[BRLTTY] My experience with Humanware Monarch

[Aura Kelloniemi]

Hello list,

Humanware/APH Monarch braille display has been mentioned a few times on this
list lately. I had a chance to try it out just a few days ago and I think it
would be worthwhile to report my experiences here.

So the device is intended to display both text and graphics using braille
dots. It is not separated to distinct lines. Its resolution is 96x40 braille
dots. In computer braille mode it can show 8 lines and 32 columns of text
(assuming empty dot between character cells—both vertically and horizontally).

There are two very important downsides in this device if one plans to use it
as a braille display for accessing text terminals. First of all, the display
renders itself very slowly. Every refresh takes about two seconds (or more).
This includes adding or removing single characters. I did not try it in a
terminal (of course, because there is no driver available), but I suspect that
a two seconds delay is a major issue when trying to navigate a terminal
screen.

The second problem is that the dots that are being rendered must not be
touched during refresh, or the rendering process will be just partial. If the
display is being touched during rendering, the dots being touched may not be
raised/lowered and the user needs to trigger a refresh (there is a
button for that in the display).

Rendering the dots makes considerably more noise than what is usual to braille
displays. Also the dot panel is under a plastic membrane which feels a bit
sticky, especially if one's hands are not very dry. The touch recognition
feature in Monarch works very differently from how it is implemented in some
HandyTech displays. I was told there are some light sensors which detect the
position of the user's finger on the display, and routing/button activation
needs to be triggered b pressing a button with the other hand. Lighting
conditions can affect how touch recognition works. For me it worked about 90%
of cases.

I suppose all the "defects" related to display refreshing are due to the
technology used in the display. I don't know how the display works internally,
but certainly the braille dots are controlled in a different way compared to
traditional displays.

What is good in this display? First of all, it is big. Reading long passages
of text with a multi-line display is (for me at least) much faster than with a
single-line display. Also the graphics feature is very nice, although the
resolution is low—but hey, now blind people have access to pixel art.

Considerations for BRLTTY: there are a few things that could be implemented in
BRLTTY to help utilize multi-line displays in terminals. The most important of
these is to split long terminal lines on multiple braille lines. For example,
if the terminal width is 80 characters, BRLTTY could use three lines on
Monarch braille display to display one terminal line. Of course BRLTTY could
dynamically choose how many braille lines to use for representing one terminal
line (trimming trailing whitespace).

Sometimes (when reading a table, or playing a grid-based game) it is useful to
move the whole multi-line braille window horizontally. But when reading linear
text (like in text editor, web browser, or output of `ls -l`) the user
probably would like to avoid the horizontal shifts and instead read terminal
contents linearly (even though line breaks in the visual terminal will be in
different points than on the braille display).

This functionality of splitting screen lines on multiple braille lines would
be especially useful for Monarch display, because of its long refresh time,
but I guess it would be very helpful for anyone using a multi-line display.

Another thing that would help Monarch users would be audible notification
before the display is redrawn. Because the display contents will get garbled if
the user touches the display while it is refreshed, it would be nice to have
BRLTTY beep before it refreshes the display so that the user has time to remove
their fingers from the display.

Blinking: due to the long rendering time, all features that utilize blinking
(like blinking cursor, blinking attributes, etc.) must be disabled when using
Monarch.

Line height control: BRLTTY should be able to scale the line height and line
spacing. The user should be able to control how many blank dot rows are left
between lines of text.

One great feature that Monarch (and other similar displays) would allow us to
implement is 10-dot braille. I at least have pushed computer braille to its
limits long time ago and would love to have more dots in my braille cells. The
extra dots could be used for representing terminal attributes or just to be
able to differentiate more characters from each other. Actually, because there
is always an empty vertical column of dots between each character cell, these
dots could also be utilized, resulting in 15-dot braille (3x5 dot cells).
These could be useful in representing line graphics (for example).

Images support: many modern terminals can display images. BRLTTY could add
support for these terminals and display the images on suitable braille
displays.

Finally, I would have two questions for those who have used the other
multi-line displays currently available (Canute 360 and Dotpad): do these
displays have the same issues with refreshing that Monarch has (long refresh
times, garbling of the display if touched during a redraw)? Do these displays
have any way to point to a specific dot (e.g. to route cursor to a particular
position)?

If you have questions regarding Monarch, I can try to answer them.

-- 
Aura