Tag: uncategorized

This year’s user conference took place in Bratislava, organized by the Slovak QGIS User Group and hosted at the Slovak University of Technology Faculty of Civil Engineering. The event was sold out early and the venue was full of energy and excitement.

If you missed the conference or couldn’t make it to a talk due to too many great overlapping sessions, you now have the opportunity to catch up with everything on the UC 2024 playing list:

Thanks to the organizers, speakers, sponsors, and all participants for the wonderful event.

If you want to read some personal reports from community members, here’s Ujaval Gandhi’s report: https://spatialthoughts.com/2024/09/14/qgis-user-conference-2024; and here’s Hans van der Kwast’s: https://www.qwast-gis.com/l/qgis-user-conference-2024/

Last but not least, we want you to save the date for next year’s user conference:

The QGIS User Conference will be in Norrköping, Sweden from 2-3 June 2025, and contributor meeting there after 4-7.

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The heart of the effect involves the very clever idea of using the topographic layer as a subtle opacity mask to simulate mist, fog and atmospheric haze. Have a look at the image below taken on March 17th, 2005 by NASA’s Terra satellite. This is the industrialised Po valley of northern Italy, surrounded by the Alps and Apennine Mountains that rise above the valley’s hazy pollution. The haze adds a sense of depth to the surrounding hills and mountains. It’s not uncommon to see fog and pollution in satellite imagery that gives way to the clear air in high mountains e.g. northern India and Nepal, China, Pakistan and India. Creating a similar mist effect in QGIS is actually quite simple.

First download topography for the Alps and Po region (a 68.55 Mb GeoTiff file derived from freely available EU-DEM data I resampled from 25 to 100m resolution). Next, make sure you have the plugin QuickMapServics (QMS) installed (menu Plugins – Manage and Install Plugins). This great plugin provides access to over 1000 basemaps.

Load the GeoTiff file into QGIS (Raster – Load) and rename the layer Hillshade. Right click the layer to open the Layer Properties window. In the Symbology panel, next to Render Type, choose Hillshade. Change the altitude to 35 degrees, Azimuth to 300 degrees and Z Factor of 1.5 (illuminating the landscape from the top left). Finally, change the Blending mode to Multiply. Click OK to close the dialogue.

To add the basemap layer, Esri World Imagery (Clarity), type “ESRI clarity” in the QMS search bar to find and add the basemap; Go to View – Panels and activate the QMS search bar if it isn’t initially visible. Make sure it’s the bottommost layer.

Oh, that’s a bit disappointing, we only increased the relief little a bit. It’s missing the vitally important mist layer.

To create mist, right click the Hillshade layer and choose Duplicate. Rename the new layer Mist and make sure it’s above the Hillshade layer. Now open the Layer Properties window of the layer, we’re going edit it’s attributes to make it look like mist.

Change the Render type to Singleband Pseudocolor and use 0 and 3000 for the min and max values (limiting maximum latitude of the mist to 3000 meters). Then open the colour ramp window by clicking on the Color ramp and enter these values:

• Left Gradient – HSV 215 15 50 and 75% transparency
• Right Gradient – HSV 215 15 50 and 0% transparency

Close the Color Ramp dialogue. In the Layer Properties window, and this is very important, change the Blending mode to Lighten. Click OK to close the Layer Properties window.

Wow, we have mist!

(View Full Size)

The mist effect looks great. It certainly adds a lot of realism to the topographic map, it now looks quite like NASA’s images. This is just a quick and basic map so there’s lots of scope to improve the effect. Play around with the colour of the mist layer and its opacity, or even brighten the Hillshade layer underneath. See what effects these changes have.

Here’s another example below. In this example I duplicated the hillshade layer and set the second hillshade layer to Multidirectional Hillshading (yes, QGIS 3.2 has Multidirectional Hillshading). I then adjusted the transparency of both hillshade layers so they blended together nicely. I then replaced the basemap with another duplicated topography layer that I coloured using the gradient sd-a (by Jim Mossman, 2005) using the cpt-city plugin. And lastly, I doubled the opacity of the mist layer turning it into a milky fog. I think it looks great!

