// license:BSD-3-Clause // copyright-holders:Derrick Renaud, Couriersud #include "emu.h" #include "flt_vol.h" // device type definition DEFINE_DEVICE_TYPE(FILTER_VOLUME, filter_volume_device, "filter_volume", "Volume Filter") //------------------------------------------------- // filter_volume_device - constructor //------------------------------------------------- filter_volume_device::filter_volume_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) : device_t(mconfig, FILTER_VOLUME, tag, owner, clock), device_sound_interface(mconfig, *this), m_stream(nullptr), m_gain(0) { } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void filter_volume_device::device_start() { m_gain = 0x100; m_stream = stream_alloc(1, 1, machine().sample_rate()); } //------------------------------------------------- // sound_stream_update - handle a stream update //------------------------------------------------- void filter_volume_device::sound_stream_update(sound_stream &stream, stream_sample_t **inputs, stream_sample_t **outputs, int samples) { stream_sample_t *src = inputs[0]; stream_sample_t *dst = outputs[0]; while (samples--) *dst++ = (*src++ * m_gain) >> 8; } void filter_volume_device::flt_volume_set_volume(float volume) { m_stream->update(); m_gain = int(volume * 256); }