Wwise SDK 2022.1.7
The open architecture of Wwise supports different kinds of plug-ins:
Audio Plug-ins describe their model in the form of an XML file. This allows you to quickly change any of the settings of your plug-in, including default property values, without having to recompile the code. Properties described in this model are also used to provide a default graphical interface in the form of a properties table in Wwise if no custom GUI is provided by the plug-in.
The XML description file contains information about several aspects of a Wwise plug-in, including:
|Note: A Wwise plug-in dynamic library can contain multiple plug-ins (see Authoring Plug-in Library Format), each of which must be described in a single associated XML file.|
The XML description file for each Wwise plug-in dynamic library must have the same name as the dynamic library, except for the XML file extension and any lib prefix.
For example, if your dynamic library is named "MyPlugin.dll" or "libMyPlugin.dylib", then the plug-in description file must be named "MyPlugin.xml".
Below is an example of a simple plug-in XML description file.
Let's look at the various parts of the XML file in detail.
Let's look at the parts of this XML file's header and discuss them in detail.
The first line of any XML file defines the XML version and encoding. In this case, the XML version is 1.0, and the encoding is
UTF-8. The first line of any Wwise plug-in description file should always be exactly like the one above. The second line is an XML comment, in this case a copyright notice. You can introduce comments in various places in the XML file wherever necessary.
The main XML element in this document is named
PluginModule, and encloses all of the information for the various plug-ins defined in the file.
In the category of Audio plug-ins, there are three possible plug-in type elements:
EffectPlugin element is the main element for the definition of a single effect plug-in, while
SinkPlugin are the element names for source plug-ins and sink plug-ins, respectively.
|Note: If more than one plug-in is implemented in the dynamic library, the XML file will contain multiple plug-in elements. A dynamic library is not limited to a single type of audio plug-in.|
These elements contain three required attributes:
Name(mandatory): This string specifies the display name of the plug-in as it will appear in Wwise.
Two optional attributes can be specified:
SupportsIsSendModeEffect(optional): (Effect plug-in only) This boolean value indicates if the plug-in supports the send mode by querying
AK::IAkEffectPluginContext::IsSendModeEffect()during the initialization part. When
IsSendModeEffect()returns true, the plug-in should not output the dry signal and should ignore the dry level properties.
EngineDllName(optional): This string value overrides the name of the Sound Engine dynamic library to load at game runtime (by default it will be the same name as the XML). If
EngineDllNameis specified, ensure that both of your Sound Engine static and dynamic libraries share the same name. Providing a DLL/so file with your plug-in is necessary to be supported in commercial game engines such as Unity and Unreal 4. This does not affect the naming of the Authoring plug-in dynamic library, which should strictly correspond to the name of your XML file.
Wwise associates plug-in model definitions and plug-in implementations using numeral IDs. These IDs are provided in the XML description of each plug-in and in the plug-in descriptor in the plug-in library.
CompanyID is an ID corresponding to your organization. Three ranges exist:
PluginID is a unique numeral ID in the range 0-32767 that corresponds to a plug-in within a single organization.
For example, if you are developing plug-ins for in-house use only, you can pick any
CompanyID between 64 and 255, and any three PluginIDs between 0 and 32767. The numbers need not be sequential.
The CompanyID and PluginID need to be passed to the Sound Engine plug-in declaration macro
Caution: Important considerations:
For more details on IDs, refer to Wwise Plug-in IDs.
PluginInfo/PlatformSupport section defines the platforms supported by your plug-in. It can contain one or more
Platform elements, each of them specifying the various features supported by a plug-in on each platform. The following features can be specified:
CanBeInsertOnBussesdetermines whether the effect can be applied to control and master busses. Typically this will require the effect to support surround audio configuration.
CanBeInsertOnAuxBussesdetermines whether the effect can be applied to control and master auxiliary busses. Typically this will require the effect to support surround audio configuration. Note that if
CanBeInsertOnBussesis already set, the effect is already available on Aux busses.
CanBeInsertOnAudioObjectsdetermines whether the effect can be applied as insert to SFX (must support both mono and stereo processing).
CanBeRendereddetermines whether the effect can be used for offline rendering or not.
CanSendMonitorDatadetermines whether the effect can send monitoring data. Refer to
AK::Wwise::Plugin::Notifications::Monitor::NotifyMonitorDatafor more information.
CanBeSourceOnSounddetermines whether source plug-in can be a source for a sound.
CanBeInsertEndOfPipelinedetermines whether the effect can only be added at the end of the audio pipeline, which corresponds to the last effect slot of a top-level Audio Bus (reserved for Audiokinetic).
Your plug-in will be available only on the specified platforms within Wwise.
It is also possible to add the "Any" platform instead of listing every supported platform. Be aware though, this plug-in will then be advertised as being available on all platforms in Wwise and, if the plug-in does not provide the matching runtime libraries, the user will only notice it when porting it on this platform.
Each audio plug-in can define properties and references. For more information about properties and references, refer to Properties XML Description.
InnerTypes section defines the possible Inner Object Types that you can instantiate and use inside your plug-in. You can define multiple
InnerType inside the
InnerTypes section. Each
InnerType must have a unique name, and plug-in ID. The
InnerType section contains a
Properties section, in which you can define properties in the exact same way you would define plug-in properties.
The Inner Types are practical whenever you need to have multiple instances of an object in your plug-in. For example, you could define the Inner Type
Band for an EQ plug-in, when you have a variable number of EQ bands. Each band would have the same property definition, with different values for each band.
Note: The properties of Inner Types do not support RTPCs. Therefore, you can't use the
To manipulate the Inner Type instances (Inner Objects) in your plug-in code, you need to request the service by deriving
AK::Wwise::Plugin::RequestObjectStore in your plug-in class and using the
m_objectStore member. The
AK::Wwise::Plugin::ObjectStore interface provides functions for creating and deleting inner objects (
AK::Wwise::Plugin::ObjectStore::DeletePropertySet). Inner Objects' properties are manipulated using the PropertySet interface (see Property Set).
When objects are created, they must be stored in a named list using the insertion (
AK::Wwise::Plugin::ObjectStore::InsertPropertySet) and removal (
AK::Wwise::Plugin::ObjectStore::RemovePropertySet) functions. For example, you could create an inner object of type
Band, and store it in the
|Note: An inner object can only be stored in a single list at any one time.|
The persistence in the project Work Units is automatically handled by Wwise. However, you must implement the serialization of the inner objects in the SoundBanks and for the Sound Engine data. You must serialize the inner objects inside
When you add inner objects to the object store, the associated Undo mechanism is automatically created in Wwise. You don't need to implement the undo system on your side. However, to support undo events correctly, you need to update your user interface only at the reception of notifications from the framework.
AK::Wwise::Plugin::NotificationsObjectStore provides handlers to override that allow to act on notification events related to inner objects. These are primarily meant to update custom GUI elements on model changes that could be triggered by a user interaction, an undo event or even a WAAPI call.
For example, after calling
AK::Wwise::Plugin::ObjectStore::InsertPropertySet, do not update the UI right-away. Wait for the notification
AK::Wwise::Plugin::NotificationsObjectStore::NotifyInnerObjectAddedRemoved to be called on your plug-in. This notification tells you that an object was added or removed from a list.
Similarly, you can react on
AK::Wwise::Plugin::NotificationsObjectStore::NotifyInnerObjectPropertyChanged, which is called when the value of a property changes in an inner object.
Refer to the Wwise Source and Effect Plug-in Troubleshooting Guide if you run into any problems.