Zynthian UI parameter editing resolution drop in oram

[polluxsynth]

Describe the bug In the old 32-bit image, the resolution of parameters when editing using the Zynthian UI seemed to be about 1/200th of the parameter range. By resolution, I mean how much the parameter changes when the encoder is moved one click. So, for instance, a parameter whose range is 0..10 would have increments of 0.05 . Parameters with a range of 0..1 would have increments of 0.005 . This offers excellent control of parameters.

With oram, this seems to have changed, in a somewhat haphazard way. To take one example, all OB-Xd parameters have a range of 0..1, and the resolution is now 0.01 . This means that there are 100 steps for the whole range, which is borderline acceptable compared to the way it was before. Classically hardware synths have ranges of 0..63, 0..100 or 0..127, so it's in the same ballpark at least, but it's step back from the previous version.

However, in some cases, such as the MiMi-d, the resolution seems not to be based on the parameter itself but ... something else (maximum range of parameters on the same page? No idea. I just note that the resolution seems to be different compared OB-Xd for similarly ranged parameters). For instance, the oscillator detune range of the MiMi-d is -1..+1 (semitones). In the old 32-bit stable image, the resolution was around 0.01 or so, but with oram, it is 0.1, yielding a mere 20 values (10 cent increments) within the range, which makes editing this parameter in the Zynthian UI useless.

To Reproduce

1. Create a chain with MiMi-d
2. Go to an oscillator page
3. Adjust the oscillator detune parameter
4. Note how the resolution is 0.1, so the whole range is a mere 20 steps

Expected behavior The resolution should not be worse than it was with the old 32 bit stable image.

Setup:

• SD-image: 2024-09-23-zynthianos-bookworm-aarch64-oram-2409.img (plus updates)

• Hardware Config (Zynthian v4 - in the webconf, Kit is set to v4): Raspberry Pi 4 Model B Rev 1.4 Audio: HifiBerry DAC+ ADC PRO Display: ZynScreen 3.5 (v1) Wiring: MCP23017_ZynScreen I2C: MCP23017@0x20, MCP23017@0x21, ADS1115@0x48, MCP4728@0x61

• Software Version zyncoder: oram (71de6d2) zynthian-ui: oram (bbc7246) zynthian-sys: oram (a717e49) zynthian-data: oram (ddfa009) zynthian-webconf: oram (b530397)

[riban-bw]

There is a new coarse/fine control. With encoders, you press and turn for fine control. With touchscreen you swipel left/right for fine control. I haven't yet looked to see how you might do the fine control with bound control like CUIA binding. @jofemodo, did you consider this when adding this feature?