計(jì)算機(jī)圖形學(xué)實(shí)驗(yàn)三：圓的生成算法的實(shí)現(xiàn)

實(shí)驗(yàn)三：圓的生成算法的實(shí)現(xiàn)班級(jí)08信計(jì)學(xué)號(hào)20080502069姓名分?jǐn)?shù)一、實(shí)驗(yàn)?zāi)康暮鸵?、理解圓的基本原理。2、掌握幾種常見的圓生成算法。3、利用TurboC實(shí)現(xiàn)圓生成的中點(diǎn)畫圓算法。4、理解圓生成的基本原理，掌握幾種常見的圓生成算法。5、利用VisualC++實(shí)現(xiàn)圓生成的中點(diǎn)畫圓的算法。6、利用VisualC++實(shí)現(xiàn)圓的Bresenham算法。7、簡(jiǎn)單了解其他算法。二、實(shí)驗(yàn)內(nèi)容：1.利用中點(diǎn)畫圖算法，在屏幕上生成任意一段圓弧。2.利用圖的對(duì)稱性，將(1)題生成的圓弧擴(kuò)展為一個(gè)整圓。3.利用bresebham算法設(shè)計(jì)出一段圓弧。三、實(shí)驗(yàn)步驟：1.預(yù)習(xí)教材關(guān)于圓的生成原理。2.仿照教材關(guān)于圓生成的中點(diǎn)畫圓算法和bresenham算法，使用C++實(shí)現(xiàn)該算法。3.調(diào)試、編譯、運(yùn)行程序。四、實(shí)驗(yàn)結(jié)果分析：1.這里用圓生成的中點(diǎn)畫圓算法為例來繪制一個(gè)圓。程序代碼：#include<graphics.h>#include<conio.h>voidcirclepoints(intx,inty,intcolor){ intm,n; floatxasp,yasp; floataspectratio; m=200; n=200; getaspectratio(&xasp,&yasp); aspectratio=xasp/yasp; putpixel(x+m,y*aspectratio+n,color); putpixel(y+m,x*aspectratio+n,color); putpixel(-y+m,x*aspectratio+n,color); putpixel(-x+m,y*aspectratio+n,color); putpixel(y+m,-x*aspectratio+n,color);putpixel(x+m,-y*aspectratio+n,color);putpixel(-x+m,-y*aspectratio+n,color); putpixel(-y+m,-x*aspectratio+n,color);}voidmidpointcircle(intr,intc){ intx,y; floatd; x=0;y=r;d=5.0/4-r; circlepoints(x,y,c); while(y>x) { if(d<=0) d+=2.0*x+3; else { d+=2.0*(x-y)+5; y--; } x++; circlepoints(x,y,c); }}voidmain(){ inta,b; intgraphdriver=DETECT; intgraphmode=0; initgraph(&graphdriver,&graphmode,""); cleardevice(); a=200;b=200; midpointcircle(a,b); getch(); closegraph();}運(yùn)行結(jié)果:2.利用bresenham算法生成圓的代碼：#include<graphics.h>#include<stdio.h>#include<conio.h>voidBresenhemCircle(intcenterx,intcentery,intradius,intcolor,inttype);voidmain(){intdrive=DETECT,mode;inti,j;initgraph(&drive,&mode,"");BresenhemCircle(300,200,100,150,0);getch();closegraph();}voidBresenhemCircle(intcenterx,intcentery,intradius,intcolor,inttype){intx=type=0;/*初始橫坐標(biāo)為原點(diǎn)*/inty=radius;/*初始縱坐標(biāo)遠(yuǎn)離原點(diǎn)*/intdelta=2*(1-radius);intdirection;while(y>=0){getch();if(!type)/*執(zhí)行*/{/*在上半圓畫兩點(diǎn)*/putpixel(centerx+x,centery+y,color);putpixel(centerx-x,centery+y,color);/*在下半圓畫兩點(diǎn)*/putpixel(centerx-x,centery-y,color);putpixel(centerx+x,centery-y,color);getch();}else{line(centerx+x,centery+y,centerx+x,centery-y);line(centerx-x,centery+y,centerx-x,centery-y);getch();}if(delta<0){if((2*(delta+y)-1)<0)direction=1;elsedirection=2;}elseif(delta>0){if((2*(delta-x)-1)>0)direction=3;elsedirection=2;}elsedirection=2;switch(direction){case1:x++;delta+=(2*x+1);break;case2:x++;y--;delt