Is it possible to run a LUA script when inputting values by keyboard?

[dervur]

Hello there,

I am trying to make a modulator for an FM synth, this means ratios with decimal values. I created a Fixed sliders from the actual shown value. That is fine. What I'm wondering is, is it possible to have a lua script run once you click on the number that can process whatever the user has written?
I ask this because if I type with keyboard the value "0.6" I want the slider to go to the equivalent position of what will show as 0.6 (that is modulator value 20 in my case), instead of having it round up to modulator value 1 (as Ctrlr usually does with decimal value).
Writing the script will be fine. I am just wondering if it is possible what I would like to do.

I see there are plenty of function when mouse is up or down, but this does not (I think) work in my scenario.

Or is there an alternative for me to obtain fractional modulator values?

Cheers

For reference this is how I populated the fixed slider values:

        -- Define the start value, end value, and step
        local start_value = 0.500
        local end_value = 1
        local step = 0.005

        -- Fill the table with values from 0.500 to 0.995
        for value = start_value, end_value, step do
            table.insert(values, string.format("%.3f", value))
        end

        -- Define the new start value, end value, and step
        local start_value = 1
        local end_value = 32
        local step = 0.01

        -- Fill the table with values from 1 to 31.99
        for value = start_value, end_value, step do
            table.insert(values, string.format("%.2f", value))
        end

    -- Concatenate the strings of values with newline characters
    local concatenatedStrings = table.concat(values, "\n")

    panel:getModulatorByName(fader):getComponent():setProperty("uiFixedSliderContent", concatenatedStrings, false)

[damiensellier]

if the scale is linear you can probably use an uiSlider instead of the fixed one, but with an expression for calculating in/out value.

you would also need to set the min max value with a custom increment.

[dervur]

Yeah I was trying to set up float intervals, but it seems only integers are accepted (If I put for example 0.005, it puts an interval of 1).

It is not a problem what the actual value is (I will have to break it down anyway as it will be two sysex messages, coarse value and fine value)), I would just like to have something where you can write the decimal value and it then goes to the nearest one available. But for now only integers seems to be a possibility at the input from keyboard...

[dervur]

What is also very weird is that, if I click on the value to change and it is for example 0.650, the textbox will show as 0.650 from the keyboard input, if you press enter the value dIoes not change, but if you try to write "0.650" in the box, it will round up to the value for 1 (and then show its equivalent in the fixed value)
How it shows when I click on the value:

If I do not modify it and press enter, it stays at 0.700:

Now, let's say I delete a 0 from the end:

What will show up is the equivalent value when the modulator is equal to 1 instead:

Even if you write "0.700", the value shown will be 0.505...

[damiensellier]

Yes I tried and it gave me the same thing.
I usually go for uifixed slider with the interval between values I am looking for.
I'll post below a link to a page where you can generate lists of values with the interval you need.

I'll check that interval parameter for sliders. Now it's just set to 1 whatever value you set it has no effect. I already opened an issue on ctrlrx.

I'll post later with the link to do your uifixedslider value list.

[damiensellier]

https://pinetools.com/generate-list-numbers

here is the tool to generate custom lists for your uiFixedSlider

In your case 1 to 32 with step 0.001 and you need "\n" as suffix for the line break if you set it from a lua script as property.
Copy paste this in your value list and you already have the right values :)

EDIT: below

[damiensellier]

Oops I set the interval wrong , you need 0.001 steps :
PineTools.com_2025-02-16_01h15m58s.txt

Just copy paste the content in your "slider content" field :

[dervur]

Oh I didn't know it didn't have any effect (I mean I kinda realized but was not sure).

And yeah that is why I'm using fixed slider for, also cause I have two different step sizes for values <0. I was just wondering for the actual typing in values.

Thanks for the website but I was already using table.concat() in the code to do that, also because based on a button the values will change (ratio or fixed frequency).

Anyway I guess for now it just won't be possible to type in values to change the slider value and that is it, thank you very much for the quick replies!

