From a6e7a81de949883adf4f654ad773a80eb0931d00 Mon Sep 17 00:00:00 2001 From: scribblemaniac Date: Fri, 20 May 2022 11:17:37 -0600 Subject: [PATCH] Use cubic mapping for volume control (#6020) * Use cubic mapping for volume control * Update comment for hardware volume slider --- src/audio_core/dsp_interface.cpp | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/src/audio_core/dsp_interface.cpp b/src/audio_core/dsp_interface.cpp index 1bb2a1d34b..00c8dd65d8 100644 --- a/src/audio_core/dsp_interface.cpp +++ b/src/audio_core/dsp_interface.cpp @@ -84,11 +84,11 @@ void DspInterface::OutputCallback(s16* buffer, std::size_t num_frames) { std::memcpy(buffer + 2 * i, &last_frame[0], 2 * sizeof(s16)); } - // Implementation of the hardware volume slider with a dynamic range of 60 dB + // Implementation of the hardware volume slider + // A cubic curve is used to approximate a linear change in human-perceived loudness const float linear_volume = std::clamp(Settings::values.volume, 0.0f, 1.0f); if (linear_volume != 1.0) { - const float volume_scale_factor = - linear_volume == 0 ? 0 : std::exp(6.90775f * linear_volume) * 0.001f; + const float volume_scale_factor = linear_volume * linear_volume * linear_volume; for (std::size_t i = 0; i < num_frames; i++) { buffer[i * 2 + 0] = static_cast(buffer[i * 2 + 0] * volume_scale_factor); buffer[i * 2 + 1] = static_cast(buffer[i * 2 + 1] * volume_scale_factor);