Circle direct drawing algorithm

Sat Jul 21, 2012 2:22 pm

Circle direct drawing algorithm using C++ MFC

Code:: void CircleDirect(HDC hdc,int xc,int yc, int R) { int x=0,y=R; int R2=R*R; Draw8Points(hdc,xc,yc,x,y); while(x<y) { x++; y=round(sqrt((double)(R2-x*x))); Draw8Points(hdc,xc,yc,x,y); } }

Code:: void Draw8Points(HDC hdc,int xc,int yc, int a, int b) { SetPixel(hdc, xc+a, yc+b, NULL); SetPixel(hdc, xc-a, yc+b, NULL); SetPixel(hdc, xc-a, yc-b, NULL); SetPixel(hdc, xc+a, yc-b, NULL); SetPixel(hdc, xc+b, yc+a, NULL); SetPixel(hdc, xc-b, yc+a, NULL); SetPixel(hdc, xc-b, yc-a, NULL); SetPixel(hdc, xc+b, yc-a, NULL); }