Some graphics algorithms

The algorithm draws an ellipse, a circle, and an arc.

 Bresenhanm midpoint algorithm draws an elliptic,

 

Ellipsepanel. Java

 

Package com. Deng. ellipse;

Import java. AWT. color;
Import java. AWT. dimension;
Import java. AWT. graphics;

Import javax. Swing. jpanel;

Public class ellipsepanel extends jpanel {
Private int A, B;
Public ellipsepanel (int A, int B)
{
Super ();
Int temp;
This. A =;
This. B = B;
If (A <B)
{
Temp =;
A = B;
B = temp;
}
Setbackground (color. Black );
Setpreferredsize (New Dimensions (800,600 ));
Repaint ();

}
Public ellipsepanel ()
{
Super ();
This. A = 10;
This. B = 5;
Setbackground (color. Black );
Setpreferredsize (New Dimensions (800,600 ));
Repaint ();
}
// Mom, there is an error when this function name is added with "S!
// There Is A paintcomponents in the container parent class, and I cannot draw any image after heavy loading.
// Then the paintcomponent function does not know where it was reloaded.
// This function name is often written incorrectly.
@ Override
Public void paintcomponent (Graphics g)
{
// Todo auto-generated method stub
Super. paintcomponent (g );
G. setcolor (color. Red );
Midbresenhamellipse (g );
 
 
}
Public void midbresenhamellipse (Graphics g)
{
Int X, Y;
Float D1, D2;
Int basex, basey; // basic coordinates, with the center of the Panel as the coordinate origin
 
X = 0;
Y = B;
D1 = (float) (B * B + A * a * (-B + 0.25 ));
G. setcolor (color. Red );
// Draw coordinates
Basex = (INT) (This. getwidth ()/2 );
Basey = (INT) (This. getheight ()/2 );
G. drawline (0, basey, this. getwidth (), basey );
G. drawline (basex, 0, basex, this. getheight ());
 
// Draw four basic points, which are symmetric points derived from a point.
G. filloval (basex + X, basey + Y, 5, 5 );
G. filloval (basex-X, basey-y, 5, 5 );
G. filloval (basex-X, basey + Y, 5, 5 );
G. filloval (basex + X, basey-y, 5, 5 );
 
While (B * B * (x + 1) <A * a * (y-0.5 ))
{
If (d1 <= 0)
{
D1 = D1 + B * B * (2 * x + 3 );
X ++;
}
Else
{
D1 = D1 + (B * (2 * x + 3) + A * a * (-2 * Y + 2 ));
X ++;
Y --;

}
G. filloval (basex + X, basey + Y, 5, 5 );
G. filloval (basex-X, basey-y, 5, 5 );
G. filloval (basex-X, basey + Y, 5, 5 );
G. filloval (basex + X, basey-y, 5, 5 );
} // While ends part
 
D2 = (float) (B * B * (x + 0.5) * (x + 0.5) + A * a * (Y-1) * (Y-1) -A * a * B * B );

While (Y> 0 ){

If (D2 <= 0)
{
D2 = d2 + B * B * (2 * x + 2) + A * a * (-2 * Y + 3 );
X ++;
Y --;
}
Else
{
D2 = d2 + A * a * (-2 * Y + 3 );
Y --;
}
G. filloval (basex + X, basey + Y, 5, 5 );
G. filloval (basex-X, basey-y, 5, 5 );
G. filloval (basex-X, basey + Y, 5, 5 );
G. filloval (basex + X, basey-y, 5, 5 );
}
 
} // Midbresemham ends

}

 

Bresenhamellipsedriver. Java

 

Package com. Deng. ellipse;

Import javax. Swing. jframe;

Public class bresenhamellipsedriver {
Public static void main (string [] ARGs ){
Jframe frambresenhamellipse = new jframe ("bresenmham ellipse ");
Frambresenhamellipse. setdefaultcloseoperation (jframe. exit_on_close );
Ellipsepanel panelellipse = new ellipsepanel (200,100 );
Frambresenhamellipse. getcontentpane (). Add (panelellipse );
Frambresenhamellipse. Pack ();
Frambresenhamellipse. setvisible (true );
}

}

Bresemham Circle Algorithm

Bresenhamcicledriver. Java

 

Package com. Deng. bresenham;

Import javax. Swing. jframe;

Public class bresenhamcicledriver {
Public static void main (string [] ARGs ){
Jframe framecicleframe = new jframe ("bresenham cicel ");
Framecicleframe. setdefaultcloseoperation (jframe. exit_on_close );
Bresenhamciclepanel Panel = new bresenhamciclepanel (100 );
Framecicleframe. getcontentpane (). Add (panel );
Framecicleframe. Pack ();
Framecicleframe. setvisible (true );
}

}

 

Bresenhamciclepanel. Java

Package com. Deng. bresenham;
// Using bresenham to dra a cicle
Import java. AWT. color;
Import java. AWT. dimension;
Import java. AWT. graphics;

Import javax. Swing. jpanel;

Import com. Deng. cicle. eightpoint;

Public class bresenhamciclepanel extends jpanel {
Private int R;
// Construction
Public bresenhamciclepanel (int r)
{
Super ();
This. r = r; // forget this sentence, so the radius of the circle is 0. How can I say there is no arc?
Setbackground (color. Black );
Setpreferredsize (New Dimensions (800,600 ));
Repaint ();