(View Full Size)

What next? Well, there’s lots of possibilities. Perhaps download Martian topography and add mist to the bottom of Valles Marineris?

References:

Eduard Imhof – Biography

TV documentary about Eduard Imhof

The Map as an Artistic Territory: Relief Shading Works and Studies by Eduard Imhof

Haze in northern Italy – NASA Terra Satellite

You may have seen my earlier tutorial where I described how to make nice looking hillshaded maps in QGIS using SRTM elevation data. Well, we don’t have to stop with just one hillshade layer on a map, it is possible to overlay multiple hillshades; a procedure that can increase the visual quality and detail. The following image is the hillshade we made before. Once you re-create a hillshade, following the previous tutorial, you can head to the next step (note that brightness and contrast settings may be different due to changes in how QGIS generates and displays hillshades).

We can improve the SRTM hillshade further by adding ESRI’s World Hillshade layer, which uses multi-directional illumination (also called a Swiss Hillshade in tribute to the celebrated Swiss cartographer Eduard Imhof). In addition, World Hillshade has a much higher resolution than SRTM 30m data in some regions of the world, it is 2m for most of the England and Wales, 10m for most of the US, 5m for Spain and 3m for Holland etc. The only drawback is that the style of this layer is somewhat controversial, some love it, some hate it, it looks like it’s illuminated from above, but mixing it with the SRTM hillshade obviates some of it criticised flaws.

To add the World Hillshade layer in QGIS go to the Layer Menu – Add Layer – Add ArcGIS MapServer Layer – click New and add the following URL:

https://services.arcgisonline.com/arcgis/rest/services/Elevation/World_Hillshade/MapServer

Notice QGIS 2.18 no longer needs a plugin to add ESRI layers, it new has this functionality built in. Also, open the url in a browser such as Firefox, it brings up a webpage that describes the layer. We also see links to other other layers. Yes, they can all be added to QGIS by simply taking the URL of the webpage that describe the layer and connecting to it via the ArcGIS MapServer Layer connector.

Name the layer World Hillshade and click Connect, then click and highlight the layer it connects to. Finally, click the Add button to add the layer to the canvas.

Next, we need to adjust the properties of the World Hillshade layer to properly overlay it above the SRTM hillshade layer. Make sure the World hillshade layer is the topmost layer. In the Layers Panel, right click Layer properties and in the window that opens up, click Style (if not visible). Next, change the Layer Blending mode (under color rendering) to Overlay. Adjust the layer’s brightness to around -20 and leave contrast at 0. If you find the scene is still too dark, brighten the SRTM Hillshade by increasing the layer’s brightness. You may also have to change (lower) the Min value of the Min – Max value boxes. Leave the contrast at 0 for the SRTM hillshade. Also, don’t brighten it too much as it might become washed out, loose detail, especially in bright areas. Play around the controls, settings may vary depending on the SRTM data you download and the version of QGIS you use.

Here’s a comparison in Ireland, a ring like structure of hills with a central peak. No, it’s not a meteorite crater. It’s a different kind of geological marvel, the Slieve Gullion Complex and its ring dyke; the deeply eroded remains of a 410 million year old Caledonian volcano. The SRTM hillshade is on the left and World Hillshade + SRTM hillshade is on the right (click on the image, it’s best appreciated full size):

We can see the World Hillshade + SRTM Hillshade layer shows much finer detail. We see a parallel array of roughly north-south orientated lines, these are fractures and faults that cut the Slieve Gullion Complex that were perhaps enhanced by glacial erosion. Also, look carefully, there seems to be some roads meandering across the landscape (hint, bottom of the map and right of the scale bar). You should get even better results with higher resolution World Hillshade data. We also notice that bending SRTM derived hillshade with World Hillshade adds a naturalistic illumination not apparent in multi-directional hillshading. So we have the best of both worlds, a high resolution hillshade and realistic looking illumination.

