gnuplot-info

Re: [Gnuplot-info] How to plot directly in unit of pixels by gnuplot?

[Fayer M. <fay...@gm...>]

Yes, I have to, because I want to see pixels clearly.

I found 'digest' in the mailing list is slow. Maybe I shouldn't use this feature? I worry if I choose 'no' in 'Would you like to receive list mail batched in a daily digest', I will get nothing any more. I'm a newbie. Sorry for such questions.

Fayer

> Date: Wed, 21 Jul 2010 05:08:01 -0700 (PDT)
> From: Thomas Sefzick <t.s...@fz...>
> Subject: Re: [Gnuplot-info] How to plot directly in unit of pixels by
> gnuplot?
> To: gnu...@li...
> Message-ID: <292...@ta...>
> Content-Type: text/plain; charset=us-ascii
> 
> 
> did you deactivate the 'Smooth images when zoomed' feature in 'eog'?
> 
> 
> Fayer Michael wrote:
>> 
>> That's exactly what I have tried and failed. What I really want to draw
>> is thousands of thin (big width, small height) rectangles without
>> overlapping but connected (no space between them vertically, but can
>> have space horizontally). They are in different colors and have
>> different width. If I use this kind of relative coordinates (eg.
>> 100/640), the rectangles will overlap vertically a little bit (see code
>> below). That's why I wonder if any methods can use absolute coordinates
>> in pixels to avoid overlapping.
>> 
>> The code:
>> 
>> set cbrange [0:6]
>> set style rect fs solid noborder
>> set xrange [0:1]
>> set yrange [0:1]
>> set key off
>> unset xtics
>> unset ytics
>> unset colorbox
>> set palette defined (0 "black",1 "yellow")
>> set tmargin 0
>> set lmargin 0
>> set bmargin 0
>> set rmargin 0
>> set terminal png size 10,10
>> set output "tt.png"
>> set obj rect from 0,0 to 0.5,0.5 fc palette cb 3
>> set obj rect from 1,1 to 0.5,0.5 fc palette cb 6
>> plot -1 lc palette cb 1 # invisible, to show content above
>> replot
>> 
>> By using 'eog', one can zoom in the png file up to 2000%, and see two
>> rectangles are overlapped (although mathmetically they should not
>> overlap) and the edges/frames also are not 'tidy'.
>> 
>>> Date: Tue, 20 Jul 2010 10:32:23 -0700 (PDT)
>>> From: Thomas Sefzick <t.s...@fz...>
>>> Subject: Re: [Gnuplot-info] How to plot directly in unit of pixels by
>>> gnuplot?
>>> To: gnu...@li...
>>> Message-ID: <292...@ta...>
>>> Content-Type: text/plain; charset=us-ascii
>>> 
>>> 
>>> use the screen coordinates when defining objects:
>>> 
>>> set term gif size 640,480
>>> set obj 1 rect from screen 100./640.,20./480. to screen
>>> 200./640.,30./480.
>>> fc palette cb 3
>>> set out 'plot.gif'
>>> plot sin(x)
>>> set out
>>> 
>>> 
>>> Fayer Michael wrote:
>>> > 
>>> > Except for canvas size, gnuplot uses relative unit to plot. Now I want
>>> > to draw directly in unit of pixels. For example, I want something like:
>>> >   set obj rect from 100,20 to 200,30 fc palette cb 3
>>> > 
>>> > where 100,20 and 200,30 are in pixel.
>>> > 
>>> > I set xrange/yrange to something like 1:640 and 1:480, and set all
>>> > margins to 0. However, the results were still not exactly what I want.
>>> > And it's a dirty hack. Anyone knows a clean one?
>>> > 
>>> > I noticed low-level Perl package Term::Gnuplot, but it's not convenient
>>> > for high-level plotting.
>>> > 
>>> > Fayer

Re: [Gnuplot-info] How to plot directly in unit of pixels by gnuplot?

[Fayer M. <fay...@gm...>]

Anyone has further comments on this issue?

BTW, I have found 'No digest' will get emails separately without
missing.

