<html> <head> <!-- __CINERA_INCLUDES__ --> </head> <body> <div> <!-- __CINERA_MENUS__ --> <!-- __CINERA_PLAYER__ --> </div> <!-- __CINERA_SCRIPT__ --> <article id="video-notes"> <h1><!-- __CINERA_TITLE__ --></h1> <h3 id="input-cleanup-and-fixes">Input Cleanup and Fixes</h3> <p>This episode starts with some cleanup and fixes to the input handling code from yesterday.</p> <ul> <li>Windows API often uses a <code>0</code> return value to indicate success. Our stubs probably shouldn't return <code>0</code>.</li> <li>Windows 8 ships with <code>xinput1_4.dll</code> only. So we need to try each version in turn</li> <li>When you handle WM_SYSKEY* messages, you lose built in Alt-F4 functionality, and have to reimplement it.</li> </ul> <h3 id="sound-programming-for-games">Sound Programming for Games</h3> <p>Casey starts with a high level overview of sound programing for games. The key ideas here are that we are allocating a <a href="http://en.wikipedia.org/wiki/Circular_buffer">circular buffer</a> for sound, and the system will play it continually on a loop. If you haven't worked with circular buffers (or ring buffers) before, much of this code will be confusing. It's worth taking some time to familiarize yourself with them.</p> <p>Resources:</p> <ul> <li><a href="http://c.learncodethehardway.org/book/ex44.html">Ring Buffers</a> on "Learn C The Hard Way"</li> </ul> <h3 id="working-with-directsound">Working with DirectSound</h3> <p>The basic process for initializing DirectSound is as follows:</p> <ol> <li>Load the Library - <a href="http://msdn.microsoft.com/en-us/library/ms684175.aspx"><code>LoadLibrary</code></a><code>("dsound.dll")</code></li> <li>Create a DirectSound object - <a href="http://msdn.microsoft.com/en-us/library/microsoft.directx_sdk.reference.directsoundcreate8.aspx"><code>DirectSoundCreate()</code></a></li> <li>Set the Cooperative Level - <a href="http://msdn.microsoft.com/en-us/library/microsoft.directx_sdk.idirectsound8.idirectsound8.setcooperativelevel.aspx"><code>IDirectSound8::SetCooperativeLevel()</code></a></li> <li>"Create" a primary buffer - <a href="http://msdn.microsoft.com/en-us/library/microsoft.directx_sdk.idirectsound8.idirectsound8.createsoundbuffer.aspx"><code>IDirectSound8::CreateSoundBuffer()</code></a></li> <li>Create a secondary buffer</li> <li>Tell DirectSound to start playing the secondary buffer - <a href="http://msdn.microsoft.com/en-us/library/microsoft.directx_sdk.idirectsoundbuffer8.idirectsoundbuffer8.play.aspx"><code>IDirectSoundBuffer8::Play()</code></a></li> </ol> <p>In the next episode we will look closely at how to fill this buffer and implement it in the game loop.</p> </article> </body> </html>