Sample code

This section provides examples of the GUIDO library use.

Displaying a score

 
#include <iostream>
 
#include "GUIDOEngine.h"
#include "GDevicePostScript.h"
 
using namespace std;
// ---------------------------------------------------------------------------
//  This example of code is intended to show the minimum steps to read a
//  GMN file and to display it.
//  Take care that for simplicity, this example doesn't check return codes
// ---------------------------------------------------------------------------
void DrawGMNFile (const char * filename) 
{
    ARHandler arh;
    // use a GDevicePostScript with a 72 dpi resolution
    GDevicePostScript dev ((int)(21*72/2.54), (int)(29.7*72/2.54), "outfile.eps", "", "");
    
    // declare a data structure for engine initialisation
    // we'll make use of the default graphic device (embedded in the library)
    // Guido font is guido2 and text font is times
    GuidoInitDesc gd = { &dev, 0, "guido2", "Times" };
    GuidoOnDrawDesc desc;              // declare a data structure for drawing        
    GuidoInit (&gd);                   // Initialise the Guido Engine first
    
    // and parse the GMN file to get a GGR handle directly stored in the drawing struct
    GuidoParseFile (filename, &arh);
    GuidoAR2GR (arh, 0, &desc.handle);
    desc.hdc = &dev;                    // we'll draw on the postscript device
    desc.page = 1;                      // draw the first page only
    desc.updateRegion.erase = true;     // and draw everything
    desc.scrollx = desc.scrolly = 0;    // from the upper left page corner
    desc.sizex = desc.sizey = 500;      // size of the drawing region
    
    GuidoOnDraw (&desc);
}
 
int main(int argc, char **argv)
{
    const char * file = argv[1];
    DrawGMNFile (file);
    return 0;
}

Building music using the GUIDO Factory

 
#include "GUIDOFactory.h"
 
// ---------------------------------------------------------------------------
//  Guido Factory example of use
//  Take care that for simplicity, this example doesn't check return codes
// ---------------------------------------------------------------------------
void TestGuidoFactory() 
{
    ARHandler ar; GRHandler gr;
    ARFactoryHandler *f;
    
    GuidoFactoryOpen(&f);               // open the GUIDO Factory first
    
    GuidoFactoryOpenMusic(f);           // and create a new score   
    GuidoFactoryOpenVoice(f);           // open a new voice
 
    GuidoFactoryOpenEvent(f, "c" );     // open a new note
    GuidoFactoryCloseEvent(f);          // close the note which is now part of the opened voice
    
    GuidoFactoryOpenEvent(f, "e" );     // open another new note
    GuidoFactoryAddSharp(f);            // add a sharp to the opened note
    GuidoFactoryCloseEvent(f);          // and close the note which is now part of the opened voice
 
    GuidoFactoryCloseVoice(f);          // close the voice which is now part of the opened score
 
    
    GuidoFactoryOpenVoice(f);           // open a second voice
    GuidoFactoryOpenEvent(f, "a" );     // open a new voice
    GuidoFactoryAddFlat(f);             // add a flat to the opened note
    GuidoFactoryCloseEvent(f);          // and close the note which is now part of the second voice
 
    GuidoFactoryOpenEvent(f, "d" );     // open another new note
    GuidoFactoryCloseEvent(f);          // and close the note which is now part of the second voice
 
    GuidoFactoryCloseVoice(f);          // close the voice which is now part of the opened score
    
    // - Extract AR and GR
    ar = GuidoFactoryCloseMusic(f);     // extract the GAR handle
    GuidoAR2GR( ar, 0, &gr );           // and the GGR handle
    GuidoFactoryClose(f);               // close the GUIDO Factory which won't be used any more
 
    if( gr )                            // check for the handle validity
    {
        // ... Do something with the GGR handle (i.e: draw)
    }
}