tomwalters@0: /*
tomwalters@0: 	Still to consider:
tomwalters@0: 
tomwalters@0:     A structure for a box-object, containing a complete set of internal
tomwalters@0:     variables for one box. A routine could allocate a structure, call the
tomwalters@0:     routines set_box_parameters() and set_data_parameters(), and return a ptr
tomwalters@0:     to the structure. Now a set of #defines could take a structure pointer
tomwalters@0:     (just as they currently often take a window ptr), and could call the
tomwalters@0:     appropriate sub-routines using the internal variables for that box.
tomwalters@0:     (The window could be a member of the structute too).
tomwalters@0: 
tomwalters@0:     With this, you could easily maintain a set of boxes, and plot anything
tomwalters@0:     in any of them. But if you need ore than one window, then you'll need a
tomwalters@0:     window structure too, (to hold window parameters for each window).
tomwalters@0:     For example:
tomwalters@0: 
tomwalters@0:     struct st_window {
tomwalters@0: 	Window          w;
tomwalters@0: 	int             x,y;            window origin wrt display
tomwalters@0: 	unsigned int    width,height;   window size
tomwalters@0: 	GC              gc;
tomwalters@0:     };
tomwalters@0: 
tomwalters@0:     struct st_box {
tomwalters@0: 	struct st_window * pt;          parent window
tomwalters@0: 	char *fname;                    file name for data
tomwalters@0: 	int   n, s;                     num points and start point in file
tomwalters@0: 	...all system variables...
tomwalters@0:     };
tomwalters@0: 
tomwalters@0: */
tomwalters@0: 
tomwalters@0: 
tomwalters@0: /****************************************************************************
tomwalters@0: 
tomwalters@0:     x11coord.h    A file for inclusion into X11 plotting programs.
tomwalters@0:     ----------    (See x11test.c for example).
tomwalters@0: 
tomwalters@0:  ****************************************************************************
tomwalters@0: 
tomwalters@0: User parameters:
tomwalters@0: ================
tomwalters@0: 1. Window parameters - Set size and position of a window on the display.
tomwalters@0:     set_window_parameters(xorg,yorg, width,height)
tomwalters@0:     int   xorg,yorg       Window origin (pixel coords of top-left wrt Display).
tomwalters@0:     int   width,height    Window size (pixels).
tomwalters@0: 
tomwalters@0: 2. Box parameters -    Set size and position of a box in a preset window.
tomwalters@0:  a) set_box_parameters(xorg,yorg, width,height)
tomwalters@0:     int   xorg,yorg       Box origin (pixel coords of bottom-left wrt window).
tomwalters@0:     int   width,height    Box size (pixels).
tomwalters@0:  b) set_bordered_box(bpc)
tomwalters@0:     int   bpc             Box border (constant width) as %age of window size.
tomwalters@0: 
tomwalters@0: 3. Data parameters -   Set area and location of data space to appear in box.
tomwalters@0:     set_data_parameters(xp0,yp0, xd0,yd0, xrange,yrange)
tomwalters@0:     int   xp0,yp0         Plot origin (as a %age of box size from box origin).
tomwalters@0:     float xd0,yd0         Data origin (data coords to appear under plot origin).
tomwalters@0:     float xrange,yrange   Data ranges (area of data space to appear under plot).
tomwalters@0: 
tomwalters@0: Notes:
tomwalters@0: 1. Pixel coordinates and sizes are ints. Data coordinates and sizes are floats.
tomwalters@0: 2. Pixel coords refer to the X11 coord system which has origin (0,0) in the
tomwalters@0:    top-left of each window. Data coords refer to the user coord system which
tomwalters@0:    has its origin (0,0) in the bottom-left of each box.
tomwalters@0: 3. The parameter initialization routines must be called in order, (window,
tomwalters@0:    box, data), and must be done first, otherwise macros which use the system
tomwalters@0:    variables will not work. As a minimum, you MUST do set_window_parameters(),
tomwalters@0:    and this will give you a box the same size as the window, with origin in
tomwalters@0:    the bottom-left, with data origin at the box origin, and data ranges the
tomwalters@0:    same as pixels.
