planning

Prompt: make K2 set delay feedback (softcut.pre_level(1,x)) to a random value between 0.2 and 0.99

Questions to consider:

• where in the code does the K2 interaction happen?
• how do we generate random values between two floats and return it to softcut voice 1 via softcut.pre_level(1,x)?

finding K2

In clock by hand, we modified the functionality of K2:

-- key
function key(n,z)
  if n==3 and z==1 then
    -- K3, on key down toggle chimes true/false
    chimes = not chimes
  elseif n==2 and z==1 then -- key 2's interaction!
    --[[ 0_0 ]]--
	sequence = not sequence
  end
end

Let’s comment-out sequence = not sequence and add our modification below!

making random values (less than 1)

In even strum, we discussed how math.random generates different ranges of random values depending on how many arguments are supplied to it.

>> math.random() -- generates random floats between 0 and 1
>> math.random(10) -- generates random integers between 1 and 10
>> math.random(33,56) -- generates random integers between 33 and 56

However, our prompt calls for a random float between 0.2 and 0.99. But if we try to execute math.random(0.2,0.99), we get the following error:

lua: 
stdin:1: bad argument #1 to 'random' (number has no integer representation)
stack traceback:
	[C]: in function 'math.random'
	stdin:1: in main chunk

So, we can’t pass floats to math.random – we need to work with integers. What do you think we should do?

Hint: 0.2 and 0.99 are equivalent to 20/100 and 99/100…

putting it together

-- key
function key(n,z)
  if n==3 and z==1 then
    -- K3, on key down toggle chimes true/false
    chimes = not chimes
  elseif n==2 and z==1 then -- key 2's interaction!
    --[[ 0_0 ]]--
    -- sequence = not sequence
    softcut.pre_level(1, math.random(20,99)/100)
  end
end