A Simple Example

The following source code can be used to start the development of XY application.

The Application

The aim of the test program is to draw the graph below.

Remark: In this application, the IUP widget toolkit will be used only to offer menus, buttons and canvases. The IUP canvas will be associated to a CD device, where the graph will be drawn.

The Source Code

As a start, programmers should declare que include files needed.

#include "iup.h"         // IUP
#include "cd.h"          // CD
#include "cdiup.h"       // IUP + CD
#include "xy.h"          // XY
#include "xyserfil.h"    // my own series

To define the titles, just declare two text objects:

XYText tipo_de_curva(
         "Curva de Destilação",
         XY_BLACK, 
         XYText::large, 
         XYText::helvetica, 
         XYText::italic, 
         XYText::north, 
         XYText::horizontal, 
         xytrue);

XYText periodo(
         "Amostra do Mês de Junho/96", 
         XY_BLUE, 
         XYText::standard, 
         XYText::timesRoman, 
         XYText::bold, 
         XYText::north, 
         XYText::horizontal);

The Axes Definition

Then, the axes should be declared (linear). Note that some definitions should be made before! They correspond to the axes' titles and decorator scales.

	The titles are text objects (just like stated before).
	The decorators specify the numeric, date/time or string format associated to values.As the decorators refer to string transformation, it should be associated to a scale text object. So, these text objects should be defined before!

// Defining text scales...
XYText escala_porcentagem(
       XY_BLACK, 
       XYText::small, 
       XYText::timesRoman, 
       XYText::plain, 
       XYText::north, 
       XYText::horizontal);
 
XYText escala_temperatura(
       XY_BLACK, 
       XYText::small, 
       XYText::timesRoman, 
       XYText::plain, 
       XYText::east,  
       XYText::horizontal);

// Defining scales... (0.1 precision)
XYNumericalScaleDecorator decorador_porcentagem(
       "%.1f", &escala_porcentagem);
XYNumericalScaleDecorator decorador_temperatura(
       "%.1f", &escala_temperatura);

// Defining titles...
XYText tit_porcentagem (
        "Porcentagem (%)", 
        0.5, 0.15, 
        XY_RED, 
        XYText::standard, 
        XYText::timesRoman, 
        XYText::plain, 
        XYText::center, 
        XYText::horizontal);
 
XYText tit_temperatura (
        "Graus Centígrados", 
        0.03, 0.5, 
        XY_RED, 
        XYText::standard, 
        XYText::timesRoman,
        XYText::plain, 
        XYText::center, 
        XYText::vertBotTop);

// Finally, defining axes...
XYLinearAxis eixo_porcentagem(
        0.0, 96.0, 
        0.11, 0.2, 
        XY_RED, 
        0.7,  
        0.0, 
        4., 
        &decorator_porcentagem,
        &tit_porcentagem);

XYLinearAxis eixo_temperatura(
        -300, 950, 
        0.11, 0.2, 
        XY_RED, 
        0.6, 
        90.0, 
        50., 
        &decorator_temperatura,
        &tit_temperatura);

The Grids

Then, the programmer can set two grid objects that will be plot inside the graph. Each grid is associated to one direction (horizontal or vertical).

XYGrid grv (   0.,  96.,    0., XY_GRAY,  0.,  4.);
XYGrid grh (-300., 950., -300., XY_GRAY, 90., 50.);

The Curve

After the axes definition, the new curve can be assingned to them. This definition is divided in two parts:

	series definition - a XYSerie object should be created. This object provides the data set.
	mask definition - the data representation (lines, marks etc).

The Series

In our example, the data set is represented by the variable arquivo, provided by the class XYSeriesFile. Check others tutorial sections fo detailed explanation on how building application series.

// this object will ready the content of "dado.dat" file
XYSeriesFile arquivo ("dado.dat");

The Mask

For this application, a simple line mask is set with three attributes: a title, a series and two axes.

	The title is a common text object (created for this purpose). This text is used at the graph legend.
	The series is the arquivo variable.
	The axes were already described before.

// Defining the curve title...
XYText mask_titulo(
          "Óleo CRU",
          XY_BLACK, 
          XYText::tile, 
          XYText::timesRoman, 
          XYText::plain, 
          XYText::north, 
          XYText::horizontal);

// Defining line mask
XYCartesianLineMask marquivo(
          &mask_titulo,                         // title
          &arquivo,                             // series
          &eixo_porcentagem, &eixo_temperatura, // axes
          XY_RED,      
          1, 
          XYCartesianLineMask::continuous);

The Legend

A legend can construted with a simple constructor.

XYLegend legend (0.83, 0.3, 1, 1);

The Graph

At last, the graph can be defined. This time, the constructor is called inside the main function. Then, the following declaration builds only a pointer.

XYCartesian* grafico = NULL;

The Repaint Callback

After the graph construction, a special redraw callback should be set to force a graph repaint when the IUP/CD canvas is exposed. The following function uses the IUP callback paradigm: It clears and redraw the graph.

int frepaint (Ihandle *) {
   grafico->clear();
   grafico->draw();
   return IUP_DEFAULT;
}

The Main Function

void main(void){ 
   // Initializing IUP anda building a simple dialog...
   IupOpen ();
   Ihandle *c = IupCanvas ("arepaint");
   Ihandle *d = IupDialog (c);
   IupSetAttributes (d," SIZE = 400x300, TITLE = XY++");
   IupSetFunction ("arepaint", (Icallback) frepaint);
   IupMap(d);

   // Constructing the graph:
   // Association to "c": the IUP canvas
   // Assoctiation to the grids declared before
   grafico = new XYCartesian (c, 0.0, 0.0, 1.0, 1.0, &grv, &grh);

   // Setting titles...
   grafico->insert (&período);
   grafico->insert (&tipo_de_curva);

   // Setting colors...
   grafico->color (XY_GRAY);

   // Inserting axes...
   grafico->insert (&eixo_temperatura);
   grafico->insert (&eixo_porcentagem);
   
   // Calculating the mask area (after the axes definition and insertion)
   grafico->calcMaskArea (0);

   // Setting mask area color
   grafico->maskAreaColor (XY_WHITE);

   // Inserting the curve (mask).
   // Remember: the mask is already associated to a constructed series (arquivo)
   grafico->insert (&marquivo);

   // Defining the legend...
   grafico->legend (&legend);

   // IUP call: exposing the main dialog ("d")...
   // Entering IUP event loop. If the loop ends, the application is down!
   IupShow (d);
   IupMainLoop ();
   IupClose ();
}