function OnGUI()
{	
	if(displayed)
	{	
		GUI.skin = skillInfoStyle;
		
		var posBookX:float = Screen.width/2 -960/2;
		var posBookY:float = Screen.height/2 -960/2;
		var sizePageX:int = 960/2-150;
		var sizePageY:int = 960-310-250; 
		var rectTree:Rect = new Rect(posBookX+960/2+50, posBookY+350, sizePageX, sizePageY);
		var sizeCase:int = 64;
		
		var posCaseX:int[] = new int[5];
		var posCaseY:int[] = new int[5];
		var posCaseYBase:int = 100;	
		posCaseX[0] = sizePageX/6; 	//Offensif 1
		posCaseY[0] = posCaseYBase; 	
		posCaseX[1] = sizePageX/6;	//Offensif 2
		posCaseY[1] = posCaseYBase*2; 
		posCaseX[2] = sizePageX/2; 	//Defensif 1
		posCaseY[2] = posCaseY[0]; 
		posCaseX[3] = sizePageX/2;	//Defensif 2
		posCaseY[3] = posCaseY[1];  
		posCaseX[4] = sizePageX/3;	//Defensif/Offensif
		posCaseY[4] = posCaseYBase*3; 
		
		GUI.BeginGroup(rectTree);  //From here, nothing shows up
		print("ok"); //This message works perfectly fine
		GUI.Box(new Rect(0,0,960,960),""); 
		
		for(i = 0; i < fireSkills.length; i++)
		{
			GUI.DrawTexture(new Rect(posCaseX[i], posCaseY[i]-posCaseYBase/2, sizeCase, sizeCase), caseST);
			GUI.Button(new Rect(posCaseX[i], posCaseY[i]-posCaseYBase/2, sizeCase, sizeCase), "");
		}
		
		GUI.EndGroup(); //From here, everything works fine
		
	}
}