Hope you found this tutorial helpful.

References:

Baxter, S., 2008. A Geological Field Guide to Cooley Gullion, Mourne & Slieve Croob [pdf]. Geological Survey of Ireland, Dublin. p. 43-53.

A year ago I have asked QGIS’s community what were their favourite QGIS new features from 2015 and published this blog post. This year I decided to ask it again. In 2016, we add the release of the second long-term release (2.14 LTR), and two other stable versions (2.16 and 2.18).

2016 was again very productive year for the QGIS community, with lots of improvements and new features landing on QGIS source code, not to speak of all the work already in place for QGIS 3. This is a great assurance of the project’s vitality.

As a balance, I have asked users to choose wich were their favorite new features during 2016 (from the visual changelogs list). As a result, I got the following Top 5 features list.

5 – Paste a style to multiple selected layers or to all layers in a legend group (2.14)

This is a productivity functionaly that I just realized that existed now, with so many people voting on it. If copy/paste styles was, in my opinion, a killer feature, being able to use it in multiple layers or even a group is just great.

4 – fTools plugin has been replaced with Processing algorithms (2.16)

While checking the Vector Menu, the tools seem the same as previous version, but it’s when you open them that you understand the difference. All vector tools, provided until now by the fTools core plugin, were replaced by equivalent processing Algoritms. For the users it means easier access to more functionality, like running the tools in batch mode, or getting outputs as temporary layers. Besides some of the tools have been improved.

3 – Virtual layers (2.14)

This is definitly one of my favourite new features, and it seems I’m not alone. With virtual layers you can run SQL queries using the layers loaded in the project, even when the layers are not stored in a relational database. We are not talking about WHERE statments to filter data, with this you can do real SQL queries, with spatial analysis, aggregations, and so on. Besides, virtual layers will act as VIEWs and any changes to any of the input layers will automatically update the layer.

2 – Speed and memory improvements (2.14)

It’s no surprise that speed and memory improvements we one of the most voted features. Lots of improvements were made for loading and managing large datasets, and this have a tremendous impact in all users. According to the changelog, zoom is faster, selecting features is faster, updating attributes on selected features is faster, and it consumes less memory. So don’t be afraid to put QGIS to the test.

1 – Trace digitising tool (2.14)

If you do lots of digitising, you better look into this new feaure that landed on QGIS 2.14. It allows you to digitize new feature by using other layers boundaries. Besides the quality improvement of layers topology, this can make digitizing almost feel pleasing and fast! Just click the first point, move your mouse around other features edged to pick up more vertex.

There were other new features that also made the delight of many users. For example, several improvements on the labeling, Georeference outputs (eg PDF) from composer (2.16), Filter legend by expression (2.14), 2.5D Renderer. Personally, the Style docker made my day/year. But you can check the full results of the survey, if you like.

Obviously, this list means nothing at all. All new features were of tremendous value, and will be useful for thousands (yes thousands) of people. It was a mere exercise as, with such a diverse QGIS crowd, it would be impossible to build a list that would fit us all. Besides, there were many great enhancements, introduced during 2016, that might have fallen under the radar for most users. Check the visual changelogs for a full list of new features.

On my behalf, to all developers, sponsors, and general QGIS contributors, once again

THANK YOU VERY MUCH FOR YOUR TREMENDOUS WORK!

I wish you a fantastic 2017.

Yesterday Dartmoor National Park was host to the third QGIS user group for the South West region. We a great range of talks from the worlds of academia, offshore exploration and local government to name but a few. The slides from these are below.

