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[Java-game-lib-cvs] CVS: LWJGL/doc openal_c-to-java.html,NONE,1.1 openal_c-to-java.txt,1.1,NONE
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From: Brian M. <ma...@us...> - 2002-09-09 16:41:42
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Update of /cvsroot/java-game-lib/LWJGL/doc In directory usw-pr-cvs1:/tmp/cvs-serv29338a Added Files: openal_c-to-java.html Removed Files: openal_c-to-java.txt Log Message: mod: changed text file to html, so that it can be included on website --- NEW FILE: openal_c-to-java.html --- CVS Browser: http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/java-game-lib/LWJGL/doc/openal_c-to-java.html <!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">Array Conversion<br> <font size="-1">(by Brian Matzon <<a href="mailto:br...@ma...">br...@ma...</a>>)</font><br> </h1> <b>1.0 About this document</b><br> This document describes the typical rules for converting arrays often used in C/C++ OpenAL (and indeed OpenGL too) code.<br> It is not bullet proof, but should handle most cases.<br> <br> <b>1.1 Array to ByteBuffer<br> </b>When using an array of some data type in C/C++ you will typically convert that<br> to the corresponding ByteBuffer type. ie:<p style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt>ALfloat floatv[3];</tt></p> <p>becomes</p> <p style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt> FloatBuffer floatv = createFloatBuffer(3);</tt></p> <p>In this example, <tt>createFloatBuffer</tt> is this utility method:</p> <p style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt> public FloatBuffer createFloatBuffer(int size) {<br> //allocate bytebuffer, using 4 bytes per float<br> ByteBuffer temp = ByteBuffer.allocateDirect(4*size);<br> temp.order(ByteOrder.nativeOrder());<br> <br> return temp.asFloatBuffer();<br> }</tt></p> <p> <b>1.2 Examples</b><br> Using the above FloatBuffer, you would typically use it like this (examples taken from altest.c/ALTest.java):</p> <p> <b>1.2.1 Example 1</b></p> <p style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt> alGetListenerfv(AL_POSITION, floatv);</tt></p> <p> becomes</p> <p style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt> al.getListenerfv(AL.POSITION, Sys.getDirectBufferAddress(floatv));</tt></p> <p><b>1.2.2 Example 2</b></p> <p style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt> if (floatv[0] != 100.0)) {</tt></p> <p>becomes:</p> <p style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt> if (floatv.get(0) != 100.0f) {</tt></p> <p><b>1.2.3 Example 3</b></p> <p style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt> alGetListener3f(AL_POSITION, &floatv[0], <br> &floatv[1], <br> &floatv[2]);</tt></p> <p>becomes</p> <p style="border-style: solid; border-width: 1px; padding: 3px; background-color: rgb(255,255,204);"><tt> al.getListener3f(AL.POSITION, Sys.getDirectBufferAddress(floatv), <br> Sys.getDirectBufferAddress(floatv) + 4, <br> Sys.getDirectBufferAddress(floatv) + 8);</tt></p> <p>the last case is a bit special, since we start of by getting the base address of the buffer, and then add the datatype size to the base address<br> to get the address of that specific index. This is just how it has to be in Java.</p> </body> </html> --- openal_c-to-java.txt DELETED --- CVS Browser: http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/java-game-lib/LWJGL/doc/openal_c-to-java.txt |