Fayer


> Date: Sat, 24 Jul 2010 07:34:47 +0800
> From: "Fayer Michael" <fay...@em...>
> Subject: Re: [Gnuplot-info] How to plot directly in unit of pixels by
> 	gnuplot?
> To: <gnu...@li...>
> Message-ID: <A8C2676799324C6583B740607AC48323@arara>
> Content-Type: text/plain;	charset="iso-8859-1"
> 
> Yes, I have to, because I want to see pixels clearly.
> 
> I found 'digest' in the mailing list is slow. Maybe I shouldn't use this feature? I worry if I choose 'no' in 'Would you like to receive list mail batched in a daily digest', I will get nothing any more. I'm a newbie. Sorry for such questions.
> 
> Fayer
> 
> > Date: Wed, 21 Jul 2010 05:08:01 -0700 (PDT)
> > From: Thomas Sefzick <t.s...@fz...>
> > Subject: Re: [Gnuplot-info] How to plot directly in unit of pixels by
> > gnuplot?
> > To: gnu...@li...
> > Message-ID: <292...@ta...>
> > Content-Type: text/plain; charset=us-ascii
> > 
> > 
> > did you deactivate the 'Smooth images when zoomed' feature in 'eog'?
> > 
> > 
> > Fayer Michael wrote:
> >> 
> >> That's exactly what I have tried and failed. What I really want to draw
> >> is thousands of thin (big width, small height) rectangles without
> >> overlapping but connected (no space between them vertically, but can
> >> have space horizontally). They are in different colors and have
> >> different width. If I use this kind of relative coordinates (eg.
> >> 100/640), the rectangles will overlap vertically a little bit (see code
> >> below). That's why I wonder if any methods can use absolute coordinates
> >> in pixels to avoid overlapping.
> >> 
> >> The code:
> >> 
> >> set cbrange [0:6]
> >> set style rect fs solid noborder
> >> set xrange [0:1]
> >> set yrange [0:1]
> >> set key off
> >> unset xtics
> >> unset ytics
> >> unset colorbox
> >> set palette defined (0 "black",1 "yellow")
> >> set tmargin 0
> >> set lmargin 0
> >> set bmargin 0
> >> set rmargin 0
> >> set terminal png size 10,10
> >> set output "tt.png"
> >> set obj rect from 0,0 to 0.5,0.5 fc palette cb 3
> >> set obj rect from 1,1 to 0.5,0.5 fc palette cb 6
> >> plot -1 lc palette cb 1 # invisible, to show content above
> >> replot
> >> 
> >> By using 'eog', one can zoom in the png file up to 2000%, and see two
> >> rectangles are overlapped (although mathmetically they should not
> >> overlap) and the edges/frames also are not 'tidy'.
> >> 
> >>> Date: Tue, 20 Jul 2010 10:32:23 -0700 (PDT)
> >>> From: Thomas Sefzick <t.s...@fz...>
> >>> Subject: Re: [Gnuplot-info] How to plot directly in unit of pixels by
> >>> gnuplot?
> >>> To: gnu...@li...
> >>> Message-ID: <292...@ta...>
> >>> Content-Type: text/plain; charset=us-ascii
> >>> 
> >>> 
> >>> use the screen coordinates when defining objects:
> >>> 
> >>> set term gif size 640,480
> >>> set obj 1 rect from screen 100./640.,20./480. to screen
> >>> 200./640.,30./480.
> >>> fc palette cb 3
> >>> set out 'plot.gif'
> >>> plot sin(x)
> >>> set out
> >>> 
> >>> 
> >>> Fayer Michael wrote:
> >>> > 
> >>> > Except for canvas size, gnuplot uses relative unit to plot. Now I want
> >>> > to draw directly in unit of pixels. For example, I want something like:
> >>> >   set obj rect from 100,20 to 200,30 fc palette cb 3
> >>> > 
> >>> > where 100,20 and 200,30 are in pixel.
> >>> > 
> >>> > I set xrange/yrange to something like 1:640 and 1:480, and set all
> >>> > margins to 0. However, the results were still not exactly what I want.
> >>> > And it's a dirty hack. Anyone knows a clean one?
> >>> > 
> >>> > I noticed low-level Perl package Term::Gnuplot, but it's not convenient
> >>> > for high-level plotting.
> >>> > 
> >>> > Fayer

Re: [Gnuplot-info] How to plot directly in unit of pixels by gnuplot?

[Fayer M. <fay...@gm...>]

I have found the answer. This mail is just for anyone who has same
problem.

Gnuplot may not be a good choice for abstract coordinate plotting. For
such purpose, ImageMagick is a perfect choice. Of course, ImageMagick is
a far more useful tool.