[damiensellier]

JUCE has a threshold parameter to change increment steps it's called velocity mode, it's in ctrlr but same thing I don't know if it works. I'm currently checking this interval problem and it's been left as work in process in the code :) I will try to implement it for the next version because it's very useful and we all have to generate lists for uiFixedSlider as a workaround.

velocity mode :

https://docs.juce.com/master/classSlider.html#a47c37989ff5f6453f2c44f1a7455e1c1

[damiensellier]

<and no you can't type decimal values because it's always rounded above because of the forced interval of 1.
I noticed a bug as , when you set up min 0 max 1 the slider always stick back to 1... It's really buggy.

[dervur]

Yeah it seems like it. I'll just leave it as it is for now. Maybe divide the value by 100 in the "Expression to evaluate ..." so I can get the right values for ratios <1, and then write the code accordingly.
Or alternatively do you know if in those "expression to evaluate" thing at the top we can also include if statments somehow? I was just trying it but I received an error, maybe I was setting it up wrong this is what I wrote in it: if (modulatorvalue<1) then (modulatorvalue/100)*0.005+0.500 else modulatorvalue/100 end
At least for ratios I would get the right value. For fixed frequency I need to use a look up table in LUA anyway...

[damiensellier]

I spent a little bit of time to analyze how uiSlider works and it's pretty complicated. It's not just a few parameters and good to go. Actually there's some 2 ways logic via the slider operator to update the GUI of the slider from host and midi in messages and at different steps values are only integers which leads to rounding whatever decimals you'll put from the GUI.

Roman Kubiak did it right but forgot to implement the interval parameter in the picture. I'll try to add it to have it work properly but I need to dig deeper into that. The values have to be managed as double type but snapped to integers etc that's complicated.

Mapped values when min is negative gave also wrong steps...

So it needs improvement.

[damiensellier]

I remember now why I used 99% of uiFixedSliders on my panels with huge lists of values to cover decimals.

For the moment this is why I would recommend.

[damiensellier]

I don't think you can put statements in the expression box. you would need to do it via a LUA script.

here is the note from the source code for expressions :

When evaluating expression in either direction a couple of utility functions can be used, the notation is the same as in C
			for example to get the absolute value of the modulator you'd type: "abs(modulatorValue)" as the expression

			A list of constants that can be used:
			- ceil : Returns the smallest integral value of the parameter
			- abs : Returns the absolute value of the parameter
			- floor : Returns the largest integral value that is not greater than the parameter
			- mod : divides two numbers and returns the result of the MODULO operation "%" in C 10 % 3 = 1, 0 % 5 = 0; 30 % 6 = 0; 32 % 5 = 2
			- fmod : Returns the floating-point remainder of the two parameters passed in
			- pow : Returns the first parameter raised to the power of the second (dunno what that could be used for but it's there)
			- gte : Return the larger or equal of the two passed parameters (a >= b), gte (modulatorValue, 0, modulatorValue, 128 - modulatorValue)
					will return modulatorValue if modulatorValue is greater then 0 and (128 - modulatorValue) if it is less then zero
			- gt : same as gte but greater then without the equal sign (a > b)
			- max : returns the bigger of two parameters
			- min : returns the smaller of two parameters
			- getBitRangeAsInt (value, startBit, numBits)
			- setBitRangeAsInt (value, startBit, numBits, valueToSet)
			- clearBit (value, bitToClear)
			- isBitSet (value, bitPosition)
			- setBit (value, bitToSet)
			- setGlobal (globalIndex, newValueToSet)

[damiensellier]

Let's say for a slider with min 0.0 max 1.0 interval 0.1 that would send message with modulatorValue*10 (valid integer) I can't get it to send 0,1,2,3 etc it only sends 0,0,0...,10

there's a double to integer conversion at one point that rounds up the value and won't allow to do it.

[dervur]

Do you think it would be easier to implement something instead that cross check the input of the keyboard (given it is numerical) with the fixed values (the closest one if they are numeric)? Maybe even as a box to tick and not always on

In this way fixed values can be used for the actual decimal representation, but if somebody writes 1.7 the code would not round it up to 2 and set whatever it is the third value in the fixed value list but instead set whatever value is closer to 1.7 or actual 1.7 if available.

or maybe that would be an even bigger headache...

[damiensellier]

There's several way to snap to modulator values, I'm not sure I really understood 100% your need but with fixedSliders your input message value should give back the index value of your "slider content".

