diff options
Diffstat (limited to 'applause.lua')
| -rw-r--r-- | applause.lua | 51 |
1 files changed, 50 insertions, 1 deletions
diff --git a/applause.lua b/applause.lua index 1b1701a..b8b7631 100644 --- a/applause.lua +++ b/applause.lua @@ -343,11 +343,18 @@ end function Stream:delay(length) return DelayStream:new(self, length) end +function Stream:delayx(length, max_length) + return DelayXStream:new(self, length, max_length) +end function Stream:echo(length, wetness) local cached = self:cache() return cached:mix(cached:delay(length), wetness) end +function Stream:echox(length, wetness, max_length) + local cached = self:cache() + return cached:mix(cached:delayx(length, max_length), wetness) +end -- This is a linear resampler thanks to the -- semantics of IndexStream @@ -1641,6 +1648,48 @@ function DelayStream:len() end -- +-- Delay line with a variable (stream) length and +-- maximum length. Non-interpolating. +-- This is not part of DelayStream, mainly because +-- we cannot accurately calculate the length of the resulting +-- stream. +-- FIXME: Probably currently broken. +-- +DelayXStream = DeriveClass(MuxableStream) + +DelayXStream.sig_last_stream = 2 + +function DelayXStream:muxableCtor(stream, length, max_length) + self.stream = stream + self.length = length + self.max_length = max_length or sec(1) +end + +function DelayXStream:gtick() + local ceil = math.ceil + local tick = self.stream:gtick() + local length_tick = self.length:gtick() + local max_length = self.max_length + local buffer = table.new(max_length, 0) + local write_pos = 1 + local read_pos = 1 + + for i = 1, max_length do buffer[i] = 0 end + + return function() + local sample = buffer[ceil(read_pos)] + buffer[write_pos] = tick() + write_pos = (write_pos % max_length) + 1 + read_pos = (read_pos + max_length/length_tick()) % max_length + return sample + end +end + +function DelayXStream:len() + return self.max_length + self.stream:len() +end + +-- -- MIDI Support -- NOTE: The MIDIStream is defined at the very end, since -- we need to use primitives not yet defined @@ -1771,7 +1820,7 @@ function Stream:fton() return self:map(fton) end -- Attack-Sustain and Decay phases based on real-time control signals. -- The note values can be passed into the constructor by using functions -- for the "on" and "off" streams. --- Usually, the note stream will be a MIDIVelocityStream, so the two +-- Usually, the note stream will be a MIDIStream:mvelocity(), so the two -- instrument streams can be based on the MIDI velocity (but don't have -- to be if the velocity is not important). InstrumentStream = DeriveClass(MuxableStream) |