The Bifrost Graphics System − TutorialMjølner Informatics ReportMIA 91−19March 2004Copyright © 1991−2004 Mjølner Informatics.All rights reserved.No part of this document may be copied or distributedwithout the prior written permission of Mjølner Informatics The Bifrost Graphics System − TutorialTable of ContentsList of Programs................................................................................................................................1List of Figures....................................................................................................................................21 Introduction.....................................................................................................................................32 The Program Skeleton....................................................................................................................53 Adding the City Map.......................................................................................................................74 Making Stations..............................................................................................................................95 Making Rails..................................................................................................................................126 Moving Stations............................................................................................................................177 Moving ...