[PATCH v3 app/xrandr] Document that --dpi and --fbmm options set DPI of whole X screen

[Giuseppe Bilotta]

On Sat, Mar 10, 2018 at 4:23 PM, Pali Rohár <pali.rohar at gmail.com> wrote:
> Explicitly document and make it clear that those options do not change
> DPI of some monitor output. Also state that these options have no useful
> meaning for multi-monitor configuration.
>
> Signed-off-by: Pali Rohár <pali.rohar at gmail.com>

FWIW,

Reviewed-by: Giuseppe Bilotta <giuseppe.bilotta at gmail.com>

> ---
>  man/xrandr.man | 19 +++++++++++++++----
>  1 file changed, 15 insertions(+), 4 deletions(-)
>
> diff --git a/man/xrandr.man b/man/xrandr.man
> index aa82724..1291bad 100644
> --- a/man/xrandr.man
> +++ b/man/xrandr.man
> @@ -257,14 +257,25 @@ fit within this size. When this option is not provided, xrandr computes the
>  smallest screen size that will hold the set of configured outputs; this
>  option provides a way to override that behaviour.
>  .IP "\-\-fbmm \fIwidth\fPx\fIheight\fP"
> -Sets the reported values for the physical size of the screen. Normally,
> +Sets the value reported as physical size of the X screen as a whole
> +(union of all configured monitors). In configurations with multiple
> +monitors with different DPIs, the value has no physical meaning, but
> +it may be used by some legacy clients which do not support RandR
> +version 1.2 to compute a reference font scaling. Normally,
>  xrandr resets the reported physical size values to keep the DPI constant.
> -This overrides that computation.
> +This overrides that computation. Default DPI value is 96.
>  .IP "\-\-dpi \fIdpi\fP"
>  .IP "\-\-dpi \fIfrom-output\fP"
> -This also sets the reported physical size values of the screen, it uses either
> +This also sets the value reported as physical size of the X screen as a whole
> +(union of all configured monitors). In configurations with multiple
> +monitors with different DPIs, the value has no physical meaning, but
> +it may be used by some legacy clients which do not support RandR
> +version 1.2 to compute a reference font scaling. This option uses either
>  the specified DPI value, or the DPI of the given output, to compute an appropriate
> -physical size using whatever pixel size will be set.
> +physical size using whatever pixel size will be set. Typical values are
> +the default (96 DPI), the DPI of the only monitor in single-monitor
> +configurations, or the DPI of the primary monitor in multi-monitor
> +configurations.
>  .IP "\-\-newmode \fIname\fP \fImode\fP"
>  New modelines can be added to the server and then associated with outputs.
>  This option does the former. The \fImode\fP is specified using the ModeLine
> --
> 2.11.0
>



-- 
Giuseppe "Oblomov" Bilotta