}
Public bresenhamciclepanel ()
{
This. r = 10;
}
// Draw cicle
@ Override
Public void paintcomponent (Graphics g)
{
// Todo auto-generated method stub
Super. paintcomponent (g );
G. setcolor (color. Red );
Int X, Y, D;
X = 0;
Y = This. R;
D = 1-this.r;
 
While (x <Y ){

Paineightpoint (G, x, y );
// Repaint ();
If (d <0)
D = d + 2 * x + 3;
Else
{
D = d + 2 * (x-y) + 5;
Y --;
}
X ++;

}
}
Public void paineightpoint (Graphics g, int X, int y) // This is the eight-point circle method.
{
Int basex, basey;
G. setcolor (color. Red );
Basex = (INT) (This. getwidth ()/2 );
Basey = (INT) (This. getheight ()/2 );
G. drawline (0, basey, this. getwidth (), basey );
G. drawline (basex, 0, basex, this. getheight ());


// (X, y) x Y series points
G. filloval (basex + X, basey + Y, 5, 5 );
// Eight vertices. In any case, the previous polar coordinates start with basex. Otherwise, the (Yx) series vertices will run incorrectly and are wrong in the past.
// (-X, y)
G. filloval (basex-X, basey + Y, 5, 5 );

// (-X,-y)
G. filloval (basex-X, basey-y, 5, 5 );
// (X,-y)
G. filloval (basex + X, basey-y, 5, 5 );


// (Y, x) Yx Series
G. filloval (basex + Y, basey + X, 5 );

// (-Y, X)
G. filloval (basex-y, basey + X, 5, 5 );


G. filloval (basex-y, basey-X, 5, 5 );
 

G. filloval (basex + Y, basey-X, 5, 5 );


}
 
}

8-Point Circle Algorithm

Eightpoint. Java

Package com. Deng. cicle;

Import java. AWT. color;
Import java. AWT. dimension;
Import java. AWT. graphics;

Import javax. Swing. jpanel;

Public class eightpoint extends jpanel
{
 
Private int X, Y;

// Construction
Public eightpoint (int x, int y)
{
Super ();
This. setbackground (color. Black );
This. setpreferredsize (new dimension (800,600 ));
This. x = X;
This. Y = y;
Repaint ();

} // Construction ends
 
Public void paintcomponent (Graphics g) // The function name is incorrect.
{
Super. paintcomponent (g );
G. setcolor (color. Red );
Eight (G, x, y );

} // Paint graphic function ends

Public void eight (Graphics g, int X, int y)
{

Int basex, basey;
G. setcolor (color. Red );
Basex = (INT) (This. getwidth ()/2 );
Basey = (INT) (This. getheight ()/2 );
G. drawline (0, basey, this. getwidth (), basey );
G. drawline (basex, 0, basex, this. getheight ());


// (X, y) x Y series points
G. filloval (basex + X, basey + Y, 5, 5 );
// Eight vertices. In any case, the preceding polar coordinates start with basex. Otherwise, the (Yx) vertices may run incorrectly.
// (-X, y)
G. filloval (basex-X, basey + Y, 5, 5 );

// (-X,-y)
G. filloval (basex-X, basey-y, 5, 5 );
// (X,-y)
G. filloval (basex + X, basey-y, 5, 5 );


// (Y, x) Yx Series
G. filloval (basex + Y, basey + X, 5 );

// (-Y, X)
G. filloval (basex-y, basey + X, 5, 5 );


G. filloval (basex-y, basey-X, 5, 5 );
 

G. filloval (basex + Y, basey-X, 5, 5 );


}
}

Cicledriver. Java

Package com. Deng. cicle;

Import javax. Swing. jframe;

Public class cicledriver
{
Public static void main (string [] ARGs)
{
Jframe frame = new jframe ("circle and elliptic ");
Frame. setdefaclocloseoperation (jframe. exit_on_close );
Eightpoint eightpanel = new eightpoint (10, 18 );
Frame. getcontentpane (). Add (eightpanel );
Frame. Pack ();
Frame. setvisible (true );
}

}

Draw an arc

Arcpanel. Java

Package com. Deng. Arc;
// Algorithm for generating arcs dynamically, which requires a large amount of Computing
Import java. AWT. color;
Import java. AWT. dimension;
Import java. AWT. graphics;
Import javax. Swing. jpanel;

Public class arcpanel extends jpanel
{
Private int R;
Public arcpanel (int r)
{
Super ();
// Setd (jframe. exit_on_close );
This. r = R;
Setpreferredsize (New Dimensions (800,600 ));
Setbackground (color. Black );
Repaint ();
} // Construction ends

// Reload a method of the parent class, with a 1/8 arc
@ Override
Public void paintcomponent (Graphics g) // the value of "paint" is not "print ".
{
// Todo auto-generated method stub
Super. paintcomponent (g );
G. setcolor (color. Red );
Int X1 = 0;
Int X2;
Int Y2;
Do
{
X2 = X1 + 1;
Y2 = (INT) math. Round (math. SQRT (R * r-x2 * x2 ));
G. fillrect (X2, Y2, 1, 1 );
X1 = x2;

} While (X1 <(R ));
/// (Math. SQRT (2 )));
 
} // Paint ends
 
 
}

Arcdriver. Java

Package com. Deng. Arc;

Import javax. Swing. jframe;

Public class arcdriver {
Public static void main (string [] ARGs ){
Jframe framearc = new jframe ("eight arc ");
Framearc. setdefaclocloseoperation (jframe. exit_on_close );
Arcpanel Panel = new arcpanel (500 );
Framearc. getcontentpane (). Add (panel );
Framearc. Pack ();
Framearc. setvisible (true );
}

}