/dsoal

A DirectSound DLL replacer that enables surround sound, HRTF, and EAX support via OpenAL Soft

Primary LanguageCGNU Lesser General Public License v2.1LGPL-2.1

DSOAL

This project is for a DirectSound DLL replacement. It implements the DirectSound interfaces by translating the calls to OpenAL, and fools applications into thinking there is a hardware accelerated sound device. EAX is also implemented (up to version 4) by using OpenAL's EAX extension, allowing for environmental reverb with sound obstruction and occlusion effects.

Effectively, this allows DirectSound applications to enable their DirectSound3D acceleration path, and turn on EAX. The actual processing is being done by OpenAL with no hardware acceleration requirement, allowing it to work on systems where audio acceleration is not otherwise available.

Or more succinctly: it enables DirectSound3D surround sound and EAX for systems without the requisite hardware.

Source Code

To build the source, you will need CMake 2.6 or newer. You can either use the CMake GUI, specifying the directories for the source and where the build files should go, or using one of the command-line programs, for example by first making sure to be in an empty directory where the build files will go (such as the provided build/ sub-directory) and running cmake with the path to the source.

Once successfully built, it should have created dsound.dll.

Usage

Once built, copy dsound.dll to the same location as the desired application's executable. You must also provide an OpenAL DLL in the same location, named as dsoal-aldrv.dll, or else the DLL will fail to work. Some applications may need to be configured to use DirectSound3D acceleration and EAX, but it otherwise goes to work the next time the application is run.

Source releases and Windows binaries for OpenAL Soft are available at its homepage. Instructions are also provided there.

Environment Variables

The following environment variables can be set:

  • DSOAL_LOGLEVEL:
    • Values: Integer, range 0-3
    • Description: Set the verbosity of DSOAL logging. Level 3 enables logging of API traces. By default, a log level of 1 is used to report errors only.
  • DSOAL_LOGFILE:
    • Values: String
    • Description: Path to a file that will be created/overwritten by DSOAL on each execution. All logging will be redirected to that file. If unset, logging it written to the process's stderr output.