lkml.org 
[lkml]   [2006]   [May]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: How should Touchscreen Input Drives behave (OpenEZX pcap_ts)
Harald Welte wrote:
> 0) What kind of X/Y/Pressure values should I return? Are they supposed
> to be scaled to the X/Y resolution of the LCD? As of now, I return
> X_ABS, Y_ABS and PRESSURE values between 0 and 1000 (each).
>
> However, the coordinates are actually inverted, so '0,0' corresponds
> to the lower right corner of the screen, whereas '1000,1000' is the
> upper left corner. Shall I invert them (i.e. return 1000-coord')?

The native driver reports pressure as either 65535 or 0, and doesn't
(seem to) scale the x/y values at all. The uncalibrated values and
180 degree rotation (actually, my phone shows a slight rotation error
or a few pixels) are definitely reported to user space without
modification.

A matrix-based recalibrator will handle any orientation so long as the
corners are known, and so long as you report a pressure of zero
meaning "pen up" everything should be compatible regardless of the
units you choose.

Andy
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-05-18 18:20    [W:0.078 / U:16.112 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site