LOVE/megasource
1
0
Fork 0
mirror of https://github.com/love2d/megasource.git synced 2026-08-19 20:20:11 +02:00
Code Issues Packages Projects Releases Wiki Activity

Update OpenAL-soft to 1.21.1

Browse Source
This commit is contained in:
Miku AuahDark
2021-02-11 18:04:50 +08:00
parent 08f227997e
commit 904cc75ba8
358 changed files with 61122 additions and 60973 deletions
Download Patch File Download Diff File Expand all files Collapse all files
libs/openal-soft/docs/ambisonics.txt
+16 -23
View File
@@ -79,30 +79,23 @@ Soft (or any other OpenAL implementation that wishes to) can render using
Ambisonics and decode the ambisonic mix for a high level of accuracy over what
simple pan-pot could provide.
This is effectively what the high-quality mode option does, when given an
appropriate decoder configuation for the playback channel layout. 3D rendering
and effect mixing is done to an ambisonic buffer, which is later decoded for
output utilizing the benefits available to ambisonic processing.
When given an appropriate decoder configuration for the channel layout, the
ambisonic mix can be decoded utilizing the benefits available to ambisonic
processing, including frequency-dependent processing and near-field effects.
Without a decoder configuration, the ambisonic mix can still be decoded for
good stereo or surround sound output, although without near-field effects as
there's no speaker distance information.
The basic, non-high-quality, renderer uses similar principles, however it skips
the frequency-dependent processing (so low frequency sounds are treated the
same as high frequency sounds) and does some creative manipulation of the
involved math to skip the intermediate ambisonic buffer, rendering more
directly to the output while still taking advantage of all the available
speakers to reconstruct the sound wave. This method trades away some playback
quality for less memory and processor usage.
In addition to providing good support for surround sound playback, Ambisonics
also has benefits with stereo output. 2-channel UHJ is a stereo-compatible
format that encodes some surround sound information using a wide-band 90-degree
phase shift filter. It works by taking a B-Format signal, and deriving a
frontal stereo mix with the rear sounds attenuated and filtered in with it.
Although the result is not as good as 3-channel (2D) B-Format, it has the
distinct advantage of only using 2 channels and being compatible with stereo
output. This means it will sound just fine when played as-is through a normal
stereo device, or it may optionally be fed to a properly configured surround
sound receiver which can extract the encoded information and restore some of
the original surround sound signal.
In addition to surround sound output, Ambisonics also has benefits with stereo
output. 2-channel UHJ is a stereo-compatible format that encodes some surround
sound information using a wide-band 90-degree phase shift filter. This is
generated by taking the ambisonic mix and deriving a front-stereo mix with
with the rear sounds filtered in with it. Although the result is not as good as
3-channel (2D) B-Format, it has the distinct advantage of only using 2 channels
and being compatible with stereo output. This means it will sound just fine
when played as-is through a normal stereo device, or it may optionally be fed
to a properly configured surround sound receiver which can extract the encoded
information and restore some of the original surround sound signal.
What Are Its Limitations?