[Kst] [Bug 299788] New: Plot axis ranges are off by one pixel

[D. V. Wiebe]

https://bugs.kde.org/show_bug.cgi?id=299788

Bug ID: 299788
Severity: normal
Version: 2.0.4
Priority: NOR
Assignee: ***@kde.org
Summary: Plot axis ranges are off by one pixel
Classification: Unclassified
OS: Linux
Reporter: ***@ketiltrout.net
Hardware: Compiled Sources
Status: UNCONFIRMED
Component: view objects
Product: kst

When setting plot limits to fixed values, the lower X limit is plotted one
pixel to the right of the left edge of the plot. Similarly, the upper Y limit
is plotted one pixel below the top of the plot.

Reproducible: Always

Steps to Reproduce:
1. Create a new plot object.
2. Fix the limits of the plot (Edit Plot Item -> Range/Zoom -> X/Y Zoom Mode
-> Fixed) to values which will induce major ticks on the edges of the plots.
For instance, use from 0 to 1 for both X and Y axes.
Actual Results:
The 0 tick mark and grid line of the X axis is one pixel to the right of the
left border of the plot. Similary, the 1 tick mark and grid line of the Y axis
is one pixel below the top border of the plot.

Expected Results:
The left and top plot range limits should correspond to the edges of the plot,
as the bottom and right limits do.

[D. V. Wiebe]

https://bugs.kde.org/show_bug.cgi?id=299788

--- Comment #1 from D. V. Wiebe <***@ketiltrout.net> ---
Created attachment 71013
--> https://bugs.kde.org/attachment.cgi?id=71013&action=edit
Test plot showing the bug.

Here's a exported PNG showing the bug following the steps outlined above. Note
spurious tick marks in the bottom left, top left (two), and top right corners
of the plot, as well as dotted grid lines along the top and left side of the
plot.

[Ben Lewis]

I think this is related....

The left plot boarder is missing when the option to hide left margin is selected (Edit Plot Item >
Y-Axis > Hide Left). See attached screen shot.

This behaviour is new to 2.0.5

Ben

Post by D. V. Wiebe
https://bugs.kde.org/show_bug.cgi?id=299788
Created attachment 71013
--> https://bugs.kde.org/attachment.cgi?id=71013&action=edit
Test plot showing the bug.
Here's a exported PNG showing the bug following the steps outlined above. Note
spurious tick marks in the bottom left, top left (two), and top right corners
of the plot, as well as dotted grid lines along the top and left side of the
plot.

[n***@astro.utoronto.ca]

https://bugs.kde.org/show_bug.cgi?id=299788

***@astro.utoronto.ca changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |***@astro.utoronto.
| |ca

--- Comment #2 from ***@astro.utoronto.ca ---
Which behavior (top left, or bottom right) is more appropriate?

In the bottom right behavior, a line which defines the boundry of the region is
not seen. In the top-left behavior, it is.

I sort of like the top-left behavior.

[D. V. Wiebe]

https://bugs.kde.org/show_bug.cgi?id=299788

--- Comment #3 from D. V. Wiebe <***@ketiltrout.net> ---
Yeah, I seem I recall you advocating top-left in the past.

I'm going to argue for bottom-right, for the simple fact that it's easier to
emulate top-left if BR is the default (just add epsilon to your limits), but
much harder to get BR if kst does TL, since in that case you have to figure out
how big a pixel is in axis unit, which requires knowing the size of the plot in
pixels.

[n***@astro.utoronto.ca]

https://bugs.kde.org/show_bug.cgi?id=299788

***@astro.utoronto.ca changed:

What |Removed |Added
----------------------------------------------------------------------------
Priority|NOR |VLO

--- Comment #4 from ***@astro.utoronto.ca ---
Described differently, the current implementation is
[xmin, xmax)

That is, a value of xmin is shown in the plot, but a value of xmax is not.

However: the data do agree with the plot ticks. The only bug here is that the
plot is 1 pixel wider than is asked for (or 1 pixel narrower, depending what
you think you asked for) . This is completely invisible for vector based
outputs - where you might actually care.

So it is unlikely that we will fix this any time soon.

[Andrew Crouthamel]

https://bugs.kde.org/show_bug.cgi?id=299788

Andrew Crouthamel <***@kdemail.net> changed:

What |Removed |Added
----------------------------------------------------------------------------
Status|REPORTED |NEEDSINFO
Resolution|--- |WAITINGFORINFO

--- Comment #5 from Andrew Crouthamel <***@kdemail.net> ---
Dear Bug Submitter,

This bug has been stagnant for a long time. Could you help us out and re-test
if the bug is valid in the latest version? I am setting the status to NEEDSINFO
pending your response, please change the Status back to REPORTED when you
respond.

Thank you for helping us make KDE software even better for everyone!

[Andrew Crouthamel]

https://bugs.kde.org/show_bug.cgi?id=299788

Andrew Crouthamel <***@kdemail.net> changed:

What |Removed |Added
----------------------------------------------------------------------------
Resolution|WAITINGFORINFO |---
Status|NEEDSINFO |REPORTED

--- Comment #6 from Andrew Crouthamel <***@kdemail.net> ---
Dear Bug Submitter,

This is a reminder that this bug has been stagnant for a long time. Could you
help us out and re-test if the bug is valid in the latest version? This bug
will be moved back to REPORTED Status for manual review later, which may take a
while. If you are able to, please lend us a hand.

Thank you for helping us make KDE software even better for everyone!