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#ifdef DSP_CPP
inline void DSP::voice_output(voice_t& v, bool channel) {
//apply left/right volume
int amp = (state.t_output * (int8)VREG(voll + channel)) >> 7;
//add to output total
state.t_main_out[channel] += amp;
state.t_main_out[channel] = sclamp<16>(state.t_main_out[channel]);
//optionally add to echo total
if(state.t_eon & v.vbit) {
state.t_echo_out[channel] += amp;
state.t_echo_out[channel] = sclamp<16>(state.t_echo_out[channel]);
}
}
void DSP::voice_1(voice_t& v) {
state.t_dir_addr = (state.t_dir << 8) + (state.t_srcn << 2);
state.t_srcn = VREG(srcn);
}
void DSP::voice_2(voice_t& v) {
//read sample pointer (ignored if not needed)
uint16 addr = state.t_dir_addr;
if(!v.kon_delay) addr += 2;
uint8 lo = smp.apuram[(uint16)(addr + 0)];
uint8 hi = smp.apuram[(uint16)(addr + 1)];
state.t_brr_next_addr = ((hi << 8) + lo);
state.t_adsr0 = VREG(adsr0);
//read pitch, spread over two clocks
state.t_pitch = VREG(pitchl);
}
void DSP::voice_3(voice_t& v) {
voice_3a(v);
voice_3b(v);
voice_3c(v);
}
void DSP::voice_3a(voice_t& v) {
state.t_pitch += (VREG(pitchh) & 0x3f) << 8;
}
void DSP::voice_3b(voice_t& v) {
state.t_brr_byte = smp.apuram[(uint16)(v.brr_addr + v.brr_offset)];
state.t_brr_header = smp.apuram[(uint16)(v.brr_addr)];
}
void DSP::voice_3c(voice_t& v) {
//pitch modulation using previous voice's output
if(state.t_pmon & v.vbit) {
state.t_pitch += ((state.t_output >> 5) * state.t_pitch) >> 10;
}
if(v.kon_delay) {
//get ready to start BRR decoding on next sample
if(v.kon_delay == 5) {
v.brr_addr = state.t_brr_next_addr;
v.brr_offset = 1;
v.buf_pos = 0;
state.t_brr_header = 0; //header is ignored on this sample
}
//envelope is never run during KON
v.env = 0;
v.hidden_env = 0;
//disable BRR decoding until last three samples
v.interp_pos = 0;
v.kon_delay--;
if(v.kon_delay & 3) v.interp_pos = 0x4000;
//pitch is never added during KON
state.t_pitch = 0;
}
//gaussian interpolation
int output = gaussian_interpolate(v);
//noise
if(state.t_non & v.vbit) {
output = (int16)(state.noise << 1);
}
//apply envelope
state.t_output = ((output * v.env) >> 11) & ~1;
v.t_envx_out = v.env >> 4;
//immediate silence due to end of sample or soft reset
if(REG(flg) & 0x80 || (state.t_brr_header & 3) == 1) {
v.env_mode = env_release;
v.env = 0;
}
if(state.every_other_sample) {
//KOFF
if(state.t_koff & v.vbit) {
v.env_mode = env_release;
}
//KON
if(state.kon & v.vbit) {
v.kon_delay = 5;
v.env_mode = env_attack;
}
}
//run envelope for next sample
if(!v.kon_delay) envelope_run(v);
}
void DSP::voice_4(voice_t& v) {
//decode BRR
state.t_looped = 0;
if(v.interp_pos >= 0x4000) {
brr_decode(v);
v.brr_offset += 2;
if(v.brr_offset >= 9) {
//start decoding next BRR block
v.brr_addr = (uint16)(v.brr_addr + 9);
if(state.t_brr_header & 1) {
v.brr_addr = state.t_brr_next_addr;
state.t_looped = v.vbit;
}
v.brr_offset = 1;
}
}
//apply pitch
v.interp_pos = (v.interp_pos & 0x3fff) + state.t_pitch;
//keep from getting too far ahead (when using pitch modulation)
if(v.interp_pos > 0x7fff) v.interp_pos = 0x7fff;
//output left
voice_output(v, 0);
}
void DSP::voice_5(voice_t& v) {
//output right
voice_output(v, 1);
//ENDX, OUTX and ENVX won't update if you wrote to them 1-2 clocks earlier
state.endx_buf = REG(endx) | state.t_looped;
//clear bit in ENDX if KON just began
if(v.kon_delay == 5) state.endx_buf &= ~v.vbit;
}
void DSP::voice_6(voice_t& v) {
state.outx_buf = state.t_output >> 8;
}
void DSP::voice_7(voice_t& v) {
//update ENDX
REG(endx) = (uint8)state.endx_buf;
state.envx_buf = v.t_envx_out;
}
void DSP::voice_8(voice_t& v) {
//update OUTX
VREG(outx) = (uint8)state.outx_buf;
}
void DSP::voice_9(voice_t& v) {
//update ENVX
VREG(envx) = (uint8)state.envx_buf;
}
#endif
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