Re: Again: canvas size

[Harald H. <h.h...@tu...>]

On Wed, 12 Oct 2005, Ethan Merritt wrote:

> On Wednesday 12 October 2005 02:39 pm, Harald Harders wrote:
> >
> > Until now, the screen coordinates are the only measure (except character,
> > see above) that can remain constant independent on the graph, canvas or
> > whatever size. If the screen coordinate system is changed to be hardcoded
> > to range 0:1 the only absolute coordinate system gets lost.
>
> Then let let us fix that problem directly, instead of mis-using the
> screen size simply to allow specification of arrows in absolute coordinates.
>
> Introduce a new coordinate system "absolute", or maybe even the specific
> units  "in", "cm", "pt", "pixel".

I totally agree with this approach. The specific units have too problems:
How shall pixel defined in vector terminals, and how shall in, ch, pt be
defined in terminals without a absolute canvas size? For png and jpeg, a
resolution in dpi could be given and thus in, ch, and pt also used. But
what about x11 and windows? Do they have access to the system-wide
resolution settings?

> > Where is the advantage of generating two plots with the same size by
> > giving different measures:
> >
> > set terminal png size 640,480
> > set multiplot
> > set size 1,1
> > ...
> >
> > and
> >
> > set terminal png size 640,600
> > set multiplot
> > set size 1,480./600
> >
> > I do not understand this.
>
> If those two command sequences produce the same result, it is a bug.
> But they don't.
>
> The first one produces a 640x480 image that is entirely filled
> by the plot.
>
> The second one produces a 640x600 image that contains a plot
> in the lower 480 pixels, but is blank above that.

Which is the same plot on different canvas (what is the plural of
canvas?). Our do you tell twice the same drawing to be different only
because they are placed in different frames?

> Presumably that
> blank area will be occupied by the next plot in the multiplot
> sequence.  Is that not the entire purpose of multiplot?

Yes, the multiplot command is ment for this. I often use one big plot in
the upper part (which is meant to have the same size as my normal, single
plots) and a smaller plot under it. Here, the automatic placement of
gnuplot cannot work. But let's stop discussing about this because the
abolute measurements are okay for both of us. What do the others say to
that suggestion?

-- 
Harald Harders
h.h...@tu...
http://www.harald-harders.de