3. /* Rectangular Mesh using set of points f(i,j)=f(xi,yi)
where xi=x0+i*dx, yj=y0+j*dy */
#include<stdlib.h>
#include<GL/glut.h>
#define maxx 20
#define maxy 25
#define dx 15
#define dy 10
// initialize all values of x and y array as 0
GLfloat x[maxx]={0.0},y[maxy]={0.0};
GLfloat x0=50,y0=50; // initial values for x0, y0
GLint i,j;