Teaching in QGIS

Using PostGIS within our Geospatial Workflows at Lloyd’s Register

The Adoption of QGIS at Plymouth Community Homes

Integrating QGIS functionality into a data workflow through both automated processing and a plugin

PopChange: An Academic Open Source Project

Building a Mixed GIS Environment at the Met Office

We are looking at having another meet up in the spring and are thinking of running some workshops on form designing and plugin building. Keep an eye on the main QGIS user group page on Google+ for any news.

Thanks again to everyone who attending and presented.  We also need to give a special thanks to Clear Mapping Company for sponsoring the event.

Cheers

Matt

(aka Features that ArcGIS Desktop users might not know that exists)

EN | PT

From time to time, I read articles comparing ArcGIS vs QGIS. Since many of those articles are created from an ArcGIS user point of view, they invariably lead to biased observations on QGIS lack of features. It’s time for a QGIS user perspective, so bare with me on this (a bit) long, totally and openly biased post.

“Hello, my name is Alexandre, and I have been using… QGIS“

This is something I would say at an anonymous QGIS user therapy group. I’m willing to attend one of those because being recently and temporally forced to use ArcGIS Desktop again (don’t ask!), I really really really miss QGIS in many ways.

There was a time when I have used ArcGIS on the regular basis. I used it until version 9.3.1 and then decided to move away (toward the light) into QGIS (1.7.4 I think). At that time, I missed some (or even many?) ArcGIS features, but I was willing to accept it in exchange for the freedom of the Open Source philosophy. Since then, a lot have happened in the QGIS world, and I have been watching it closely. I would expect the same have happened in ArcGIS side, but, as far I can see, it didn’t.

I’m using top shelf ArcGIS Desktop Advanced and I’m struggling to do very basic tasks that simply are nonexistent in ArcGIS. So here’s my short list of QGIS functionalities that I’m longing for. For those of you that use ArcGIS exclusively, some of this features may catch you by surprise.

Warning: For those of you that use ArcGIS exclusively, some of this features may catch you by surprise.

Transparency control

“ArcGIS have transparency! It’s in the Display tab, in the layer’s properties dialog!”

Yes, but… you can only set transparency at the layer level. That is, either it’s all transparent, or it’s not…

In QGIS on the other end, you can set transparency at layer level, feature/symbol level, and color level. You can say that this is being overrated, but check the differences in the following images.

Notice that in QGIS you can set transparency at color level everywhere (or almost everywhere) there is a color to select. This includes annotations (like the ones in the image above), labels and composers items. You can even set transparency in colors by using the RGBA function in an expression! How sweet can that be?

Blending modes

This is one of QGIS’s pristine jewels. The ability to combine layers the way you would do in almost any design/photo editing software. At layer or at feature level, you can control how they will “interact” with other layers or features below. Besides the normal mode, QGIS offers 12 other blending modes:  Lighten, Screen, Dodge, Darken, Multiply, Burn, Overlay, Soft light, Hard light, Difference, and Subtract. Check this page to know more about the math behind each one and this image for some examples

It’s not easy to grasp how can this be of any use for cartography before you try it yourself. I had the chance to play around while trying to answer this question.

A very common application for this functionality is when you want to add shadows to simulate the relief by putting a hill shade on top of other layers. In ArcGIS, you can only control the layer transparency, and the result is always a bit pale. But in QGIS, you can keep the strength of the original colors by using the multiply mode in the hill shade layer.

You can also use blending modes in the print composer items, allowing you to combine them with other items and textures. This gives you the opportunity to make more “artistic” things without the need to go post-processing in a design software.

Colour Picker Menu

Controlling color is a very important deal for a cartographer and QGIS allow you to control it like the professional you are. You can select your colours using many different interfaces. Interfaces that you might recognize from software like Inkscape, Photoshop, Gimp and others alike.

My favorite one is the color picker. Using color picker, you can pick colors from anywhere on your screen, either from QGIS itself or outside. This is quite handy and productive when you are trying to use a color from your map, it’s legend, a COLOURlovers palette or a company logo.

You can also copy/paste colors between dialogs, save and import color palettes, and you can even name a color and use it in a variable. With all this available for free, it’s hard to swallow Windows color selector :(.