To draw two stacked but non-overlapped rectanges, if one use PerlMagick,
a simple but fully functional sample code can be as below:


use Image::Magick;
my $o=Image::Magick->new;
$o->Set(size=>'10x10');
$o->Read('xc:transparent'); # canvas color
$o->Draw(primitive=>'rectangle',points=>'6,6
9,9',fill=>'hsb(16.6667%,100%,100%)'); # yellow
$o->Draw(primitive=>'rectangle',points=>'3,3
7,5',fill=>'hsb(16.6667%,100%,60%)'); # dark yellow
$o->Write('test.gif');


Fayer


On Tue, 2010-07-27 at 08:49 +0800, Fayer Michael wrote:
> Anyone has further comments on this issue?
> 
> BTW, I have found 'No digest' will get emails separately without
> missing.
> 
> Fayer
> 
> 
> > Date: Sat, 24 Jul 2010 07:34:47 +0800
> > From: "Fayer Michael" <fay...@em...>
> > Subject: Re: [Gnuplot-info] How to plot directly in unit of pixels by
> > 	gnuplot?
> > To: <gnu...@li...>
> > Message-ID: <A8C2676799324C6583B740607AC48323@arara>
> > Content-Type: text/plain;	charset="iso-8859-1"
> > 
> > Yes, I have to, because I want to see pixels clearly.
> > 
> > I found 'digest' in the mailing list is slow. Maybe I shouldn't use this feature? I worry if I choose 'no' in 'Would you like to receive list mail batched in a daily digest', I will get nothing any more. I'm a newbie. Sorry for such questions.
> > 
> > Fayer
> > 
> > > Date: Wed, 21 Jul 2010 05:08:01 -0700 (PDT)
> > > From: Thomas Sefzick <t.s...@fz...>
> > > Subject: Re: [Gnuplot-info] How to plot directly in unit of pixels by
> > > gnuplot?
> > > To: gnu...@li...
> > > Message-ID: <292...@ta...>
> > > Content-Type: text/plain; charset=us-ascii
> > > 
> > > 
> > > did you deactivate the 'Smooth images when zoomed' feature in 'eog'?
> > > 
> > > 
> > > Fayer Michael wrote:
> > >> 
> > >> That's exactly what I have tried and failed. What I really want to draw
> > >> is thousands of thin (big width, small height) rectangles without
> > >> overlapping but connected (no space between them vertically, but can
> > >> have space horizontally). They are in different colors and have
> > >> different width. If I use this kind of relative coordinates (eg.
> > >> 100/640), the rectangles will overlap vertically a little bit (see code
> > >> below). That's why I wonder if any methods can use absolute coordinates
> > >> in pixels to avoid overlapping.
> > >> 
> > >> The code:
> > >> 
> > >> set cbrange [0:6]
> > >> set style rect fs solid noborder
> > >> set xrange [0:1]
> > >> set yrange [0:1]
> > >> set key off
> > >> unset xtics
> > >> unset ytics
> > >> unset colorbox
> > >> set palette defined (0 "black",1 "yellow")
> > >> set tmargin 0
> > >> set lmargin 0
> > >> set bmargin 0
> > >> set rmargin 0
> > >> set terminal png size 10,10
> > >> set output "tt.png"
> > >> set obj rect from 0,0 to 0.5,0.5 fc palette cb 3
> > >> set obj rect from 1,1 to 0.5,0.5 fc palette cb 6
> > >> plot -1 lc palette cb 1 # invisible, to show content above
> > >> replot
> > >> 
> > >> By using 'eog', one can zoom in the png file up to 2000%, and see two
> > >> rectangles are overlapped (although mathmetically they should not
> > >> overlap) and the edges/frames also are not 'tidy'.
> > >> 
> > >>> Date: Tue, 20 Jul 2010 10:32:23 -0700 (PDT)
> > >>> From: Thomas Sefzick <t.s...@fz...>
> > >>> Subject: Re: [Gnuplot-info] How to plot directly in unit of pixels by
> > >>> gnuplot?
> > >>> To: gnu...@li...
> > >>> Message-ID: <292...@ta...>
> > >>> Content-Type: text/plain; charset=us-ascii
> > >>> 
> > >>> 
> > >>> use the screen coordinates when defining objects:
> > >>> 
> > >>> set term gif size 640,480
> > >>> set obj 1 rect from screen 100./640.,20./480. to screen
> > >>> 200./640.,30./480.
> > >>> fc palette cb 3
> > >>> set out 'plot.gif'
> > >>> plot sin(x)
> > >>> set out
> > >>> 
> > >>> 
> > >>> Fayer Michael wrote:
> > >>> > 
> > >>> > Except for canvas size, gnuplot uses relative unit to plot. Now I want
> > >>> > to draw directly in unit of pixels. For example, I want something like:
> > >>> >   set obj rect from 100,20 to 200,30 fc palette cb 3
> > >>> > 
> > >>> > where 100,20 and 200,30 are in pixel.
> > >>> > 
> > >>> > I set xrange/yrange to something like 1:640 and 1:480, and set all
> > >>> > margins to 0. However, the results were still not exactly what I want.
> > >>> > And it's a dirty hack. Anyone knows a clean one?
> > >>> > 
> > >>> > I noticed low-level Perl package Term::Gnuplot, but it's not convenient
> > >>> > for high-level plotting.
> > >>> > 
> > >>> > Fayer