tomwalters@0: 4. Although its true that set_window_parameters only sets window pixel sizes,
tomwalters@0:    set_box_parameters only sets box pixel sizes, and set_data_parameters only
tomwalters@0:    sets data sizes, the data sizes are somewhat dependent upon the pixel
tomwalters@0:    sizes, and so if you change the window or box parameters during a program,
tomwalters@0:    (eg, to resize a box), then you must re-initialize set_data_parameters at
tomwalters@0:    the same time. (Call it again with the same initial arguments; it will
tomwalters@0:    re-initialize internal parameters).
tomwalters@0: 
tomwalters@0: User routines and macros:
tomwalters@0: =========================
tomwalters@0: Set system private parameters.
tomwalters@0: -----------------------------
tomwalters@0: 	      set_window_parameters(xorg,yorg, width,height)
tomwalters@0: 	      set_box_parameters(xorg,yorg, width,height)
tomwalters@0: 	      set_bordered_box(bpc)
tomwalters@0: 	      set_data_parameters(xp0,yp0, xd0,yd0, xrange,yrange)
tomwalters@0: Open connection and create window.
tomwalters@0: ---------------------------------
tomwalters@0: 	      xopen()
tomwalters@0: Window        xcreate(name, event_mask)
tomwalters@0: Convert coordinates.
tomwalters@0: -------------------
tomwalters@0: int           px(x)
tomwalters@0: int           py(y)
tomwalters@0: float         xp(p)
tomwalters@0: float         yp(p)
tomwalters@0: float         xpc(pc)
tomwalters@0: float         ypc(pc)
tomwalters@0: Return pixel coordinates.
tomwalters@0: -----------------------
tomwalters@0: int           pleft()
tomwalters@0: int           pright()
tomwalters@0: int           pbottom()
tomwalters@0: int           ptop()
tomwalters@0: int           pwidth()
tomwalters@0: int           pheight()
tomwalters@0: Return data coordinates.
tomwalters@0: -----------------------
tomwalters@0: float         xleft()
tomwalters@0: float         xright()
tomwalters@0: float         ybottom()
tomwalters@0: float         ytop()
tomwalters@0: float         xwidth()
tomwalters@0: float         yheight()
tomwalters@0: float         xcentre()
tomwalters@0: float         ycentre()
tomwalters@0: float         Xjitter(x,p)
tomwalters@0: float         Yjitter(y,p)
tomwalters@0: Test data coordinates.
tomwalters@0: ---------------------
tomwalters@0: bool          Xinbox(x)
tomwalters@0: bool          Yinbox(y)
tomwalters@0: bool          inbox(x,y)
tomwalters@0: Draw and calibrate boxes and axes.
tomwalters@0: ---------------------------------
tomwalters@0: 	      draw_Xaxis(w,yval)
tomwalters@0: 	      calibrate_Xaxis(w,yval)
tomwalters@0: 	      draw_Yaxis(w,xval)
tomwalters@0: 	      calibrate_Yaxis(w,xval)
tomwalters@0: 	      draw_box(w)
tomwalters@0: 	      calibrate_box(w)
tomwalters@0: 	      draw_calibrated_box(w)
tomwalters@0: Draw points, lines, and strings, etc..
tomwalters@0: -------------------------------------
tomwalters@0: 	      setLinewidth(width)
tomwalters@0: 	      Point(w,x,y)
tomwalters@0: 	      xPoint(w,x,y)
tomwalters@0: 	      Line(w,x1,y1,x2,y2)
tomwalters@0: 	      xLine(w,x1,y1,x2,y2)
tomwalters@0: 	      String(w,x,y,string)
tomwalters@0: 	      xString(w,x,y,string)
tomwalters@0: 	      Cross(w,x,y)
tomwalters@0: 	      xCross(w,x,y)
tomwalters@0: 	      Dot(w,x,y,dotsize)
tomwalters@0: 	      xDot(w,x,y,dotsize)
tomwalters@0: Text string parameters.
tomwalters@0: -----------------------
tomwalters@0: 	      setFont("fontname")
tomwalters@0: int           nlines()
tomwalters@0: int           ncols()
tomwalters@0: Return pixel sizes based on current "theFont".
