So how exactly does the processed 3D hardware accelerated sound from the GPU it's getting forwarded to the dedicated sound card? Thanks/
I ignored something obvious in my last post...and probably where ray traced audio is executed: at the top of the stack in the application layer. The game itself would use it's knowledge of the environment and the sources of the sound to play the PCM and bounce the audio around to the player's position where the theoretical signals that the reach the player are sent into the audio stack as PCM.
It stands to reason that you wouldn't want *any* environmental audio effects enabled in the audio engine nor the hardware if you're using ray traced audio because the sounds are pre-processed for environmental effects.
Sound card has no idea that the PCM it is receiving was ray traced unless something is added to the audio stack the flags it as such.
It needs to be duly noted that ray tracing sound is far more complex than ray tracing light because sound is a pressure wave, not radiation. Pressure waves need to calculate for density (air and object) rather than reflectivity. Where ray tracing light can work based off of meshes games already use (just need to assign a reflectivity to each mesh), ray tracing sound requires (unless they cheat, then what's the point?) 3D modeling of spaces the player can't see. For example, the cavities in a studded, sheetrock wall will create a different sound profile than a wall of bricks. Further, the thickness of both can hugely vary what the sound is like especially on the other side.
Imagine 6 panes of glass in a line, one after the other, in a sound deadening box. You clap your hands in front of the first while recording the sound after each one. Each pane of glass makes it sound different because sound is vibrations. By the time you reach the last pane, there is nothing at all. Simply designing a house with double or triple paned glass, gas filled or not, noticeably changes the sound profile.
Said differently: ray tracing light is very expensive on hardware but relatively cheap for developers. Ray tracing sound is relatively cheap on hardware but ridiculously expensive for developers to properly implement. In both cases, this is tech that really needs to be integrated into game engines before it can be widely used. Unreal Engine 4 can take care of the sound problems via templates.