gistfile1.cs

Vector3 mousePosition = MouseUtils.ConvertMousePositionToWorldPosition(Input.mousePosition,
                                                                       ScenarioData.MinPointToView,			                                                                                                                   
                                                                       ScenarioData.MaxPointToView);

public class MouseUtils {

	public static Vector3 ConvertMousePositionToWorldPosition(Vector3 mousePosition,
	                                                          Vector3 minPoint,
	                                                          Vector3 maxPoint)
	{
		mousePosition.x = ((mousePosition.x / (float)Screen.width)  * (maxPoint.x - minPoint.x)) + minPoint.x;
		mousePosition.y = ((mousePosition.y / (float)Screen.height) * (maxPoint.y - minPoint.y)) + minPoint.y;
		return mousePosition;
	}
}

public class ScenarioData
{
	public static Vector3 MaxPointToView = new Vector3( 14f, 14f,  0.1f);
	public static Vector3 MinPointToView = new Vector3(-14f, -1f, -0.1f);
}