tomwalters@0: ----------------------------------------------
tomwalters@0: int           max_charwidth()
tomwalters@0: int           max_charheight()
tomwalters@0: int           stringwidth(string)
tomwalters@0: int           stringheight(string)
tomwalters@0: int           linespacing()             white space between lines.
tomwalters@0: int           lineheight()              total line (y-value) increment.
tomwalters@0: int           colwidth()                total character (x-value) increment.
tomwalters@0: int           margin()                  white space at sides of page.
tomwalters@0: int           headroom()                white space at head and foot of page.
tomwalters@0: Return pixel coordinates.
tomwalters@0: -------------------------
tomwalters@0: int           leftmargin()
tomwalters@0: int           rightmargin()
tomwalters@0: int           topmargin()
tomwalters@0: int           bottommargin()
tomwalters@0: int           line(i)
tomwalters@0: int           col(j)
tomwalters@0: Draw text strings.
tomwalters@0: ------------------
tomwalters@0: 	      topline(w,string)
tomwalters@0: 	      bottomline(w,string)
tomwalters@0: 	      lineString(w,string,i,j)
tomwalters@0: 	      leftString(w,string,i)
tomwalters@0: 	      rightString(w,string,i)
tomwalters@0: 	      centreString(w,string,i)
tomwalters@0: 	      supertopline(w,string)
tomwalters@0: 
tomwalters@0: 
tomwalters@0: Notes:
tomwalters@0: 1. The user routines conventionally take data coordinate arguments.
tomwalters@0:    To convert pixel coordinates to data, use the xp,yp macros.
tomwalters@0: 
tomwalters@0: Development of coord system scaling transformations:
tomwalters@0: ====================================================
tomwalters@0: Internal variables (initialized by the `set' routines and used by the `px'
tomwalters@0: macros) are pixel coords and sizes, and refer to the X11 coord system:
tomwalters@0: 
tomwalters@0: 		|    _Xp0       |
tomwalters@0: 		+---------------+
tomwalters@0: 		|               |
tomwalters@0: 
tomwalters@0: 		|          _Xp1             |
tomwalters@0: 		+---------------------------+
tomwalters@0: 		|                           |
tomwalters@0: 	    (0,0)
tomwalters@0:    -+-    -+-   +-------------------------------------------+
tomwalters@0:     |      |    |Window                                     |
tomwalters@0:     |  _Yp1|    |                                           |
tomwalters@0:     |      |    |                    _Wb                    |
tomwalters@0: _Yp0|     -+-   |   (_Xp0,_Yp1) +-----------+ (_Xp1,_Yp1)   |
tomwalters@0:     |           |               |Box        |               |
tomwalters@0:     |           |               |           |_Hb            |
tomwalters@0:     |           |               |           |               |
tomwalters@0:    -+-          |   (_Xp0,_Yp0) +-----------+ (_Xp1,_Yp0)   |
tomwalters@0: 		|                                           |
tomwalters@0: 		|                                           |
tomwalters@0: 		|                                           |
tomwalters@0: 		+-------------------------------------------+
tomwalters@0: 
tomwalters@0: Consider a box of width Wb pixels (on horizontal axis) and height Hb pixels
tomwalters@0: (on vertical axis). Let this box size represent data ranges xrange and yrange,
