On my H2O, LeanAndMean seems to affect very few things:
* The black menu highlights when you tap on something. And that's it
.
true:
Code:
[pid 516] 20:31:05 [2f1b21bc] ioctl(3, MXCFB_SEND_UPDATE, {update_region={top=27, left=34, width=77, height=104}, waveform_mode=NTX_WFM_MODE_A2, update_mode=UPDATE_MODE_PARTIAL, update_marker=159, temp=TEMP_USE_AMBIENT, flags=EPDC_FLAG_FORCE_MONOCHROME, alt_buffer_data={virt_addr=(nil), phys_addr=0, width=0, height=0, alt_update_region={top=0, left=0, width=0, height=0}}}) = 0
[pid 516] 20:31:05 [2f1b21bc] ioctl(3, MXCFB_WAIT_FOR_UPDATE_COMPLETE, {159}) = 966
vs.
false:
Code:
[pid 516] 20:33:46 [2f1b21bc] ioctl(3, MXCFB_SEND_UPDATE, {update_region={top=27, left=34, width=77, height=104}, waveform_mode=WAVEFORM_MODE_AUTO, update_mode=UPDATE_MODE_PARTIAL, update_marker=49, temp=TEMP_USE_AMBIENT, flags=0, alt_buffer_data={virt_addr=(nil), phys_addr=0, width=0, height=0, alt_update_region={top=0, left=0, width=0, height=0}}}) = 0
[pid 516] 20:33:46 [2f1b21bc] ioctl(3, MXCFB_WAIT_FOR_UPDATE_COMPLETE, {49}) = 936
(that's on tapping the Home icon)
In plain English, when true, menu highlights are done in the fastest eink refresh mode available, the bitonal one.
I couldn't find anything different, at least in terms of visible data when sniffing the ioctls. Same amount of calls, same amount of WAIT_FOR_UPDATEs.
Fun detail: the black selection around a tile is still done in A2, although without the force_mono flag (in both cases).
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Again, that's on a H2O, with a Carta screen, so, by definition it behaves differently than a Pearl, and nickel/the kernel might do some other magic behind the scenes depending on devices, I've already said this before, but the eink driver in Kobo's kernels is notably murkier than Amazon's on this aspect, so it's hard to pinpoint with hard data
.
It's hard to know what the kernel does behind the scenes to make its choice with the automagic WAVEFORM_MODE_AUTO waveform mode.
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And, FWIW: defaults to true on my H2O
.