Vector symbols renderers “powertools”

In ArcGIS, you have a few fancy ways to symbol your vector layers. You got: Single symbol, Unique values, Unique values many fields… and so on. At the first glance, you may think that QGIS lacks some of them. Believe me, it doesn’t! In fact, QGIS offers much more flexibility when you need to symbol your layers.

For starters, it allows you to use fields or expressions on any of the symbols renderers, while ArcGIS only allows the use of fields. Powered by hundreds of functions and the ability to create your owns in python, what you can do with the expression builder has no limits. This means, for instance, that you can combine, select, recalculate, normalize an infinite number of fields to create your own “values” (not to mention that you can tweak your values labels, making it ideal to create the legend).

And then, in QGIS, you have the special (and kinda very specific) renderers, that make you say “wooooh”. Like the Inverted polygons that allow you to fill the the outside of polygons (nice to mask other features), the Point displacement to show points that are too close to each others, and the Heatmap that will transform, ON-THE-FLY, all your points in a layer into a nice heatmap without the need to convert them to raster (and that will update as soon as you, or anyone else, edits the point features).

But I have left the best to the end. The “One rendered to Rule them all”, the Rule-based symbols. With the rule-based renderer, you can add several rules, group them in a tree structure, and set each one with a desired symbol. This gives QGIS users full control of their layer’s symbols, and, paired with expression builder and data-defined properties, opens the door to many wonderful applications.

Atlas

One of my favorite (and missed) features in QGIS is the Map Composer’s Atlas. I know that ArcGIS has its own “Atlas”, the Data Driven Pages, but frankly, it’s simply not the same.

I believe you know the basic functionally that both software allow. You create a map layout and choose a vector layer as coverage, and it will create an output panned or zoomed for each of the layer’s feature. You can also add some labels that will change according to the layers attributes.

But in QGIS, things go a little bit further…

Basically, you can use coverage layer’s attributes and geometry anywhere you can use an expression. And, in QGIS, expressions are everywhere. That way, most layers and map composer items properties can be controlled by a single coverage layer.

With the right configuration, while iterating over the atlas coverage features, you can,  choose what feature to show and what features to hide, change a theme color for your map, rotate and resize your page acording to the feature size, choose a specific logo to came along with your map, and much more. Once again, the sky is the limit.

So, if you pair Atlas it with QGIS data-defined properties, rule-based symbols and expressions, ArcGIS Data Driven Pages are no match. You don’t think so? Try to answer this question then.

Tip: If you really want to leverage your map production, using Spatialite or Postgis databases you can create the perfect atlas coverage layers from views that fit your needs. No data redundancy and they are always updated.

Label and Style dialogs

This one is more of a User Experience thing than an actual feature, but you won’t imagine how refreshing it is to have all Style and Labels options in two single dialogs (with several tabs, of course).

Using the symbol menu in ArcGIS makes me feel like if I’m in the Inception movie, at some point in time, I no longer know where the hell am I. For example, to apply a dashed outline in a fill symbol I needed to open 5 different dialogs, and then go back clicking OK, OK, OK, OK …

In QGIS, once in the properties menu, every setting is (almost) one click way. And you just need to press OK (or Apply ) once to see the result!

As an extra, you can copy/paste styles from one layer to another, making styling several layers even faster. And now you say:

“Don’t be silly! In ArcGIS you can import symbols from other layers too.”

Symbols? yes. Labels? No! And if you had lots of work setting your fancy labels, having to do the exact same/similar thing in another layer, it will make you wanna cry… I did.

(I think I will leave the multiple styles per layer vs data frames comparison for another time)

WFS

“Say what?!!”

Yup, that’s it, ArcGIS Desktop lacks support for WFS OGC standard unless you buy an extra extension: The Data Interoperability Extention.