tomwalters@0: (corresponding to Wb and Hb respectively). Let the pixel origin and the data
tomwalters@0: origin be superimposed at (0,0) in the bottom-left corner. Then a data coord
tomwalters@0: (x,y) is transformed into a pixel coord by the scaling:
tomwalters@0:     px(x) = x * Wb/xrange
tomwalters@0:     py(y) = y * Hb/yrange
tomwalters@0: 
tomwalters@0: If the data coordinate which we wish to appear at the plot origin is actually
tomwalters@0: (xd0,yd0), then the data origin must be shifted off the pixel origin, so that
tomwalters@0: the data coord (xd0,yd0) is represented by pixel coord (0,0). Hence:
tomwalters@0:     px(x) = (x-xd0) * Wb/xrange
tomwalters@0:     py(y) = (y-yd0) * Hb/yrange
tomwalters@0: 
tomwalters@0: It is necessary to invert the y-axis so that pixel coords are consistent with
tomwalters@0: the X11 coord system, (with pixel origin in the top-left of a window and pixel
tomwalters@0: y-values which increase down the window). Let the box be positioned in the
tomwalters@0: top-left corner of its parent window, so that the X11 origin corresponds with
tomwalters@0: the top-left corner of the box. Then the y-axis is inverted by:
tomwalters@0:     px(x) =      (x-xd0) * Wb/xrange
tomwalters@0:     py(y) = Hb - (y-yd0) * Hb/yrange
tomwalters@0: 
tomwalters@0: In general, the box will be positioned within its parent window as in the
tomwalters@0: diagram above. The box is shifted into the window by an x-value Xp0 and a
tomwalters@0: y-value Yp1, and these must be added to any pixel coordinate:
tomwalters@0:     px(x) = Xp0      + (x-xd0) * Wb/xrange
tomwalters@0:     py(y) = Yp1 + Hb - (y-yd0) * Hb/yrange
tomwalters@0: 
tomwalters@0: Although Yp0 is the y-value at the bottom of the box, at its default origin,
tomwalters@0: note that Yp0>Yp1, since y-values increase down the window in the X11 pixel
tomwalters@0: coordinate system.
tomwalters@0: Finally, we may want the user origin of the box to be somewhere other than the
tomwalters@0: bottom-left corner, (Eg, scatter plots often have the user origin in the
tomwalters@0: centre of the plot; time-waveform plot often have the origin half-way up the
tomwalters@0: left side of the plot). To place the user origin at a pixel coordinate of
tomwalters@0: (xshift,yshift), we add xshift and subtract yshift from the transformed pixel
tomwalters@0: coordinates. (We subtract yshift since the transformed pixel coord is in the
tomwalters@0: X11 coord system). So we have:
tomwalters@0:     px(x) = Xp0      + xshift + (x-xd0) * Wb/xrange
tomwalters@0:     py(y) = Yp1 + Hb - yshift - (y-yd0) * Hb/yrange
tomwalters@0: 
tomwalters@0: Grouping terms we have:
tomwalters@0:     px(x) = Xp0      + xshift - xd0*Wb/xrange + x*Wb/xrange
tomwalters@0:     py(y) = Yp1 + Hb - yshift + yd0*Hb/yrange - y*Hb/yrange
tomwalters@0: 
tomwalters@0: Now substituting:
tomwalters@0:       xoffset = Xp0      + xshift - xd0*Wb/xrange ;     xscale = Wb/xrange
tomwalters@0:       yoffset = Yp1 + Hb - yshift + yd0*Hb/yrange ;     yscale = Hb/yrange
tomwalters@0: We have:
tomwalters@0:     px(x) = xoffset + x * xscale
tomwalters@0:     py(y) = yoffset - y * yscale
tomwalters@0: 
tomwalters@0: The inverse transformations xp(p) and yp(p) are just the inverse of these.
