#include <windows.h>
#include <GL/glut.h>
#include <stdio.h>
#include <string.h>
int *pv, *pn; // variabile globale, pointeri la n si v[]

void display() {
	   char numar[3];
	   int i, j;
	   float dx, ky, max;
	   dx = 1.9 / *pn; // spatiul pe x pt un dreptunghi - dx
	   // determinarea valorii maxime din vector
	   max = *pv;
	   for(i = 1; i < *pn; i++)
		   if(max < *(pv + i))
			   max = *(pv + i);
	   ky = 1.8 / max; // factorul de scalare pe y, lui max ii corespunde 1.8
	   glClearColor(1.0f, 1.0f, 1.0f, 0.05f);
	   glClear(GL_COLOR_BUFFER_BIT);
	   for(i = 0; i < *pn; i++){
		   glBegin(GL_QUADS);
		   glColor3f(0.0f, 0, 1.0f);
		   glVertex2f(-0.95 + i * dx, -0.9);
		   glVertex2f(-0.95 + (i + 1) * dx - 0.02, -0.9);
		   glVertex2f(-0.95 + (i + 1) * dx - 0.02, -0.9 + *(pv+i) * ky );
		   glVertex2f(-0.95 + i * dx, -0.9 + *(pv+i) * ky );
		   glEnd();
		   // afisare etichete text
		   sprintf(numar,"%d",*(pv+i));
	      glRasterPos2f(-0.95 + i * dx + dx / 2, -0.9 + *(pv+i) * ky + 0.05);
	     for(j = 0; j < strlen(numar); j++)
		       glutBitmapCharacter(GLUT_BITMAP_TIMES_ROMAN_10,numar[j]);
	  }
	   glFlush();
}
int main(int argc, char** argv){
   int i, n, v[20];
   pv = v;
   pn = &n;
   printf("Nr. de elemente:");
   fflush(stdout);
   scanf("%d", &n);
   for(i = 0; i < n; i++){
	   printf("v[%d] = ", i);
	   fflush(stdout);
	   scanf("%d", &v[i]);
   }

   glutInit(&argc, argv);
   glutCreateWindow("Testare mod grafic OpenGL ");
   glutInitWindowSize(320, 320);
   glutInitWindowPosition(50, 50);
   glutDisplayFunc(display);
   glutMainLoop();
   return 0;
}