 ;restore important registers move.l a5,a1 ;Get rastport jsr (_LVOWritePixel,a6) ;Write pixel rts ;Return *----------------------------------------------------------------------------- ScrAttrs: ;Taglist for screen dc.l SA_Width,Width ;Screen width dc.l SA_Height,Height ;Screen height dc.l SA_Depth,Depth ;Screen depth dc.l SA_Type,CUSTOMSCREEN ;Screen type dc.l SA_DisplayID,DisplayID ;Screen display mode dc.l TAG_END,0 ;End of taglist *----------------------------------------------------------------------------- WinAttrs: dc.l WA_Width,Width ;Window width dc.l WA_Height,Height ;Window height dc.l WA_Flags,WFLG_BORDERLESS ;Window flags dc.l WA_CustomScreen ;Window screen pointer Scr: dc.l 0 dc.l TAG_END,0 ;End of taglist *----------------------------------------------------------------------------- Cols: dc.w $000,$111,$222,$333,$444,$555,$666,$777 ;colormap dc.w $888,$999,$aaa,$bbb,$ccc,$ddd,$eee,$fff dc.w $ffe,$ffd,$ffc,$ffb,$ffa,$ff9,$ff8,$ff7 dc.w $ff6,$ff5,$ff4,$ff3,$ff2,$ff1,$ff0,$fe0 dc.w $fd0,$fc0,$fb0,$fa0,$f90,$f80,$f70,$f60 dc.w $f50,$f40,$f30,$f20,$f10,$f00,$f01,$f02 dc.w $f03,$f04,$f05,$f06,$f07,$f08,$f09,$f0a dc.w $f0b,$f0d,$f0e,$f0f,$e0f,$d0f,$c0f,$b0f dc.w $a0f,$90f,$80f,$70f,$60f,$50f,$40f,$30f dc.w $20f,$10f,$00f,$01f,$02f,$03f,$04f,$05f dc.w $06f,$07f,$08f,$09f,$0af,$0bf,$0cf,$0df dc.w $0ef,$0ff,$1ef,$2df,$3cf,$4bf,$5af,$69f dc.w $78f,$87f,$96f,$a5f,$b4f,$c3f,$d2f,$e1f dc.w $f0f,$f1f,$f2f,$f3f,$f4f,$f5f,$f6f,$f7f dc.w $f8f,$f9f,$faf,$fbf,$fcf,$fdf,$fef,$fff dc.w $eef,$ddf,$ccf,$bbf,$aaf,$99f,$88f,$77f dc.w $66f,$55f,$44f,$33f,$22f,$11f,$00f,$01e dc.w $888,$999,$aaa,$bbb,$ccc,$ddd,$eee,$fff dc.w $ffe,$ffd,$ffc,$ffb,$ffa,$ff9,$ff8,$ff7 dc.w $ff6,$ff5,$ff4,$ff3,$ff2,$ff1,$ff0,$fe0 dc.w $000,$111,$222,$333,$444,$555,$666,$777 ;The last 3 blocks dc.w $888,$999,$aaa,$bbb,$ccc,$ddd,$eee,$fff ;are repetition... dc.w $ffe,$ffd,$ffc,$ffb,$ffa,$ff9,$ff8,$ff7 dc.w $ff6,$ff5,$ff4,$ff3,$ff2,$ff1,$ff0,$fe0 dc.w $000,$111,$222,$333,$444,$555,$666,$777 dc.w $888,$999,$aaa,$bbb,$ccc,$ddd,$eee,$fff dc.w $ffe,$ffd,$ffc,$ffb,$ffa,$ff9,$ff8,$ff7 dc.w $ff6,$ff5,$ff4,$ff3,$ff2,$ff1,$ff0,$fe0 dc.w $000,$111,$222,$333,$444,$555,$666,$777 dc.w $888,$999,$aaa,$bbb,$ccc,$ddd,$eee,$fff dc.w $ffe,$ffd,$ffc,$ffb,$ffa,$ff9,$ff8,$ff7 dc.w $ff6,$ff5,$ff4,$ff3,$ff2,$ff1,$ff0,$000 *----------------------------------------------------------------------------- Win: dc.l 0 ;Window pointer IntBase: dc.l 0 ;Intuition library pointer GfxBase: dc.l 0 ;Graphics library pointer IntName: dc.b "intuition.library",0 GfxName: dc.b "graphics.library",0