You can also use lua scripts to filter incoming values and return a mapped value from a table (according to index number)

[dervur]

Hi Damien, I know that, and that is what I do not want for decimal values. Instead of the index I would like the modulator to go at the equivalent values from list of fixed values.

Let's say the fixed modulator has three values: 0.5, 0.6 and 0.7
Then, I click on the number (this allows me to type the value from keyboard), if I type 0.7 from the keyboard I want the modulator to go to index 2 (what in the fixed modulator value shows as 0.7).
Right now, it would round up the value and go to index 1 instead (regardless of the decimal part), going then to 0.6.

I don't even know if such a thing is possible from the source code, but if it is it would make sense to have an added modulator property as a tick button that allows such a thing (or not).
I think this is the biggest issue compared to having intervals with a decimal part on conventional operator, because the actual visualization and intervals can be solved using a fixed value modulator, but they don't allow us to type in the value we would like to see instead.

If I still wasn't clear let me know and I can make a video about it.

[damiensellier]

totally get it.
I am analysing how the sliders are actually working and especially the processor side to have the mod reacts from the GUI, MIDI IN or Host all together.

uiFixedSlider is already using the snapping feature from the JUCE slider class. In fact, there's no such thing as fixed slider in JUCE. it's snap to values from an array of values property (valuemap).

What you are actually refering to is the part getValueFromText() that needs to be overriden and improved.

Also I think all the slider part of ctrlr has rounding problem because slider setRange() is using double float values as well as int, those are that are more precise than float. However all the host<>ctrlr part and comparison is done with float so decimal values from float to double are not exactly thesame for exemple 5.7 is actually 5.676954 something like that.

I'll check that later :
https://docs.juce.com/master/classSlider.html#a532774d3294a058784f7d4291b33b720

I'll check this snap to value from text problem on uiFixedSlider when I'll understand 100% the whole logic behind it.
But yeah all that float, int, double conversion with normalise/denormaliseValue() is a huge headache.

[dnaldoog]

This was difficult. I created a copy of the table that this function accesses, which is a reverse of your table values substituting the key for value like php array_flip() calling the table reverse, but I needed another copy of it called proxy for the metamethod to be able to loop through looking for the closest match in table reverse. Seems to be the case that .__index cannot loop through the table parameter usually t as in __index=function (t,k) …. Not 100% sure there.

I think this must be inefficient (creating three tables of the same data).

Would be interesting to find a more elegant solution, but it works as far as I can tell and it is quite a useful feature. I can see why you wanted to implement this.

---

init (constructor)

init = function(--[[ CtrlrInstance --]] type)
    values = {}
    -- Define the start value, end value, and step
    local start_value = 0.500
    local end_value = 1
    local step = 0.005

    -- Fill the table with values from 0.500 to 0.995
    for value = start_value, end_value, step do
        table.insert(values, string.format("%.3f", value))
    end

    --Define the new start value, end value, and step
    local start_value = 1
    local end_value = 32
    local step = 0.01

    -- Fill the table with values from 1 to 31.99
    for value = start_value, end_value, step do
        table.insert(values, string.format("%.2f", value))
    end

    -- Concatenate the strings of values with newline characters
    local concatenatedStrings = table.concat(values, "\n")

    panel:getComponent("fader"):setProperty("uiFixedSliderContent", concatenatedStrings, false)

    for i, v in ipairs(values) do
        reverse[v] = i - 1
    end

    proxy = {}

    for k, v in pairs(reverse) do
        proxy[k] = v
    end


end

---

Find nearest value in table and update modulator

meta = {}
meta.__index = function(t, k)
    k = tonumber(k)
    local rec, value = 0, 0
    local r = proxy
    for key, v in pairs(r) do
        if math.abs(k - key) < math.abs(k - rec) then
            rec = key
            value = v
        end
    end
    t[k] = value
    return t[k]
end

meta.__call = function(t, k)
    return t[k]
end

reverse = setmetatable({}, meta)

---

uiLabel callback

updateFader = function(--[[ CtrlrLabel --]] label --[[ String --]], newContent)
    if panel:getBootstrapState() then
        return
    end
    if USERENTRY then
        if type(tonumber(newContent)) ~= "number" then
            utils.warnWindow("Illegal Input", "Please enter valid number")
          return
        end
        local x = reverse(newContent)
        panel:getModulatorByName("fader"):setModulatorValue(x, false, true, false)
        USERENTRY = false
    end
end

yamaha slider devur_1_0.zip

[dervur]

