Difference between revisions of "Development/Tutorials/Games/KALEngine"

Jump to: navigation, search
m (The Code: try to update explanations, need more work)
 
(27 intermediate revisions by 6 users not shown)
Line 23: Line 23:
  
 
==Abstract==
 
==Abstract==
Phonon is not really designed to handle multiple sounds at the same time. KALEngine is made for games and create one thread per sound, using the excellent openAL librairy. you also get all the other openAL goodness like 3D sounds, effects and multichannel.
+
Phonon is not really designed to handle multiple sounds at the same time. Gluon's audio module is made for games and create one thread per sound, using the openAL library. You also get all the other openAL goodness like 3D sounds, effects and multichannel.
  
==Installation==
+
== The Code ==
 +
In this example, we will play a simple sound file as "Hello Word".
  
1: Be sure you have installed dependent librairy.
+
<syntaxhighlight lang="cpp-qt">
- openAL ( sound api)
+
#include "audio/sound.h"
- alut (openal toolkit)
+
- libSndFile (load sound file).
+
  
2: compile and install kalengine from svn :
+
#include <QtCore/QDebug>
/trunk/playground/games/KALEngine/
+
  
== Hello Word ==
+
int main( int argc, char* argv[] )
 +
{
 +
    // create a sound object
 +
    GluonAudio::Sound* sound = new GluonAudio::Sound;
  
 +
    // load KDE's log in sound to the object
 +
    sound->load( "/usr/share/sounds/KDE-Sys-Log-In-Long.ogg" );
  
<code cppqt>
+
    // set sound volume, it can be between 0 and 1
 +
    sound->setVolume( 0.9 );
  
#include <KALEngine>
+
    // print the elapsed time until the sound has finished playing
#include <KALSource>
+
    qDebug() << "Playing sound with duration" << sound->duration() << "seconds.";
#include <KDebug>
+
  
int main(int argc, char **argv)
+
    // play the sound
{
+
    sound->play();
  
     KALEngine snd; //create an openAL object
+
     // wait until playing is finished
     snd.init(); // Initialize OpenAL Context + Device!
+
     while( sound->isPlaying() );
  
     KALSource *son = new KALSource(); // create a sample, if no argument, It will play an "hello world"
+
     // clear the buffer
     son->play(); // play the sound!!
+
     delete sound;
  
+
     return 0;
     while (son->getStatus() == AL_PLAYING) // wait while sound is playing
+
}
    {
+
</syntaxhighlight>
      kDebug()<<son->getElapsedTime(); //print the elapsed time.
+
    }
+
  
 +
- First, we create a GluonAudio::Sound. GluonAudio::Sound can be used for playing small sounds (shoot, scream, tic, walk, etc). It will load the entire file inside a buffer, so be careful if you try to play a big file using it.
  
    delete son; //when it finished! Don't forget to clear the buffer!!
+
If you want to try playing something else than KDE's log in sound, you can download a sample [http://ktank.free.fr/kalengine/ocean.wav ocean sound] and replace the sound load definition by:
    snd.shutdown(); // and close the device!!
+
  
 +
<syntaxhighlight lang="cpp-qt">
 +
    sound->load( "ocean.wav" );
 +
</syntaxhighlight>
 +
 +
You can only use it to play ogg or wav file at the moment, but we hope to bring more audio support soon.
 +
 +
- The sound can now be played by simply calling <b>play()</b>. This function is asynchronous, meaning your program doesn't have to wait until the sound has finished playing to continue.
 +
 +
- Then, to know when the sound has ended, we use <b>sound->isPlaying()</b>.
 +
 +
- Finally, we have to clear the GluonAudio::Sound buffer by deleting the GluonAudio::Sound pointer.
 +
 +
== Multi-channel ==
 +
 +
sound1->play();
 +
sound2->play();
 +
 +
...to develop
 +
== 3d sound ==
 +
 +
KALSource->setPosition(x,y,z)
 +
...to develop
  
    return 0;
 
}
 
  
 +
{{tip|For more information on how OpenAL works, see the documentation [[http://connect.creativelabs.com/openal/Documentation/OpenAL_Programmers_Guide.pdf OpenAL programmers Guide ]]}}
  
</code cppqt>
+
{{TODO|Create KALStream}}

Latest revision as of 20:00, 13 May 2013

KALEngine tutorial
Tutorial Series   KALEngine developement
Prerequisites   None
What's Next   Nothing at the moment
Further Reading   KGLEngine2d's code

Contents

[edit] Abstract

Phonon is not really designed to handle multiple sounds at the same time. Gluon's audio module is made for games and create one thread per sound, using the openAL library. You also get all the other openAL goodness like 3D sounds, effects and multichannel.

[edit] The Code

In this example, we will play a simple sound file as "Hello Word".

#include "audio/sound.h"
 
#include <QtCore/QDebug>
 
int main( int argc, char* argv[] )
{
    // create a sound object
    GluonAudio::Sound* sound = new GluonAudio::Sound;
 
    // load KDE's log in sound to the object
    sound->load( "/usr/share/sounds/KDE-Sys-Log-In-Long.ogg" );
 
    // set sound volume, it can be between 0 and 1
    sound->setVolume( 0.9 );
 
    // print the elapsed time until the sound has finished playing
    qDebug() << "Playing sound with duration" << sound->duration() << "seconds.";
 
    // play the sound
    sound->play();
 
    // wait until playing is finished
    while( sound->isPlaying() );
 
    // clear the buffer
    delete sound;
 
    return 0;
}

- First, we create a GluonAudio::Sound. GluonAudio::Sound can be used for playing small sounds (shoot, scream, tic, walk, etc). It will load the entire file inside a buffer, so be careful if you try to play a big file using it.

If you want to try playing something else than KDE's log in sound, you can download a sample ocean sound and replace the sound load definition by:

    sound->load( "ocean.wav" );

You can only use it to play ogg or wav file at the moment, but we hope to bring more audio support soon.

- The sound can now be played by simply calling play(). This function is asynchronous, meaning your program doesn't have to wait until the sound has finished playing to continue.

- Then, to know when the sound has ended, we use sound->isPlaying().

- Finally, we have to clear the GluonAudio::Sound buffer by deleting the GluonAudio::Sound pointer.

[edit] Multi-channel

sound1->play(); sound2->play();

...to develop

[edit] 3d sound

KALSource->setPosition(x,y,z) ...to develop


Ktip.png
 
Tip
For more information on how OpenAL works, see the documentation [OpenAL programmers Guide ]


noframe
 
TODO
Create KALStream

This page was last modified on 13 May 2013, at 20:00. This page has been accessed 7,149 times. Content is available under Creative Commons License SA 3.0 as well as the GNU Free Documentation License 1.2.
KDE® and the K Desktop Environment® logo are registered trademarks of KDE e.V.Legal