Merge pull request #129 from kumarvivek8/patch-10

Create program4.cpp

Author: sunnyshahabuddin

program4.cpp

@@ -0,0 +1,77 @@
+#include<GL/glut.h>
+#include<stdlib.h>
+#include<iostream>
+#include<math.h>
+using namespace std;
+int pntX1, pntY1, r;
+void plot(int x, int y)
+{
+glBegin(GL_POINTS);
+glVertex2i(x + pntX1, y + pntY1);
+glEnd();
+}
+void myInit(void)
+{
+glClearColor(0.2, 0.3, 0.4, 0.5);
+glColor3f(0.5f, 0.6f, 0.7f);
+glPointSize(4.0);
+glMatrixMode(GL_PROJECTION);
+glLoadIdentity();
+gluOrtho2D(0.0, 640.0, 0.0, 480.0);
+}
+void midPointCircleAlgo()
+{
+int x = 0;
+int y = r;
+float decision=5/4-r;
+plot(x,y);
+while (y>x)
+{
+if (decision<0)
+{
+x++;
+decision += 2 * x + 1;
+}
+else
+{
+y--;
+x++;
+decision+=2*(x-y)+1;
+
+}
+plot(x,y);
+plot(x,-y);
+plot(-x,y);
+plot(-x,-y);
+plot(y,x);
+plot(-y,x);
+plot(y,-x);
+plot(-y,-x);
+}
+}
+void myDisplay(void)
+{
+glClear(GL_COLOR_BUFFER_BIT);
+glColor3f(0.5, 0.2, 0.7);
+glPointSize(1.0);
+midPointCircleAlgo();
+glFlush();
+}
+int main(int argc, char** argv)
+{
+cout << "Enter the center's coordinates:"<<endl;
+cout << "X-coordinate:"; 
+cin>>pntX1;
+cout << "\nY-coordinate:";
+cin>>pntY1;
+cout << "\nEnter radius:"; 
+cin>>r;
+glutInit(&argc, argv);
+glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
+glutInitWindowSize(640, 480);
+glutInitWindowPosition(100, 150);
+glutCreateWindow("Circle Mid Point Alogrithm");
+glutDisplayFunc(myDisplay);
+myInit();
+glutMainLoop();
+}