points.cpp

使用Breshren算法做的

#include<windows.h>
#include<gl/glut.h>
 void myinit(void)
 {
   glClearColor(1.0,1.0,1.0,1.0);/*设置背景色*/
 }

 void DrawOnePoint(int x1,int y1)
 {
 glBegin(GL_POINTS);
   glVertex2f(x1,y1);
   glEnd();
 
 }

 
void Bresenham_Line (void)
{
    int x0=10,y0=10,x1=70,y1=30;
	int dx,dy,e,i,x,y;
    dx = x1-x0, dy = y1- y0, e=2*dy-dx; 	
    x=x0, y=y0;	
	 glClear(GL_COLOR_BUFFER_BIT);
	 /*设置的颜色*/
	 glColor3f(1.0,0.0,0.0);
    for (i=0; i<=dx; i++)		
    {
		glPointSize(2);
                    DrawOnePoint (x, y); 			
                         x++; 
                     e=e+2*dy; 
                     if (e>=0)
                      { 
                       y++; 
                       e=e-2*dx;
                      }		
      }
	glFlush(); 
 }	


 void myreshape(int w ,int h)
 {
   glViewport(0,0,(GLsizei)w,(GLsizei)h);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   gluOrtho2D(0.0,(GLdouble)w,0.0,(GLdouble)h);
 }

 int main (int argc,char**argv)
 {
   glutInit(&argc,argv);
   glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB);
   glutInitWindowSize(200,200);
   glutInitWindowPosition(150,150);
   glutCreateWindow("Points");
   myinit();
   glutDisplayFunc(Bresenham_Line);
   glutReshapeFunc(myreshape);
   glutMainLoop();
   return 0;
 
 }