tomwalters@0: 
tomwalters@0: A typical program might be as follows:
tomwalters@0: -------------------------------------
tomwalters@0: 	------------------------------------------------------------------
tomwalters@0:        |#include <stdio.h>                                                |
tomwalters@0:        |#include <math.h>                                                 |
tomwalters@0:        |                                                                  |
tomwalters@0:        |#include "x11coord.h"                                             |
tomwalters@0:        |                                                                  |
tomwalters@0:        |                                                                  |
tomwalters@0:        |main()                                                            |
tomwalters@0:        |{                                                                 |
tomwalters@0:        |    Window w;                                                     |
tomwalters@0:        |        .....                                                     |
tomwalters@0:        |                                                                  |
tomwalters@0:        |    set_window_parameters(100,85, 775,775);                       |
tomwalters@0:        |    set_bordered_box(10);                                         |
tomwalters@0:        |    set_data_parameters(50,50, 0,0, 2.0,2.0);                     |
tomwalters@0:        |                                                                  |
tomwalters@0:        |    xopen();                                                      |
tomwalters@0:        |    w = xcreate("test", ButtonPressMask | ExposureMask);          |
tomwalters@0:        |    xevent_monitor(w);                                            |
tomwalters@0:        |}                                                                 |
tomwalters@0:        |                                                                  |
tomwalters@0:        |                                                                  |
tomwalters@0:        |xevent_monitor(w)                                                 |
tomwalters@0:        |Window w;                                                         |
tomwalters@0:        |{                                                                 |
tomwalters@0:        |    XEvent event;                                                 |
tomwalters@0:        |                                                                  |
tomwalters@0:        |    for ( ; ; ) {                                                 |
tomwalters@0:        |        XNextEvent(theDisplay,&event);                            |
tomwalters@0:        |        switch (event.type) {                                     |
tomwalters@0:        |            ....                                                  |
tomwalters@0:        |            case ButtonPress:                                     |
tomwalters@0:        |                switch(event.xbutton.button) {                    |
tomwalters@0:        |                    case Button1:                                 |
tomwalters@0:        |                        XDestroyWindow(theDisplay,w);             |
tomwalters@0:        |                        return;                                   |
tomwalters@0:        |                    case Button2:                                 |
tomwalters@0:        |                        ....                                      |
tomwalters@0:        |                }                                                 |
tomwalters@0:        |                break;                                            |
tomwalters@0:        |            case Expose:                                          |
tomwalters@0:        |                if (event.xexpose.count == 0) {                   |
tomwalters@0:        |                    draw_calibrated_box(w);                       |
tomwalters@0:        |                    plot(w);                                      |
tomwalters@0:        |                }                                                 |
tomwalters@0:        |                break;                                            |
tomwalters@0:        |            ....                                                  |
tomwalters@0:        |        }                                                         |
tomwalters@0:        |    }                                                             |
tomwalters@0:        |}                                                                 |
tomwalters@0:        |                                                                  |
tomwalters@0: 	------------------------------------------------------------------
