\chapter{Introduction} \pagenumbering{arabic}% \setheader{{\it CHAPTER \thechapter}}{}{}{}{}{{\it CHAPTER \thechapter}}% \setfooter{\thepage}{}{}{}{}{\thepage} Object Graphics Library (\ogl) is a C++ library supporting the creation and manipulation of simple and complex graphic images on a canvas. It can be found in the directory {\tt utils/ogl/src} in the wxWindows distribution. The file {\tt ogl.h} must be included to make use of the library. Please see \helpref{OGL overview}{ogloverview} for a general description how the object library works. For details, please see the \helpref{class reference}{classref}. \section{File structure} These are the files that comprise the \ogl\ library. \begin{description}\itemsep=0pt \item[basic.h] Header for basic objects such as wxShape and wxRectangleShape. \item[basic.cpp] Basic objects implementation (1). \item[basic2.cpp] Basic objects implementation (2). \item[bmpshape.h] wxBitmapShape class header. \item[bmpshape.cpp] wxBitmapShape implementation. \item[canvas.h] wxShapeCanvas class header. \item[canvas.cpp] wxShapeCanvas class implementation. \item[composit.h] Composite object class header. \item[composit.cpp] Composite object class implementation. \item[constrnt.h] Constraint classes header. \item[constrnt.cpp] Constraint classes implementation. \item[divided.h] Divided object class header. \item[divided.cpp] Divided object class implementation. \item[drawn.h] Drawn (metafile) object class header. \item[drawn.cpp] Drawn (metafile) object class implementation. \item[graphics.h] Main include file. \item[lines.h] wxLineShape class header. \item[lines.cpp] wxLineShape class implementation. \item[misc.h] Miscellaneous graphics functions header. \item[misc.cpp] Miscellaneous graphics functions implementation. \item[ogldiag.h] wxDiagram class header. \item[ogldiag.cpp] wxDiagram implementation. \item[mfutils.h] Metafile utilities header. \item[mfutils.cpp] Metafile utilities implementation. \end{description}