initial import of tutorial
This commit is contained in:
Brian Matzon
parent
66ca843a0c
commit
453658d995
|
|
@ -0,0 +1,208 @@
|
|||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
|
||||
<html>
|
||||
<head>
|
||||
<title>OpenAL Tutoral</title>
|
||||
|
||||
<meta http-equiv="content-type"
|
||||
content="text/html; charset=windows-1252">
|
||||
<meta name="author" content="Brian Matzon">
|
||||
<meta name="description" content="Basic sound using OpenAL">
|
||||
</head>
|
||||
<body>
|
||||
<h1 align="center">OpenAL Tutorial<br>
|
||||
<font size="-1">(by Brian Matzon <<a href="mailto:brian@matzon.dk">brian@matzon.dk</a>>)</font><br>
|
||||
</h1>
|
||||
<b>1.0 OpenAL Basics</b><br>
|
||||
Before embarking on our little OpenAL adventure, some tools are needed.<br>
|
||||
<br>
|
||||
<b>1.0.1 Ingredients</b><br>
|
||||
Head on over to Creatives <a
|
||||
href="http://developer.creative.com/scripts/DC_D&H_Games-Downloads.asp?opt=2">site</a>
|
||||
and snag a copy of the OpenAL specification along with a copy of the Programmers
|
||||
reference.<br>
|
||||
If you haven't already done so, get a copy of the OpenAL runtime environment
|
||||
too (and install it).<br>
|
||||
<br>
|
||||
<b>1.1 OpenAL theory</b><br>
|
||||
Uhm... I'm not going to write this... In all honesty reading the specification
|
||||
would be a good thing before continuing - but it isn't required...<br>
|
||||
<br>
|
||||
<b>1.2 Basic setup</b><br>
|
||||
Lets start out by creating a skeleton class for some very basic sound. We'll
|
||||
start of by creating the required OpenAL objects<br>
|
||||
<p
|
||||
style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt>import
|
||||
org.lwjgl.openal.AL;<br>
|
||||
import org.lwjgl.openal.ALC;<br>
|
||||
import org.lwjgl.openal.ALCcontext;<br>
|
||||
import org.lwjgl.openal.ALCdevice;<br>
|
||||
import org.lwjgl.openal.ALUT;<code></code><br>
|
||||
<br>
|
||||
public class PlayTest {<br>
|
||||
<br>
|
||||
/** OpenAL instance */<br>
|
||||
protected AL al;<br>
|
||||
<br>
|
||||
/** OpenAL Context instance */<br>
|
||||
protected ALC alc;<br>
|
||||
<br>
|
||||
/** OpenAL Util library instance */<br>
|
||||
protected ALUT alut;<br>
|
||||
<br>
|
||||
/** OpenAL context */<br>
|
||||
protected ALCcontext context;<br>
|
||||
<br>
|
||||
/** OpenAL device */<br>
|
||||
protected ALCdevice device; <br>
|
||||
<br>
|
||||
/**<br>
|
||||
* Creates an instance of PlayTest<br>
|
||||
*/<br>
|
||||
public PlayTest() {<br>
|
||||
try {<br>
|
||||
</tt> <tt> al = new AL();<br>
|
||||
alc = new ALC();<br>
|
||||
alut = new ALUT();<br>
|
||||
<br>
|
||||
al.create();<br>
|
||||
alc.create();<br>
|
||||
alut.create();<br>
|
||||
} catch (Exception e) {<br>
|
||||
e.printStackTrace();<br>
|
||||
}</tt><tt><br>
|
||||
}<br>
|
||||
}</tt><code></code></p>
|
||||
We need instances of the following classes:<br>
|
||||
<ul>
|
||||
<li><tt>AL </tt>- basic source, buffer and listener interaction</li>
|
||||
<li><tt>ALC </tt>- context and device creatiuon</li>
|
||||
<li><tt>ALUT </tt>- OpenAL utility class</li>
|
||||
</ul>
|
||||
<b>1.3 OpenAL initialization</b><br>
|
||||
Now that we have created a basic class containing instances of the relevant
|
||||
OpenAL classes, lets start of by initializing OpenAL - that is create a device
|
||||
and a context:<br>
|
||||
<p
|
||||
style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"> <tt>
|
||||
/**<br>
|
||||
* Initializes OpenAL<br>
|
||||
*/<br>
|
||||
protected void alInitialize() { <br>
|
||||
//get default device<br>
|
||||
device = alc.openDevice(null);<br>
|
||||
<br>
|
||||
//create context (no attributes specified)<br>
|
||||
context = alc.createContext(device, 0);<br>
|
||||
<br>
|
||||
//make context current<br>
|
||||
alc.makeContextCurrent(context);<br>
|
||||
}</tt><code><br>
|
||||
</code></p>
|
||||
Start of by opening a device using the <tt>openDevice </tt>method. <tt>openDevice
|
||||
</tt>takes a <tt>String </tt>as argument, containing the name of the device
|
||||
to open. If no name is supplied, the default device will be used (OpenAL
|
||||
currently doesn't support enumeration of devices available).<br>
|
||||
<br>
|
||||
Having opened a device, create a context to that device using <tt>createContext</tt>.