tomwalters@0: The purpose of the xevent_monitor is to loop endlessly and keep the program
tomwalters@0: running while the window is displayed. The window vanishes when the monitor
tomwalters@0: is quit using (in this example) the left mouse button.
tomwalters@0: Note that you let all plotting routines be called when an expose-event has
tomwalters@0: been caught. This is not just so that the screen re-draws itself when exposed,
tomwalters@0: but also to avoid data at the start of the plot going missing.
tomwalters@0: If you don't set up for expose-events, but try to plot data as soon as the
tomwalters@0: window is created, then it turns out that you tend to lose the first few bytes
tomwalters@0: of plot data. The correct way is to plot data when the window is exposed.
tomwalters@0: The window-creation and mapping process generates an expose event
tomwalters@0: automatically and, when caught by the event monitor, this causes the window to
tomwalters@0: be first plotted.
tomwalters@0: 
tomwalters@0: 
tomwalters@0: *****************************************************************************/
tomwalters@0: #include <X11/X.h>      /*  /usr/include/X11/X.h     */
tomwalters@0: #include <X11/Xlib.h>   /*  /usr/include/X11/Xlib.h  */
tomwalters@0: 
tomwalters@0: 
tomwalters@0: static char defFontString[] = "fixed" ,  *theFontString = defFontString ;
tomwalters@0: 
tomwalters@0: 
tomwalters@0: /****************************************************************************
tomwalters@0: *       Defaults for some standard window sizes
tomwalters@0: ****************************************************************************/
tomwalters@0: #define FULLXORG          5     /* Full screen size */
tomwalters@0: #define FULLYORG         90
tomwalters@0: #define FULLWIDTH      1000
tomwalters@0: #define FULLHEIGHT      750
tomwalters@0: 
tomwalters@0: #define A4XORG          190     /* A4 size */
tomwalters@0: #define A4YORG           85
tomwalters@0: #define A4WIDTH         620
tomwalters@0: #define A4HEIGHT        760
tomwalters@0: 
tomwalters@0: #define PLOTXORG        100     /* Rectangular plotting area */
tomwalters@0: #define PLOTYORG        155
tomwalters@0: #define PLOTWIDTH       800
tomwalters@0: #define PLOTHEIGHT      600
tomwalters@0: 
tomwalters@0: #define BOXXORG         100     /* Square box */
tomwalters@0: #define BOXYORG          85
tomwalters@0: #define BOXWIDTH        775
tomwalters@0: #define BOXHEIGHT       775
tomwalters@0: 
tomwalters@0: /****************************************************************************
tomwalters@0: *       Macros for pixel-data transformation
tomwalters@0: ****************************************************************************/
tomwalters@0: /* pixel coord from data coord */
tomwalters@0: #define px(x)           ( (int)(_xoffset + (x) * _xscale) )
tomwalters@0: #define py(y)           ( (int)(_yoffset - (y) * _yscale) )
tomwalters@0: /* data coord from pixel coord */
tomwalters@0: #define xp(p)           ( (float)(((p) - _xoffset) / _xscale) )
tomwalters@0: #define yp(p)           ( (float)((_yoffset - (p)) / _yscale) )
tomwalters@0: /* data coord from a %age of data range */
tomwalters@0: #define xpc(pc)         ( ((xleft()+xright())*pc) / 100 )
tomwalters@0: #define ypc(pc)         ( ((ybottom()+ytop())*pc) / 100 )
tomwalters@0: /* data coord of box centre */
tomwalters@0: #define xcentre()       xpc(50)
tomwalters@0: #define ycentre()       ypc(50)
tomwalters@0: /* pixel limits of box (note that ptop() < pbottom() ). */
tomwalters@0: #define pleft()         (_Xp0)
tomwalters@0: #define pright()        (_Xp1)
tomwalters@0: #define pbottom()       (_Yp0)
tomwalters@0: #define ptop()          (_Yp1)
tomwalters@0: #define pwidth()        (_Wb)
tomwalters@0: #define pheight()       (_Hb)
tomwalters@0: /* data limits of box */
tomwalters@0: #define xleft()         xp(_Xp0)
tomwalters@0: #define xright()        xp(_Xp1)
tomwalters@0: #define ybottom()       yp(_Yp0)
tomwalters@0: #define ytop()          yp(_Yp1)
tomwalters@0: #define xwidth()        xp(_Wb)
tomwalters@0: #define yheight()       yp(_Hb)
tomwalters@0: /* test if data argument is in box */
tomwalters@0: #define Xinbox(x)       ( (xleft()<=x && x<=xright()) ? 1 : 0 )
tomwalters@0: #define Yinbox(y)       ( (ybottom()<=y && y<=ytop()) ? 1 : 0 )
tomwalters@0: #define inbox(x,y)      ( (Xinbox(x) && Yinbox(y)) ? 1 : 0 )
tomwalters@0: /* jitter data value (ie move by a given pixel distance) */
tomwalters@0: #define Xjitter(x,p)    ( xp(px(x)+(p)) )
tomwalters@0: #define Yjitter(y,p)    ( yp(py(y)+(p)) )
tomwalters@0: 
tomwalters@0: /****************************************************************************
tomwalters@0: *       Macros for routines (using preset system parameters)
tomwalters@0: ****************************************************************************/