In a GIS world that, more and more, is evolving towards Open Data, Open Standards and OGC Web Services, this reveals a very mercantile approach by ESRI. If I were an ESRI customer, I would feel outraged. <sarcasm>Or maybe not… maybe I would thank the opportunity to yet invest some more money in it’s really advanced features…<\sarcasm>

In QGIS, like everything else, WFS is absolutely free (as in freedom, not free beer). All you need to do is add the WFS server’s URL, and you can add all the layers you want, with the absolute sure that they are as updated as you can get.

Fortunately for ArcGIS users with a low budget, they can easily make a request for a layer using the internet browser :-P.

http://giswebservices.massgis.state.ma.us/geoserver/wfs?request=GetFeature&service=wfs&version=1.0.0&typename=massgis:GISDATA.TOWNS_POLY&outputformat=SHAPE-ZIP

Or they can simply use QGIS to download it. But, in both cases, be aware that the layers won’t update themselves by magic.

Expression builder

I have already mentioned the use of expressions several times, but for those of you that do not know the expression Builder, I though I end my post with one of my all time favourite features in QGIS.

I do not know enough of ArcGIS expression builder to really criticize it. But, AFAIK, you can use it to create labels and to populate a field using the field calculator. I know that there are many functions that you can use (I have used just a few) but they are not visible to the common user (you probably need to consult the ArcGIS Desktop Help to know them all). And you can create your own functions in VBScript, Python, and JsScript.

On QGIS side, like I said before, the Expression Builder can be used almost everywhere, and this makes it very convenient for many different purposes. In terms of functions, you have hundreds of functions right there in the builder’s dialog, with the corresponding syntax help, and some examples. You also have the fields and values like in ArcGIS, and you even have a “recent expressions” group for re-using recent expressions with no the need to remember prior expression.

Besides, you can create your own functions using Python (no VBScript or JsScript). For this purpose, you have a separate tab with a function editor. The editor have code highlighting and save your functions in your user area, making it available for later use (even for other QGIS sessions).

Conclusion

These are certainly not the only QGIS features that I miss, and they are probably not the most limiting ones (for instance, not being able to fully work with Spatialite and Postgis databases will make, for sure, my life miserable in the near future), but they were the ones I noticed right away when I (re)open ArcGIS for the first time.

I also feel that, based on the QGIS current development momentum, with each QGIS Changelog, the list will grow very fast. And although I haven’t tested ArcGIS Pro, I don’t think ESRI will be able to keep the pace.

“Are there things I still miss from ArcGIS?” Sure. I miss CMYK color support while exporting maps, for instance. But not as much as I miss QGIS now. Besides, I know that those will be addressed sooner or later.

In the end, I kinda enjoyed the opportunity to go back to ArcGIS, as it reinforced the way I think about QGIS. It’s all about freedom! Not only the freedom to use the software (that I was already aware) but also the freedom to control software itself and it’s outputs. Maintaining the users friendliness for new users, a lot have been done to make power users life easier, and they feel very pleased with it (at least I am).

All this being said, the winner is… QGIS!!

The End

(of a very biased post)

EN | PT

With the release of the first long term release (2.8 LTR), and two other stable versions (2.10 and 2.12), 2015 was a great (and busy) year for the QGIS community, with lots of improvements and new features landing on QGIS source code.

As a balance, I have asked users to choose wich were their favorite new features during 2015 (from the visual changelogs list). As a result I got the following Top 5 features list.

5 – Python console improvements (2.8)

Since QGIS 2.8, we can drag and drop python scripts into QGIS window and they will be executed automatically. There is also a new a toolbar icon in the plugins toolbar and a shortcut ( Ctrl-Alt-P) for quick access to the python console.

4 – Processing new algorithms (2.8)

Also in QGIS 2.8, there were introduced some new algorithms to the processing framework. If you are into spatial analysis this must have done your day (or year).

