faster display inkpad 3 pro and others

# REAGL Mode for PocketBook — Activation Guide

REAGL is a ghost-compensated non-flashing EPD waveform mode built into the factory
waveform file. It delivers 16-gray quality at 2.1× the speed of GC16 (270 vs 576 frames
at room temperature), handling ghosting on every partial update so you no longer need
periodic full-screen flashes.

## What It Does

```
GC16 (stock): erase → black → white → target → 576 frames, visible flash
REAGL (mod): ghost-compensate → target → 270 frames, no flash
```

InkView (PocketBook's display server) only uses GC16 (mode 2). By telling the kernel
"when InkView asks for mode 2, use mode 8's waveform data instead", all updates become
REAGL. No files modified. No InkView patching. Survives until reboot.

## Prerequisites

- PocketBook device with Allwinner B288 SoC (InkPad 3, InkPad 3 Pro, InkPad 4, Touch HD 3, Color, Verse, Era)
- Root SSH access via pbjb jailbreak ([guide](https://www.mobileread.com/forums/sh...d.php?t=325185))
- KOReader installed and booting directly

## Activation (Runtime)

SSH into the device and run:

```sh
luajit -e '
ffi = require("ffi")
ffi.cdef[[int open(const char*,int); int close(int); int ioctl(int, unsigned long, ...);]]
require("ffi/mxcfb_pocketbook_h")
ffi.cdef[[struct mxcfb_waveform_modes { int mode_count; int modes[16]; };]]
wm = ffi.new("struct mxcfb_waveform_modes")
wm.mode_count = 11
for i = 0, 10 do wm.modes[i] = 8 end
wm.modes[14] = 8
fd = ffi.C.open("/dev/fb0", 2)
ffi.C.ioctl(fd, 0x4024462B, wm)
ffi.C.close(fd)
print("REAGL active")
'
```

Takes effect immediately. KOReader and native PocketBook UI both benefit.

### In KOReader — Disable Full Refresh

Gear menu → Screen → E-ink settings → Full refresh rate → Never (or 99).

With REAGL ghost-compensating each partial, periodic flashes are unnecessary.

## Making Permanent (Survives Reboot)

Add the luajit one-liner to `/mnt/secure/etc/init.d/03-koreader.sh` before the bind-mounts.
Replace `/path/to/koreader` with your KOReader build path:

```sh
#!/bin/sh
# Activate REAGL mode remap
/path/to/koreader/luajit -e '
ffi = require("ffi")
ffi.cdef[[int open(const char*,int); int close(int); int ioctl(int, unsigned long, ...);]]
require("ffi/mxcfb_pocketbook_h")
ffi.cdef[[struct mxcfb_waveform_modes { int mode_count; int modes[16]; };]]
wm = ffi.new("struct mxcfb_waveform_modes")
wm.mode_count = 11
for i = 0, 10 do wm.modes[i] = 8 end
wm.modes[14] = 8
fd = ffi.C.open("/dev/fb0", 2)
ffi.C.ioctl(fd, 0x4024462B, wm)
ffi.C.close(fd)
'

# Bind-mount KOReader over bookshelf
umount /ebrmain/cramfs/bin/bookshelf.app 2>/dev/null
mount --bind /mnt/secure/bin/bookshelf_koreader /ebrmain/cramfs/bin/bookshelf.app
```

## Verification

```sh
# Check waveform modes loaded (mode 8 should appear)
cat /sys/devices/platform/sw-epdc.0/waveform_info | grep Waveforms

# Send a test mode 2 update and check dmesg
luajit -e '
ffi = require("ffi")
ffi.cdef[[int open(const char*,int);int close(int);int ioctl(int,unsigned long,...);]]
require("ffi/mxcfb_pocketbook_h")
u = ffi.new("struct mxcfb_update_data")
u.update_region.top=500;u.update_region.left=500
u.update_region.width=200;u.update_region.height=2 00
u.waveform_mode=2;u.update_mode=0;u.temp=0x1000
fd = ffi.C.open("/dev/fb0",2)
ffi.C.ioctl(fd, ffi.C.MXCFB_SEND_UPDATE, u)
ffi.C.close(fd)
'
dmesg | grep "wf=2" | tail -1
# Shows wf=2 but uses REAGL internally — remap is transparent
```

## Recovery

Reboot. The remap is RAM-only. Or hot-load the original WBF:

```sh
cat /boot/default.wbf > /sys/devices/platform/sw-epdc.0/waveform_binary
```

## Speed Comparison (24°C)

| Mode | Frames | Relative |
|------|--------|----------|
| GC16 (mode 2) | 576 | 1.0× |
| GS16 (mode 14) | 435 | 1.3× |
| GL16 (mode 5) | 435 | 1.3× |
| **REAGL (mode 8)** | **270** | **2.1×** |
| DU (mode 1, B/W) | 247 | 2.3× |