tomwalters@0: /* Xaxes: yval is a data value at which to place a horizontal axis.        */
tomwalters@0: /* For example: 0 (zero line), ybottom() (box-bottom), ytop() (box-top).   */
tomwalters@0: #define draw_Xaxis(w,yval)      if (Yinbox(yval)) axis(w, _Xp0,_Xp1, py(yval),'x')
tomwalters@0: #define calibrate_Xaxis(w,yval) calibrate_Axis(w, _Xp0,_Xp1, _Xd0,_Xd1, py(yval),'x')
tomwalters@0: 
tomwalters@0: /* Yaxes: xval is a data value at which to place a vertical axis.          */
tomwalters@0: /* For example: 0 (zero line), xleft() (box-left), xright() (box-right).   */
tomwalters@0: #define draw_Yaxis(w,xval)      if (Xinbox(xval)) axis(w, _Yp0,_Yp1, px(xval),'y')
tomwalters@0: #define calibrate_Yaxis(w,xval) calibrate_Axis(w, _Yp0,_Yp1, _Yd0,_Yd1, px(xval),'y')
tomwalters@0: 
tomwalters@0: #define draw_box(w)             box(w, _Xp0,_Yp0, _Xp1,_Yp1)
tomwalters@0: #define calibrate_box(w)        calibrate_Box(w, _Xp0,_Yp0, _Xp1,_Yp1, _Xd0,_Yd0, _Xd1,_Yd1)
tomwalters@0: #define draw_calibrated_box(w)  draw_box(w); calibrate_box(w)
tomwalters@0: 
tomwalters@0: #define xcreate(name,mask)      xCreate(name,mask, _xorg,_yorg, _width,_height)
tomwalters@0: 
tomwalters@0: /****************************************************************************
tomwalters@0: *       Macros for standard X11 commands
tomwalters@0: ****************************************************************************/
tomwalters@0: #define Point(w,x,y)            XDrawPoint(theDisplay,w,theGC,px(x),py(y))
tomwalters@0: #define Line(w,x1,y1,x2,y2)     XDrawLine(theDisplay,w,theGC,px(x1),py(y1),px(x2),py(y2))
tomwalters@0: #define String(w,x,y,string)    XDrawString(theDisplay, w, theGC, px(x),py(y), string, strlen(string))
tomwalters@0: 
tomwalters@0: #define Cross(w,x,y)            XDrawLine(theDisplay,w,theGC,px(x)-10,py(y),px(x)+10,py(y)); XDrawLine(theDisplay,w,theGC,px(x),py(y)-10,px(x),py(y)+10)
tomwalters@0: 
tomwalters@0: #define xPoint(w,x,y)           if (inbox(x,y)) Point(w,x,y)
tomwalters@0: #define xLine(w,x1,y1,x2,y2)    if (inbox(x1,y1) && inbox(x2,y2)) Line(w,x1,y1,x2,y2)
tomwalters@0: #define xString(w,x,y,string)   if (inbox(x,y)) String(w,x,y,string)
tomwalters@0: 
tomwalters@0: #define xCross(w,x,y)           if (inbox(x,y)) Cross(w,x,y)
tomwalters@0: #define xDot(w,x,y,dotsize)     if (inbox(x,y)) Dot(w,x,y,dotsize)
tomwalters@0: 
tomwalters@0: /* Max width and height (pixels) of chars in current font, (ref 6-17, 6-19) */
tomwalters@0: #define max_charwidth()         ( theFont->max_bounds.rbearing - theFont->min_bounds.lbearing )
tomwalters@0: #define max_charheight()        ( theFont->max_bounds.ascent + theFont->max_bounds.descent )
tomwalters@0: /* Number of lines and cols (chars) of current font which fit into box */
tomwalters@0: #define linespacing()           ( (theFont->max_bounds.descent)>>1 )
tomwalters@0: #define lineheight()            ( max_charheight()+linespacing() )
tomwalters@0: #define colwidth()              ( max_charwidth() )
tomwalters@0: #define nlines()                ( pheight() / lineheight() )
tomwalters@0: #define ncols()                 ( pwidth() / colwidth() )
tomwalters@0: #define topline(w,string)       lineString(w,string,1,1)
tomwalters@0: #define bottomline(w,string)    lineString(w,string,nlines(),1)
tomwalters@0: #define margin()                ( theFont->max_bounds.lbearing + theFont->max_bounds.rbearing )
tomwalters@0: #define headroom()              ( theFont->max_bounds.ascent )
tomwalters@0: #define leftmargin()            ( pleft() + margin() )
tomwalters@0: #define rightmargin()           ( pright() - margin() )
tomwalters@0: #define topmargin()             ( ptop() + headroom() )
tomwalters@0: #define bottommargin()          ( pbottom() - headroom() )
tomwalters@0: #define line(i)                 ( topmargin() + (i-1)*lineheight() )
tomwalters@0: #define col(j)                  ( leftmargin() + (j-1)*colwidth() )
tomwalters@0: #define lineString(w,string,i,j) ( XDrawString(theDisplay,w,theGC,col(j),line(i),string,strlen(string)) )
tomwalters@0: #define leftString(w,string,i)   ( XDrawString(theDisplay,w,theGC,leftmargin(),line(i),string,strlen(string)) )
tomwalters@0: #define rightString(w,string,i)  ( XDrawString(theDisplay,w,theGC,rightmargin()-stringwidth(string),line(i),string,strlen(string)) )
tomwalters@0: #define centreString(w,string,i) ( XDrawString(theDisplay,w,theGC,(pwidth()-stringwidth(string))>>1,line(i),string,strlen(string)) )
tomwalters@0: #define supertopline(w,string)   ( XDrawString(theDisplay,w,theGC,col(1),ptop()-max_charheight()-headroom(),string,strlen(string)) )
tomwalters@0: 
tomwalters@0: 
tomwalters@0: /****************************************************************************
tomwalters@0: *       Window parameters   (X11-specific).