• Regular points algorithm
• Symmetrical difference algorithm
• Vector split algorithm
• Vector grid algorithm
• Hypsometric curves calculation algorithm
• Split lines with lines
• Refactor fields attributes manipulation algorithm

3 – Show rule-based renderer’s legend as a tree (2.8)

There were introduced a few nice improvements to QGIS legend. Version 2.8 brought us a tree presentation for the rule-based renderer. Better still, each node in the tree can be toggled on/off individually providing for great flexibility in which sublayers get rendered in your map.

2 – Advanced digitizing tools (2.8)

If you ever wished you could digitize lines exactly parallel or at right angles, lock lines to specific angles and so on in QGIS? Since QGIS 2.8 you can! The advanced digitizing tools are a port of the CADinput plugin and adds a new panel to QGIS. The panel becomes active when capturing new geometries or geometry parts.

1 – Rule-based labeling (2.12)

This was a very awaited feature (at least by me), and it was voted by the majority of users. Since 2.12, you can style features labels using rules. This gives us even more control over placement and styling of labels. Just like the rule based cartographic rendering, label rules can be nested to allow for extremely flexible styling options. For example, you can render labels differently based on the size of the feature they will be rendered into (as illustrated in the screenshot).

There were other new features that also made the delight of many users. For example, the Improved/consistent projection selection (2.8), PostGIS provider improvements (2.12), Geometry Checker and Geometry Snapper plugins (2.12), and Multiple styles per layer (2.8).

Don’t agree with this list? You can still cast your votes. You can also check the complete results in here.

Obviously, this list means nothing at all. I was a mere exercise as with such a diverse QGIS crowd it would be impossible to build a list that would fit us all. Besides, there were many great enhancements, introduced during 2015, that might have fallen under the radar for most users. Check the visual changelogs for a full list of new features.

On my behalf, to all developers, sponsors and general QGIS contributors,

THANK YOU VERY MUCH FOR YOUR TREMENDOUS WORK!

I wish you a fantastic (and productive) 2016.

EN | PT

Today I needed to create a view in PostGIS that returned the vertexes of a multi-polygon layer. Besides, I needed that they were numerically ordered starting in 1, and with the respective XY coordinates.

It seemed to be a trivial task – all I would need was to use the ST_DumpPoints() function to get all vertexes – if it wasn’t for the fact that PostGIS polygons have a duplicate vertex (the last vertex must be equal to the first one) that I have no interess in showing.

After some try-and-fail, I came up with the following query:

CREATE OR REPLACE VIEW public.my_polygons_vertexes AS
WITH t AS -- Transfor polygons in sets of points
    (SELECT id_polygon,
            st_dumppoints(geom) AS dump
     FROM public.my_polygons),
f AS -- Get the geometry and the indexes from the sets of points 
    (SELECT t.id_polygon,
           (t.dump).path[1] AS part,
           (t.dump).path[3] AS vertex,
           (t.dump).geom AS geom
     FROM t)
-- Get all points filtering the last point for each geometry part
SELECT row_number() OVER () AS gid, -- Creating a unique id
       f.id_polygon,
       f.part,
       f.vertex,
       ST_X(f.geom) as x, -- Get point's X coordinate
       ST_Y(f.geom) as y, -- Get point's Y coordinate
       f.geom::geometry('POINT',4326) as geom -- make sure of the resulting geometry type
FROM f 
WHERE (f.id_polygon, f.part, f.vertex) NOT IN
      (SELECT f.id_polygon,
              f.part,
              max(f.vertex) AS max
       FROM f
       GROUP BY f.id_polygon,
                f.part);

The interesting part occurs in the WHERE clause, basically, from the list of all vertexes, only the ones not included in the list of vertexes with the maximum index by polygon part are showed, that is, the last vertex of each polygon part.

Here’s the result:

The advantage of this approach (using PostGIS) instead of using “Polygons to Lines” and “Lines to points” processing tools is that we just need to change the polygons layer, and save it, to see our vertexes get updated automatically. It’s because of this kind of stuff that I love PostGIS.