About how to add directional simulation in the pygsound

[xtgg4310]

Dear author:

I would like to know how to add directional simulation in the pygsound. I notice that parameter "Sounddirectivity" in Context.cpp can be set true. Also, in GSound/gsSoundDirectivity.cpp, it seems that several sound pattern has been defined in the program. So how can I set up the directional simulation method.

Best wishes.

[RoyJames]

It is possible. GSound has well-defined directivity described here

pygsound/src/GSound/gsound/gsSoundDirectivity.h

Lines 70 to 83 in 8f41cb1

	//********************************************************************************
	/// A class that represents a frequency-dependent directivity pattern for a directional sound source.
	/**
	* The directivity determines how sound is radiated from a source in all
	* directions for each frequency. The directivity is specified by providing
	* frequency response measurements for various directions. Internally, a
	* spherical harmonic representation is used to smoothly interpolate the
	* frequency responses for all directions. The directivity is sampled for
	* each sound path that is generated.
	*
	* The directivity is projected into the spherical harmonic basis whenever
	* it has been modified and is needed for a sound source. This operation is
	* slightly expensive (milliseconds), so only modify directivity when absolutely necessary.
	*/

But setting that flag to True only initializes an omnidirectional pattern which doesn't do anything, a specific pattern needs to be assigned following definitions in GSound/gsSoundDirectivity.cpp as you've noticed. For people who are familiar with C++, it should be easy to leverage this API. However, I have not exposed it in current python bindings just like many other functionalities that are less often used. I may not have the bandwidth to do these additions myself. But pull requests are welcome.

[xtgg4310]

Thanks for your answer, I have add a specific pattern in the program and simulate a directional acoustic wave. I want to know the definition of angle and theta in GSound/gsSoundDirectivity.cpp. I find the view direction of the source is -transform.orientioan.z. Does this mean that the value of theta and phi are corresponding to the z-axis?

[xtgg4310]

By the way, I just found that I fail to add a sound pattern to the source. I initialise the SoundSource with the pattern defined in the SoundDirectivity in gsSoundSource.cpp but get the same RIR. Is this operation right? Or should I realise other API about SoundDirectivity.

Best wishes.

[RoyJames]

By the way, I just found that I fail to add a sound pattern to the source. I initialise the SoundSource with the pattern defined in the SoundDirectivity in gsSoundSource.cpp but get the same RIR. Is this operation right? Or should I realise other API about SoundDirectivity.

Best wishes.

I cannot comment on this case without codes. My suggestion is to step into the key functions (or just print them out if you have difficulty setting up a debugger) to make sure that your new directivity is actually being called in the expected way.

Regarding coordinate convention - yes I believe the convention used throughout this project is ZYX in which -z is forward, +x is right, and +y is up.