tomwalters@0: ****************************************************************************/
tomwalters@0: Display        *theDisplay;
tomwalters@0: int             theScreen;        /* screen_number */
tomwalters@0: int             theWidth;         /* horizontal size, in pixels */
tomwalters@0: int             theHeight;        /* vertical size, in pixels */
tomwalters@0: unsigned long   theForeground;    /* lines, text, and border pixel value */
tomwalters@0: unsigned long   theBackground;    /* background pixel value */
tomwalters@0: GC              theGC;            /* graphics context */
tomwalters@0: XFontStruct    *theFont;          /* current font used to print text */
tomwalters@0: unsigned long   theBlack;         /* pixel value for black */
tomwalters@0: unsigned long   theWhite;         /* pixel value for white */
tomwalters@0: 
tomwalters@0: /****************************************************************************
tomwalters@0: *       System (global) variables
tomwalters@0: *****************************************************************************/
tomwalters@0: int     _xorg,  _yorg;  /* Window origin (pixel coords top-left wrt Display)*/
tomwalters@0: int     _width, _height;/* Window size (pixels).                            */
tomwalters@0: 
tomwalters@0: int     _Xp0,   _Yp0;   /* Box origin (pixel coords at bottom-left)         */
tomwalters@0: int     _Xp1,   _Yp1;   /* Box limits (pixel coords at top-right)           */
tomwalters@0: int     _Wb,    _Hb;    /* Box size (pixels).                               */
tomwalters@0: 
tomwalters@0: float   _Xd0,   _Yd0;   /* Box origin (data coords at bottom-left)          */
tomwalters@0: float   _Xd1,   _Yd1;   /* Box limits (data coords at top-right)            */
tomwalters@0: float   _xrange,_yrange;/* Box size (data ranges).                          */
tomwalters@0: 
tomwalters@0: int     _xshift,_yshift;/* Plot origin (pixel coords from box origin)       */
tomwalters@0: float   _xd0,   _yd0;   /* Data coords fixed at plot origin                 */
tomwalters@0: 
tomwalters@0: float   _xoffset,_yoffset;
tomwalters@0: float   _xscale, _yscale;
tomwalters@0: 
tomwalters@0: /****************************************************************************
tomwalters@0: *       Functions (in x11coord.c)
tomwalters@0: *****************************************************************************/
tomwalters@0: extern                  set_window_parameters();
tomwalters@0: extern                  set_box_parameters();
tomwalters@0: extern                  set_bordered_box();
tomwalters@0: extern                  set_data_parameters();
tomwalters@0: extern                  xopen();
tomwalters@0: extern  GC              initGC();
tomwalters@0: extern                  setLinewidth();
tomwalters@0: extern                  setFont();
tomwalters@0: extern  Window          xCreate();
tomwalters@0: extern                  axis();
tomwalters@0: extern                  box();
tomwalters@0: extern                  calibrate_Axis();
tomwalters@0: extern                  calibrate_Box();
tomwalters@0: extern                  plotX();
tomwalters@0: extern                  plotY();
tomwalters@0: extern  int             stringwidth();
tomwalters@0: extern  int             stringheight();
tomwalters@0: extern                  calibrate();
tomwalters@0: extern                  Dot();
tomwalters@0: