Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Tolerance for lines and polygons - elevation profile #9385

Open
wants to merge 1 commit into
base: master
Choose a base branch
from
Open

Tolerance for lines and polygons - elevation profile #9385

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
15 changes: 13 additions & 2 deletions docs/user_manual/map_views/elevation_profile.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -113,7 +113,8 @@ At the top of the :guilabel:`Elevation Profile` panel, a toolbar provides you wi
- Allows to render distances in the profile chart with units other than the map canvas units.
* - :menuselection:`--> Tolerance`
-
- Sets how far from the actual profile line a point can reside within to be included in the results.
- Sets how far from the actual profile line a feature (point, line, polygon, etc.)
Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

What does "etc." refer to? Here and later

Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

any geometrical object in the future. For now: point, line, polygon, pointcloud. I am not really sure for meshes, but support will be added for polyhedralsurfaces.

can reside to be included in the results.
Uses the map units and is ignored by other layer or geometry types.
* - |dock| :sup:`Dock Elevation Profile View`
-
Expand Down Expand Up @@ -194,8 +195,16 @@ To create a profile view, you can:

#. Under |options| :sup:`Options` drop-down menu, you can set the :guilabel:`Tolerance` value.
This value is used to create a flat buffer around the elevation profile line, visible in the main map canvas.
Any visible point feature overlapping that buffer will be captured in the plot canvas.
Any visible feature (point, line, polygon, etc.) overlapping that buffer will be captured in the plot canvas.

.. note:: **Limitations - Line and polygon extrusion**
Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

@benoitdm-oslandia thanks for the notes. There are a few unclear points to me:

  • "This works fine for points or lines in any case." : what is "this"? The extrusion or its combination with tolerance? Does "in any case" not include 3D lines?
  • "when tolerance is enabled and for 3D lines or 3D polygons, extrusion is not trivial": does 3D refer to layers with z component or is it because of the extrusion output?
  • Then if both 3D(or extruded?) line and polygon geometries are hard to render, why only "Thus, right now, polygon extrusion is disabled when tolerance is enabled."?
  • and trying to get the workflow: a user enables extrusion in elevation properties on a (3D?) polygon layer. Is this option only for the elevation profile purpose? Not for 3D map view? Then he opens a profile view, sets a tolerance, and his extrusion checkbox in the layer properties gets disabled, unknowingly? Not really user friendly IMHO. We should rather somehow ignore the extrusion setting, not disable (meaning to me, uncheck) the user selection. What about his potential 3D map view?

Back to the note, I think we could hide the internal development explanations and simply mention incompatibilities between/disabling/ignoring of polygon extrusion when tolerance is on. And should it be here or in the layer elevations properties, next to the extrusion option?

Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

@benoitdm-oslandia thanks for the notes. There are a few unclear points to me:

* "_This works fine for points or lines in any case._" : what is "this"? The extrusion or its combination with tolerance? Does "in any case" not include 3D lines?

extrusion works fine with points or lines with/without tolerance.

* "_when tolerance is enabled and for 3D lines or 3D polygons, extrusion is not trivial_": does 3D refer to layers with z component or is it because of the extrusion output?

it is about the extrusion output: it becomes an 3D volume we have to reproject in the 2D plane of the profile elevation canvas. This introduces new challenges in object representation as we want to have a fast rendering. Also the current code is not easily understandable nor easily optimizable, this kind of new feature may kill this tool.

* Then if both 3D(or extruded?) line and polygon geometries are hard to render, why only "_Thus, right now, polygon extrusion is disabled when tolerance is enabled._"?

This choice allows to display the intersected objects without having rendering issues.

* and trying to get the workflow: a user enables extrusion in elevation properties on a (3D?) polygon layer. Is this option only for the elevation profile purpose? Not for 3D map view? Then he opens a profile view, sets a tolerance, and his extrusion checkbox in the layer properties gets disabled, unknowingly? Not really user friendly IMHO. We should rather somehow ignore the extrusion setting, not disable (meaning to me, uncheck) the user selection. What about his potential 3D map view?

The checkbox is just ignored (not disabled) when this condition is met: 3D polygon+extrusion+tolerance. The extrusion feature is temporally disabled for this layer.

Back to the note, I think we could hide the internal development explanations and simply mention incompatibilities between/disabling/ignoring of polygon extrusion when tolerance is on. And should it be here or in the layer elevations properties, next to the extrusion option?

I think issue explanation is a good thing for the user as he can understand he asks for something not trivial and it is not a new issue to report.
Also having the explanation in layer elevations properties UI, is a good idea but hard to maintain: we will forget to change it when the code will be fixed.

Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Thanks @benoitdm-oslandia for the feedback

  • Then if both 3D(or extruded?) line and polygon geometries are hard to render, why only "Thus, right now, polygon extrusion is disabled when tolerance is enabled."?

This choice allows to display the intersected objects without having rendering issues.

My point was more about "extruded" line. if both line and polygon geometries are hard to render but we finally disable only polygon, I guess it is because we solve hardness of lines and don't need to mention it in docs anymore. As you replied:

extrusion works fine with points or lines with/without tolerance.

And the title of the note should be adjusted.
Well, trying a rewording to clarify what I meant by "hiding explanations", and taking into account your reply. Hopefully I understand clearly and catch all the key points:

Geometry extrusion can be set in the |elevationscale| :guilabel:Elevation properties of a layer,
and rendered in the profile view. <-- I don't know if rendered is the more accurate word here
When tolerance is enabled, it is however not trivial to render extruded polygons,
thus, right now, polygon extrusion is ignored when tolerance is enabled.
Only the overlap with the 2D geometry of the polygon feature is taken into account.

I added a last line as I understand that it is the extrusion that is ignored, not the polygon which I think is somehow taken into account.

Also having the explanation in layer elevations properties UI, is a good idea but hard to maintain: we will forget to change it when the code will be fixed.

OK. Given that the extrusion is ignored (and not disabled aka unchecked in the elevation properties), this is a tolerance "feature", so we should mention it only in the profile docs.


In the |elevationscale| :guilabel:`Elevation` properties tab of a layer, it is possible to activate the extrusion.
This works fine for points or lines in any case.
However, when tolerance is enabled and for 3D lines or 3D polygons,
extrusion is not trivial because it is equivalent to representing a 3D object
(the 3D polygon is re-projected into a 2D polygon in the elevation profile view but with the extrusion dimension).
Thus, right now, polygon extrusion is disabled when tolerance is enabled.

.. _`elevation_profile_interaction`:

Expand Down Expand Up @@ -321,6 +330,8 @@ to export an elevation profile, allowing you to reuse the plots in another softw
:width: 1.5em
.. |dock| image:: /static/common/dock.png
:width: 1.5em
.. |elevationscale| image:: /static/common/elevationscale.png
:width: 1.5em
.. |fileSaveAs| image:: /static/common/mActionFileSaveAs.png
:width: 1.5em
.. |identify| image:: /static/common/mActionIdentify.png
Expand Down
Loading