Breaseman Algorithm Draw Circle | Midpoint Algorithm Draw Circle _ program Fragment

Breaseman Algorithm Draw Circle | Midpoint Algorithm Draw Circle _ program Fragment

1. Breaseman algorithm to draw round program

Due to the particularity of the algorithm, the first quadrant is limited, and the other parts are drawn by rotation.

1 voidCcgprojectworkview::bresenham_1p4circle (intRadiumConst floatlinecolor[])2 {3     intPointx, Pointy, Deltd, DELTHD, DELTDV, direction;4Pointx =0;5Pointy =Radium;6Deltd =2*(1-radium);7 8glcolor3f (linecolor[0], linecolor[1], linecolor[2]);9 Glbegin (gl_points);Ten      while(Pointy >=0) One     { Aglvertex3f (Pointx, pointy,0); -         if(Deltd <0)//D point in the circle -         { theDELTHD =2* (Deltd+pointy)-1; -             if(Delthd <=0) -Direction =1;//H Point Distance nearest -             Else +Direction =2;//D Point Distance nearest -         } +         Else if(Deltd >0)//d points outside the circle A         { atDELTDV =2* (DELTD-POINTX)-1; -             if(Deltdv <=0)//It 's the worst in point D . -Direction =2; -             Else -Direction =3;//V-point distance nearest -         } in         Else -Direction =2;//D on the Circle to         Switch(direction) +         { -          Case 1: the             //H Point Position *pointx++; $Deltd + =2*pointx+1;Panax Notoginseng              Break; -          Case 2: the             //D-Point location +pointx++; Apointy--; theDeltd + =2* (pointx-pointy+1); +              Break; -          Case 3: $             //V-point position $pointy--; -Deltd + = (-2*pointy+1); -              Break; the         default : -              Break;Wuyi         } the     } - glend (); Wu  -}

2. Midpoint algorithm Draws a circle

Due to the particularity of the algorithm, the program restricts 1/8 parts of the first quadrant.

1 //1/8 Park on the left side of the first quadrant.2 voidCcgprojectworkview::midpoint_1p8circle (intRadiumConst floatlinecolor[])3 {4     intPointx, pointy, R;5     floatDistjugefactor;6R =Radium;7     intDeltx, delty;//recursive components of the components of X and Y in the judging factor8Deltx =3;9Delty =2-R-R;TenDistjugefactor =1-R; One  APointx =0; -Pointy =Radium; -glcolor3f (linecolor[0], linecolor[1], linecolor[2]); the Glbegin (gl_points); -glvertex3f (Pointx, pointy,0); -          while(Pointx <pointy) -         { +             if(Distjugefactor <0)//Midpoint in Circle -             { +Distjugefactor + =Deltx; ADeltx + =2; atpointx++; -             } -             Else -             { -Distjugefactor + = Deltx +delty; -Deltx + =2; inDelty + =2; -pointx++; topointy--; +             } -glvertex3f (Pointx, pointy,0); the         } * glend (); $ Panax Notoginseng}

Breaseman Algorithm Draw Circle | Midpoint Algorithm Draw Circle _ program Fragment