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[[start|Welcome]]/[[Apps|Apps]]/[[VividShaper| VividShaper]]/VividShaper reference manual
====== VividShaper Reference Manual ======

VividShaper is a wavetable AUv3 plugin synthesizer, where each wave consists of 128 samples. Instead of having a fixed number of waves to choose from, VividShaper allows you to program your own waves using the built in Lua programming language and change them over time.

The Lua-code is called many times per second. This allows the waves to be programmatically changed in realtime. Default is 93.75 times/second, meaning it is updating after 512 frames at 48000 Hz sample rate. This can be changed as well (128 = 375 times/sec, 256, 512, 1024, 2048, and 4096 ≈ 12 times/sec). 

There are up to eight generators for polyphony (the number of generators can be set from 1 to 8). Each generator has in turn up to eight oscillators. Each oscillator has the following states that can be manipulated in Lua-code:

   * volume
   * volume at gate onset
   * left-right panning
   * note (including cent note)
   * pitch bend information
   * A wave table array containing 128 samples

The generator will use the volume information for each oscillator to change the output volume for each wave. Hence, you don't have to adjust the volume in the wave table.

Having a high update frequency and many generators is demanding on the CPU. Many times, a lower update frequency will give the same sound, but will require less CPU power. Also, it may not always be necessary with eight generators.

The first row is always a comment describing the name of the patch (-- Patch: <name>). This name will be relapsed if the patch is saved in a different name. VividShaper will add it for you when saving the patch if you forget to add it yourself.

===== A simple example =====
In this example, we'll demonstrate how to create a basic patch using VividShaper's Lua API.

<code Lua>
-- Patch: A simple example #simple
wave[1] = VSTriangle(1,0)
vol[1] = VSADSRE(1,1,0.8,3,0,gatetimeon,gatetimeoff)
active = vol[1] > 0.00001
pitchbend = pitchbend*2
</code>

This example shows the process of generating a wave and setting its volume envelope in VividShaper. The line **wave[1] = VSTriangle(1,0)** creates a triangle wave at the base frequency of 1 Hz and phase of 0 degrees (between 0-360 degrees). You need to provide both arguments even if you are not phase shifting the wave. The frequency here refers to the number of complete cycles of the Triangle wave form that fits within the sample (consisting of 128 sample points). A frequency of 1 Hz means one complete cycle of the triangle fits within the 128 samples.

This is not the playback frequency of the note (i.e. which note that is being played). The speed of the 128 samples is determined by note[1] for oscillator 1. We don't have to set note[1] explicitly, it is already set by the note you are playing on the keyboard. However, if we do wish to change it, for instance transposing one octave, we can do so by setting: **note[1] = notein+12**. Alternatively, if we wish to set it to a constant value, making it play back the same note even if play another note, we could do that as well: **note[1] = 40**.

The pitch bend value comes from your keyboard and will be added to the note value for each oscillator after the Lua code has finished. This value is stored in the variable pitchbend, which goes from -2 to +2 (i.e. 2 semi-notes). If note[1] == 40 for oscillator 1 and pitchbend == 0.53, the final note value used to play the note will be 43.53. If you want to turn off pitch bend, you can set pitchbend = 0 anywhere in your code. if you want to pitch bend from -4 to +4, you can just multiply it by 2 (pitchbend = pitchbend *2). This is done in the example above. You can also use the pitch bend value to modulate e.g. something else first, then set it to zero if you don't want it to also bend the notes.

The volume will then be set to an exponential volume ADSR envelope, with attack=1 sec, decay=1 sec, sustain=0.8, release=3 sec, startlevel=0. The name of the wave table will be "A simple example".

The last row checks if the volume is above a certain threshold. If not, the boolean variable **active** will be false and the generator will turn off. It is not needed but you save some CPU power by turning off non-sounding generators.

The patch name **A simple example #simple** has a hashtag **#simple**. Adding hashtags to your patch names will allow you to organise your patches into categories (e.g. #bass, #pad, #lead, or whatever you want).

This is all it takes to generate a simple wave. This will then be played back at different speeds, depending on the note being played.