|
||||
<tt>createContext</tt> takes two arguments: device to use and a list of attributes
|
||||
(see specification for list of attributes). Since we're going by default context,
|
||||
we just specify <tt>0</tt> for attributes.<br>
|
||||
<br>
|
||||
Finish of by making the created context current. Do this by calling <tt>makeContextCurrent</tt>,
|
||||
supplying just created context as argument.<br>
|
||||
<p><b>1.4 Buffer and Source creation</b><br>
|
||||
Now that we have opened a device and gotten a context, we need to create
|
||||
two things to actually get some sound. We need to create a buffer to hold
|
||||
sounddata, and a source that is to play the sounddata.<br>
|
||||
Lets start of by creating one source, and one buffer:</p>
|
||||
<p
|
||||
style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt>
|
||||
//create one IntBuffer as buffer and one as source<br>
|
||||
IntBuffer buffers = createIntBuffer(1);<br>
|
||||
IntBuffer sources = createIntBuffer(1);<br>
|
||||
<br>
|
||||
//generate buffers and sources<br>
|
||||
al.genBuffers(1, Sys.getDirectBufferAddress(buffers));<br>
|
||||
al.genSources(1, Sys.getDirectBufferAddress(sources));</tt></p>
|
||||
<p>There, all set for actually loading some sounddata into the buffer.<br>
|
||||
</p>
|
||||
<b>1.5 Loading sounddata and setting up a buffer</b><br>
|
||||
Now that we have a buffer, we need to load some sound data into this buffer.
|
||||
This is done using the <tt>al.bufferData</tt> method. In our example we will
|
||||
cheat a bit, by using the <tt>ALUT </tt>method <tt>loadWAVFile</tt> to load
|
||||
a wave file, and copy this into the buffer:<br>
|
||||
<p
|
||||
style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt>
|
||||
//load wave data<br>
|
||||
ALUTLoadWAVData file = alut.loadWAVFile("myfile.wav");<br>
|
||||
<br>
|
||||
//copy to buffer<br>
|
||||
al.bufferData(buffers.get(0), file.format, file.data, file.size, file.freq);<br>
|
||||
<br>
|
||||
//unload file again<br>
|
||||
alut.unloadWAV(file.format, file.data, file.size, file.freq); <br>
|
||||
</tt></p>
|
||||
Having loaded the data, we pass it to <tt>bufferData</tt>. Once the buffer
|
||||
has been filled with sounddata, we unload it from the system using <tt>alut.unloadWAV</tt>.
|
||||
Don't worry about deleting it this soon - the sounddata has been <b>copied</b>
|
||||
to the buffer.<br>
|
||||
<br>
|
||||
<b>1.6 Associating sources and buffers</b><br>
|
||||
To associate a source to a buffer we set the integer BUFFER attribute on
|
||||
the source, and assign it a value of the buffer to play:<br>
|
||||
<p
|
||||
style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt>
|
||||
//set up source input<br>
|
||||
al.sourcei(sources.get(0), AL.BUFFER, buffers.get(0));</tt><tt><br>
|
||||
</tt></p>
|
||||
<b>1.7 Setting source properties</b><br>
|
||||
Having set up the source, it is time to set some attributes on the source
|
||||
- there are many that can be set, but in this example we only set the looping
|
||||
attribute to true by doing the following:<br>
|
||||
<p
|
||||
style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt>
|
||||
//loop source<br>
|
||||
al.sourcei(sources.get(0), AL.LOOPING, AL.TRUE);</tt><tt><br>
|
||||
</tt></p>
|
||||
<b>1.8 Sound...<br>
|
||||
</b>There, ready to play the sound, do this using the <tt>sourcePlay </tt>method
|
||||
of the <tt>AL </tt>class. to stop and pause use <tt>sourcePause </tt>and
|
||||
<tt>sourceStop </tt>respectively, and supply the source to affect:<br>
|
||||
<p
|
||||
style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt>
|
||||
//play source 0<br>
|
||||
al.sourcePlay(sources.get(0));<br>
|
||||
<br>
|
||||
//wait 5 secs<br>
|
||||
try {<br>
|
||||
System.out.println("Waiting 5 seconds for sound to complete");<br>
|
||||
Thread.sleep(5000);<br>
|
||||
} catch (InterruptedException inte) {<br>
|
||||
}<br>
|
||||
<br>
|
||||
//stop source 0<br>
|
||||
al.sourceStop(sources.get(0));</tt></p>
|
||||
<b>1.9 Cleaning up<br>
|
||||
</b>Having had loads of fun playing a sound (!), it is now time to do some
|
||||
house chores. We need to clean up what we have created, this amounts to:<br>
|
||||
- deleting source and buffer<br>
|
||||
- deleting context<br>
|
||||
- closing devce<br>
|
||||
as is shown here:<b><br>
|
||||
</b>
|
||||
<p
|
||||
style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt>
|
||||
//delete buffers and sources<br>
|
||||
al.deleteSources(1, Sys.getDirectBufferAddress(sources));<br>
|
||||
al.deleteBuffers(1, Sys.getDirectBufferAddress(buffers));<br>
|
||||
<br>
|
||||
//shutdown<br>
|
||||
alc.makeContextCurrent(null);<br>
|
||||
alc.destroyContext(context);<br>
|
||||
alc.closeDevice(device);</tt></p>
|
||||
There, all set. Now you should be able to play some basic sound!<br>
|
||||
This tutorial is rather short, and the above examples feature no error checking.
|
||||
For the complete source code, look at:<br>
|
||||
<tt>org.lwjgl.openal.BasicTest</tt> in the repository.<br>
|
||||
</body>
|
||||
</html>
|
||||
Loading…
Reference in New Issue