ellipse drawing program in computer graphics

quadrant is calculated asThe following procedure gives an example of using the midpoint algorithm to display an ellipse. Elliptic Parameters Rx, Ry, Xcenter, and ycenter value of the process Ellipsemidpoint. The position on the first quadrant curve is computed and passed to the procedure ellipseplotpoints. The ellipse position in the other three quadrants is obtained using symmetry, and the

parameter Rx and ryUsing polar coordinates: R and θ, you can also describe a standard position ellipse in the form of a parametric equation:Θ, called an elliptical centrifugal angle (eccentricangle), is measured along the circumference of its enclosing circle. If rx> ry, the radius of the enclosing circle is R = Rx (see figure 3.23), otherwise the radius of the enclosing circle is R = RyAs with the circle algorithm, considering the symmetry of the

Algorithm Description:　　For a general position ellipse, for example, you can pan the center to the coordinate origin, determine the ellipse pixel point set at the standard position of the center at the origin, and then pan to the position, transforming the problem into a standard position of the ellipse's drawing problem.If the long and short axes of an ellipse a

Region 2 isTo simplify the P20. , select the pixel position in the clockwise direction from the recognition (rx,0). The unit step is then taken in the positive y direction until the last position selected in Region 1.By using the equation (3.36) and calculating the pixel position of the entire elliptical trajectory, the midpoint algorithm can be applied to the ellipse that produces the nonstandard position. In addition, the transformation method disc

Seed filling is actually very simple, computer graphics introduced in the use of stacks, feel the author is not brain water, direct use of a queue with a wide search on it, ah, but I do not bother to write, direct a recursive forget, interested students to try their own#include #include #include #include int graph[500][500];void Scanline_seed_fill (int color,int sx,int sy){Graph[sx][sy] = 1;Putpixel (SX, SY

]=1;Putpixel (X0-y,y0-x,color);A[x0-y][y0-x]=1;if (dd+=x*2.0+3;else{d+=2.0* (x-y) +5;y--;}x + +;}}void Edge_mark_fill (int color) {int Driver=vga,mode=vgahi;Initgraph (driver,mode, "");SetBkColor (0);int x;int y;Midpointcircle (100,100,100,255);Midpointcircle (301,100,100,255);//Circle stagger a bitDraw graphicsFor (x=0,y=100;x{Putpixel (X,y,color);A[x][y]=1;}200 Stagger a bitFor (x=201,y=300;x{Putpixel (X,y,color);A[x][y]=1;}BOOL Inside=false;for (y=0;y{Inside=false;for (x=0;x{if (side[y]==1)Br