===== API =====

List of built in VividShaper variables:
<code Lua>
-- Input information
notein         -- The current input note for the active generator.
pitchbend      -- The pitch bend data, from -2 to 2.
tempo          -- Current tempo (beats per second, e.g. 120).
timesignnum    -- Time signature numerator, e.g. 3 for three beats per bar (3/4). (Next version)
timesignden    -- Time signature denominator, e.g. 4 for 3/4 time signature. (Next version)
prevbeatpos    -- Previous beat position. (Next version)
beatpos        -- Current beat position.
velocity       -- The MIDI velocity of the note (normalised between 0 to 1).
gate           -- Either 1 or 0 depending on if gate is on or off.
gatetimeon     -- Time in seconds for how long the key was pressed.
gatetimeoff    -- Time in seconds since the key was released.
timeon         -- The number of seconds since the generator was turned on. Resets after parse.
gtimeon        -- Global time. The number of seconds since the first generator was turned on. Resets after parse.
tick           -- The number of times the Lua code has been called since initiation (when tick=0).
cc[x]          -- Value of CC message x (between 0 to 127).
ncc[x]         -- Normalised value of CC message x (between 0 to 1).
par[x]         -- Parameter x. (Next version)
prevvol[x]     -- The volumes for each oscillator when the gate flipped from off to on.
midi[x]        -- MIDI message input array. One array of three elements for each midi message. (Next version)
playing        -- A value true/false. True value means the sequencer is running, false means it has stopped.

-- Output information
pitchbend      -- The pitchbend is sent back as output information. Set it to zero if you don't want it to pitch bend the notes.
wave[x]        -- Wave array x (one array for each oscillator x, 128 elements).
panning[x]     -- Panning for oscillator x (between 0 - 1; 0 = left, 0.5 = middle, 1= right).
note[x]        -- Note output for oscillator x (default value is the same as note).
vol[x]         -- Volume for oscillator x. Default is 0.
ring[x]=y      -- Oscillator x should be ring moduled by oscillator y, where x>y.
sync[x]=y      -- Oscillator x should be synced by oscillator y, where x>y.
gvol           -- Global volume, default = 1. Multiplied on the output to amplify or limit the audio.
updatefreq     -- Update frequency: 128, 256, 512, 1024, 2048, or 4096. Tells how many frames to wait before running Lua.
generators     -- Number of generators (between 1 to 8).
active         -- A value true/false. A false value turns off the generator until it is turned on again.
midigenerator  -- A value true/false. A true value means only one generator will be running and it cannot turn off.

-- Coming soon in a future version (v1.4 probably)
sample[x]      -- Set oscillator x to a specific sample, e.g. sample[1] = "alien"
loopstart[x]   -- Set loop start point as value between 0 - 1
loopend[x]     -- Set loop end point as value between 0 - 1
sxfade[x]      -- Sample cross fade
svol[x]        -- Volume output for sample playback

-- Delay output information
delay1[x]      -- Delay1 parameters:
               --   delay1[1] = own feedback (value from 0 - 1)
               --   delay1[2] = feedback from delay2 
               --   delay1[3] = wet (0 - 1, 0 = dry sound, no delay, 1 = only delay)
               --   delay1[4] = Amplify value before sending to main output (default value 1)
               --   delay1[5] = panning (0 = left, 1 = right)
               --   delay1[6] = time in seconds, e.g 0.5 for half a second delay     
delay2[x]      -- Delay2 parameters
d1vol[x]       -- How much of the output from oscillator x that should be routed to delay1 bus
d2vol[x]       -- How much of the output from oscillator x that should be routed to delay2 bus
ovol[x]        -- How much of oscillator x that should be sent to main output (1 = default)
mvol           -- Amplify main output only (1 = default)

-- Views settings
text           -- A text string that is printed in the waves view.
scaleview      -- The waves view is normally between [-1, 1]. Setting scaleview=0.5 changes to [-0.5, 0.5].
wavesview      -- Which wave to show, between [1, 8]. Set it to 0 for oscilloscope view (default).
oscnote        -- For the oscilloscope view, set the frequency to follow (note number). Default is notein.
</code>

List of built in VividShaper functions:
<code Lua>
-- Wave generators
wave[x] = VSSin(frequency,phase)           -- Sine-wave. frequency=1 is base, phase is in degrees.
wave[x] = VSTriangle(frequency,phase)      -- Triangle-wave.
wave[x] = VSSaw(frequency,phase)           -- Sawtooth-wave.
wave[x] = VSSquare(frequency,phase,width)  -- Square-wave. Width is between 0 to 1.
wave[x] = VSNoise(seed)                    -- Random generated wave, given the seed integer.