This is actually amazing! It is not super perfect due to current CtrlrX limitations, but probably with some further lua coding one can solve this for now.
I will try later to hide the value box of the modulator and use the uiLabel "user input" for it, update its values with lua code, then maybe have editing on double click instead of single click for Linear Bar style modulators. And the rest of the code as you did. The only thing I'm scared might happen with this solution is that linear bars might not work properly, or the double click will not work on uiLabel because they will be one on top of the other...
I'll see how it works later this week. But thank you for giving me this idea, I'll report on this thing once I try it out. But for all the other modulators it should be a feasible thing to do as you don't have the number text box where you would usually slide up or down.

But maybe in a future version if there is in modulators something like "uiLabelChangedCbk" for the value box of modulators, all of this can be done in one LUA function. @damiensellier in this way you wouldn't need to implement what I was saying at the source, but it is possible for users to implement it in LUA. This depends on if something like uiLabelChangedCbk would make sense for modulators.

[dnaldoog]

Great to hear!

Yes I am still on 5.3.201 - can't teach an old dog new tricks.

I was originally going to have the uiLabel update from the uiSlider. I stopped there because after many fails I finally got it working, but that is what the variable USERENTRY was intended for.

I'll see if I can do it with version 2.0 - Should be doable.

[dnaldoog]

Here is version 2.0 which writes the uiSlider value to the uiLabel.

yamaha slider devur_2_0.zip

[dervur]

This is amazing thank you very much.

I did try right now and my suspects were right, it does not work for linearBar and linearBarVertical style modulator because they overlap. So in my case I cannot use it unfortunately (unless I change my mind on how I show the modulator in my project).

But I'm marking this as the answer because it is a smart solution for all other scenarios of modulators. At least until a future version of CtrlrX that might solve the issue.

[damiensellier]

That's brillant!

[dnaldoog]

Can you show me visually what you are trying to achieve?

It sounds like you want the value to be in the middle of the uiSlider and then the user clicks on the value to edit manually or optionally mouse move to adjust the slider and then the value updates automatically. Is that correct?

If there’s a problem with overlap, there is a solution. But it would involve uiComponent. With an AlertWindow for editing in values.

[damiensellier]

@dervur can you please precise exactly what callback you would need to be implemented?

uiSliderTextValueCbk() ? when you update the value from the text-entry box you want to trigger a LUA script? And what variable you would need to pass to the script?

[damiensellier]

@dervur Also there's a lot of function bind to LUA in CtrlrValueMap.cpp

you should be able to get the corresponding text value from the index (line) in the uiFixedSliderContent box

int CtrlrValueMap::getMappedValue(const int valueIndex) const
{
	return (values[valueIndex].numericValue);
}

		int getMappedValue(const int valueIndex) const;

		/** @brief Get the index of a value based on the value's text

			@param	textRepresentation	the text to look for
			@return	the index of the value with this text
		*/

LUA

	.def("getMappedValue", (int (CtrlrValueMap::*)(const String &) const) &CtrlrValueMap::getMappedValue)
        .def("getMappedValue", (int (CtrlrValueMap::*)(const int) const) &CtrlrValueMap::getMappedValue)

[dervur]

I have misunderstood what uiSliderTextValueCbk() did, I don't think it is feasible now that I looked more into it... Unless it is possible to send to the callback what the user has input before it actually reaches the core code that sets the fixed value.
Basically, if the user writes "0.700" this should pass through the lua code before reaching the actual core code that process it and rounds it up to "1", but I don't think it is possible. I might be wrong though.

[damiensellier]

I opened an issue on ctrlrx, tell me if I'm in the scope of work ;)

damiensellier#72

[damiensellier]

damiensellier#72

[dnaldoog]

Here is solution using uiComponent. Values can be changed manually by double click or by scroll wheel and/or mouse drag.

The modulator fader is now in a hidden layer and this modulator would receive MIDI in and automatically update the uiComponent visible to user. Of course adjusting the uiComponent changes fader thus sending out MIDI. You could do all this without the hidden modulator, but it works well.

yamaha slider devur_3_0.zip