xinput: HUION H420 Pen: XChangeDeviceProperty: data: format questions.

[Mike Mestnik]

Plz redirect me to where I can get assistance with this...

Hello,
  Using the xinput cmdline tool I'm fully able to leverage my
understanding of the HUION H420 Pen and it's properties.  When using
xfconf-query I don't believe the data is being constructed correctly
for passing to XChangeDeviceProperty.

https://gitlab.xfce.org/xfce/xfce4-settings/-/blob/bd2da4ed559eec4144ed8ea6092642deee63de9f/xfsettingsd/pointers.c#L866
I'm wondering what the format of this buffer should be?

I'm trying to setup a translation matrix for a tablet(actually the
pen). In xinput I get `Coordinate Transformation Matrix (157):
-1.100000, 0.300000, 1.500000, 0.700000, -1.900000, 1.000000,
0.000000, 0.000000, 1.000000`, the command issued is `xfconf-query -c
pointers -p /HUION_H420_Pen_Pen_0/Properties/Coordinate_Transformation_Matrix
-n -t double -s -1.1 -t double -s 0.2 -t double -s 0.3 -t double -s
0.4 -t double -s 1.5 -t double -s 1.6 -t double -s 0.7 -t double -s
0.8 -t double -s -1.9` Obviously it looks like xfconf-query's backed
is expecting two values per cell?  Because of the code in pointers.c
it's impossible to send more than 9 values, the counts won't match and
the function returns early.  I therefore think that the buffer's
format is incorrectly understood.

I'm looking for clarification on the buffers format.

Thanks.