/****************************************************************************
* Michael Main -- Feb 7, 1992
*
* This is a header file for Xturbo.c which is a
* C module containing routines to simulate the Turbo C++ graphics
* routines in a simple way, using X-windows.
*
* To use the routines:
* 1. In your program put this include statement:
*     #include "~main/Xturbo.h"
* 2. When you compile your program, include these items:
*      g++ ... ~main/Xturbo.o -L/usr/local/X11/lib -lX11
*    The "..." is your program, and "g++" is the c++ compiler.
*
*  These are the routines that are provided:  
*  void initgraphics();  - Call this once before calling anything else.
*  int getmaxx(); - returns maximum x coordinate of the window that's created.
*  int getmaxy(); - returns maximum y coordinate of the window that's created.
*  int maxpage(); - returns the highest page number for different graphics
*    pages, starting at zero.  In this
*    implementation, the highest page number will always be 0 or 1.
*  void setvisualpage(int pagenumber); -- sets visual page to given page
*    number.
*  void setactivepage(int pagenumber); -- sets activepage for drawing.
*  void setcolor(int linecolor); -- sets color for drawing lines, pixels, and
*    the border of polygons.  Colors are currently selected from:
*    0 = black, 1 = white
*  void setfill(int fillcolor); -- sets the color for filling polygons.
*  void line(x1,y1,x2,y2); - draws a line from (x1,y1) to (x2,y2);
*  void plot(x,y); - plots a point at location x,y
*  void fillpoly(int numpoints, short polypoints[]);
*    Polypoints is an array of 2*numpoints shorts, giving the x- and y-pixel
*    coordinates of a polygon which will be drawn.
*  void drawpoly(int numpoints, short polypoints[]); -- draws unfilled polygon.
*  void clearviewport(); - clears the currently active window.
*  void updateall(); - Updates the screen to reflect past calls; i.e., this
*    flushes the output buffer.
*  void closegraph(); - Call this once when you're all done.
****************************************************************************/
      void initgraphics();
      int getmaxx();
      int getmaxy();
      int maxpage();
      void setvisualpage(int pagenumber);
      void setactivepage(int pagenumber);
      void setcolor(int linecolor);
      void setfill(int fillcolor);
      void line(int x1, int y1, int x2, int y2);
      void plot(int x, int y);
      void fillpoly(int numpoints, short polypoints[]);
      void drawpoly(int numpoints, short polypoints[]);
      void clearviewport();
      void closegraph();
      void updateall();