-- A neural network autoencoder has been trained with over 4000 different wavetables to be able to
-- reconstruct waves from a two dimensional "latent space". 
latentspace = {0.5, -0.2}                  -- latentspace is an array of two elements in the range [-1, 1]
wave[x] = VSAutodecoder2(latentspace)      -- Creates a new wave given the 2D coordinate in latent space
latent  = VSAutoencoder2(wave)             -- Obtain latent space coordinate for the given wave

-- Wave manipulators
wave[x] = VSWaveFold(wave[x],amplify)         -- Wave will be folded outside the range [-1, 1].
wave[x] = VSNorm(wave[x],threshold,normvalue) -- Normalise the waveform to normval if max amplitude is above threshold
wave[x] = VSAbs(wave[x])                      -- Return absolute values of the input wave.

-- Wave math operators - arguments can be either arrays or scalar factors
wave[x] = VSMul(wave1,wave2) -- Multiply element-wise wave1 with wave2
wave[x] = VSMul(wave1,1.5)   -- Multiply element-wise wave1 with 1.5
wave[x] = VSDiv(1,5,wave2)   -- Divide element wise 1.5 with wave2
wave[x] = VSAdd(wave1,wave2) -- Add element wise wave1 with wave2
wave[x] = VSSub(wave1,wave2) -- Subtract element wise wave1 with wave2

-- LFOs (Low Frequency Operators):
-- These LFO functions take time as input. They are similar to the wave generators in how they
-- operate, but they only return a scalar value between [-1, 1]. (v1.2):
lfo = VSLFOSin(frequency,phase,time)          -- phase is in degrees
lfo = VSLFOTriangle(frequency,phase,time) 
lfo = VSLFOSaw(frequency,phase,time)
lfo = VSLFOSquare(frequency,phase,width,time) -- width is between 0 to 1

-- Helper functions to remove negative values (Rect = rectify)
output = VSRect(input)  -- Input is a scalar value
wave[x] = VSRect(wave[x]) -- Input is a wave array

-- Helper functions for delays
VSPingPong(feedback,time)     -- This function sets the delay variables needed for ping pong delay.
VSStereoDelay(feedback,time)  -- This function sets the delay variables needed for a stereo delay.
VSMonoDelay(feedback,time)    -- This function sets the delay variables needed for a mono delay.



-- Envelopes
-- The level is the initial volume. Normally, it would start at zero, but could also be initiated to
-- start higher.
vol[x] = VSADSR(attack,decay,sustain,release,initlevel,timeOn,timeOff) -- initlevel is initial volume
vol[x] = VSADSRE(attack,decay,sustain,release,initlevel,timeOn,timeOff) -- Exponential release


-- Filters (x = oscillator)
-- A quad filter consists of 5 coefficents: b0, b1, b2, a1, a2. The 'biquadcoeff' is an array
-- consisting of these 5 coefficients. The functions VSLowpass, VSBandpass, and VSHighpass will
-- set the coefficients given the values. When setting these filter coefficients, both the cutoff
-- frequency and the note value are considered. This is because the cutoff frequency is typically
-- specified relative to the note's frequency.

biquadcoeff = VSLowpass(cutoffFreq,resonance,notein)  -- Helper function to set the quadfilter values
biquadcoeff = VSBandpass(cutoffFreq,resonance,notein) -- Helper function to set the quadfilter values
biquadcoeff = VSHighpass(cutoffFreq,resonance,notein) -- Helper function to set the quadfilter values
wave[x] = VSBiquad(wave[x],biquadcoeff)               -- Apply filter on wave using quadfilter settings

-- MIDI output
-- VSTick is a help function to determine if the beat position crosses a certain time interval.
-- For instance, if length=1/4 (corresponding to a quarter note), VSTick will return true every time
-- the beat position (beatpos) crosses over to a new beat. If length=1, it will return true every time
-- beatpos crosses over to a new bar.

VSMIDI(command,data1,data2) -- Send MIDI data. (v1.2)
VSMIDINote(channel,note,velocity,length) -- Play a given note on the given channel. length=1/4 means a quarter note, (v1.2). channel = 0 to 15, velocity = 0 to 127.
VSTick(prevbeatpos,beatpos,length) -- Returns true for every new time interval with the given length. (v1.2)
</code>
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