Re: [Xenomai] Heads up: I-pipe patch status on ARM

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

On 07/29/2012 02:49 PM, xenophile wrote:

> On 07/29/12 14:02, Gilles Chanteperdrix wrote:
>> On 07/29/2012 01:50 PM, xenophile wrote:
>>
>>> On 07/29/12 13:22, Gilles Chanteperdrix wrote:
>>>> On 07/29/2012 01:09 PM, xenophile wrote:
>>>>
>>>>> bitmap rendered graphs should be a relic of  the 1990's ;)
>>>>
>>>>
>>>> ... but still look much better without getting to much in gnuplot
>>>> configuration:
>>>> http://sisyphus.hd.free.fr/~gilles/core-3.4-latencies/atom.png
>>>> http://sisyphus.hd.free.fr/~gilles/core-3.4-latencies/atom.svg
>>>>
>>>
>>> There is a problem  with the legend not showing for some reason. If
>>> you'd like to send me your gnuplot script and a sample data file I could
>>> look what is going wrong. (Off list if you prefer).
>>>
>>> You may want to explicitly specify the font size as well since it seems
>>> you prefer the smaller text in the png.
>>>
>>> Apart from fixing the problem with the legend , where's the "much better"?
>>>
>>> Your gnuplot has standalone="no" at the top so you do have a version
>>> that can have the interactive features I suggested.
>>>
>>> In particular toggling lines on/off can be a useful feature with this
>>> kind of multiple line plot.
>>>
>>> Your svg doesn't  zoom either :?
>>>
>>
>>
>> Well, the lines are to thick, the fonts are to large, so large that the
>> legend can not be printed (but it is a placement issue due to my script,
> 
> so specify the line width and text size you'd like. There is not an 
> exact 1:1 mapping of line widths between how png and svg render finally.


> 
> Also fonts are created on the host machine in the case of png whereas 
> the choice of font is done in the viewer with formats like svg, 
> postscript , pdf which provide text descriptions not dots. It will 

> probably help to explicitly define the font

I understand that. And I see a problem here, depending on how the graph
is scaled, the legend may fit or not, even depending on what font the
client chose as substitute of a font not present on the client side.

As for the line width, I would like it to be 1 pixel whatever the zoom
factor or screen size. This does not look very "vector like", but after
all lines are the representation of something which has a null width, so
should be represented with the smallest possible width: 1 pixel. I see
here some "smoothing" of the line despite the fact that I have set the
linewidth to "1", so I guess the client is in fact adding the smoothing.

> 
>> I know how to fix that), so, overall the graph looks really ugly. The
>> svg graph zooms with my client.
> 
> which is ?
> 
> Tested you links on linux firefox-14 and Opera . Mine zoom ,yours don't :?


I meant that it was automatically resized when I maximize the browser
window. That is what I meant by "it zooms". Without "terminal svg
dynamic", it does not rescale automatically.

> gnuplot> help svg:
> ...
>   `dynamic` allows a svg-viewer to resize plot, whereas the default
>   setting, `fixed`, will request an absolute size.
> 
> You are inviting the viewer to autoscale, which effectively defeating 
> the one of the (potential) benefits of using a scalable format. Opera 
> shows in it's scaling widget that it is zooming but then autoscales the 
> svg so that I get the same thing on screen.
> 
> Since most browsers now seem to autoscale when first showing a graphic 
> even if you don't request it , leaving this out is probably the best 

> option. This may have a bearing on your font size issues too.

Does not work here, my firefox is probably too old (something like
version 10).

> 
>>
>> The script is based on scripts/histo.gp in xenomai distribution, with
>> simply "set terminal png..." replaced with "set terminal svg dynamic".
>> I would gladly accept a patch to this file which makes it render good
>> looking svg graphs.
>>
> 
> I don't have xeno installed an any hardware here but I am willing to 
> help you get clean output if you want to link me the script and a sample 
> data file.
> 
> I am active on gnuplot ML and was behind getting a lot of this stuff 
> into gnuplot.
> 
> eg.
> set terminal svg mouse standalone  font arial 7


arial is just the font that may not be present on everybody's
installation. My gnuplot is simply too old (4.4) for this line to work,
neither mouse, nor standalone work here, and the font syntax is different.

All things considered, I am not so sure svg is such a big win.

The script and data I use to build the graph are all in
http://sisyphus.hd.free.fr/~gilles/core-3.4-latencies
starting from
http://sisyphus.hd.free.fr/~gilles/core-3.4-latencies/histo.gp

-- 
                                                                Gilles.