SL_I3DL2_ENVIRONMENT_PRESET_PLAIN

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
extern (C)
enum SL_I3DL2_ENVIRONMENT_PRESET_PLAIN = SLEnvironmentalReverbSettings(-1000, -2000, 1490, 500, -2466, 179, -2514, 100, 210, 1000);

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