QGIS 2.5D Functionality

I originally posted this on xyHt on 16th Feb 2016

 

I had, when I went into the office today, to do an amazing blog about the QGIS 2.5D functionality and how it was the beginning of QGIS’ journey into the 3rd dimension.

Only I can’t, Anita Graser, the author of “Learning QGIS 2.0” and owner of the “Free and open source ramblings” blog beat me to it. I was not only beaten but she went and added a temporal element to it all….I can’t be upset, I have a lot of time and respect for Anita. In this case it worked in my favour, my competitiveness came out and I sat and thought of just how I was going to do something better.

First let’s discuss the “2.5” functionality, why haven’t you seen it & why is it gaining publicity?

The 2.5D rendering is a new function added to the styling options in QGIS 2.14 which will be released [approx] 25th March. This is available now, primarily for testing purposes through the QGIS 2.13 development release on OSGEO, so what you are reading might change further before release.

Last year Matthias Kuhn set up a crowdfunding campaign to provide oblique 3D rendering as an option to the QGIS output but most importantly enable a way to print/output the result as many of the plugins available in QGIS are just visualisation tools. Little did Matthias realise how popular this idea was and it was funded by November 30th 2015. 

 

“This project aims to improve the internal possibilities of QGIS to give an oblique view 3D effect based on a height attribute and an angle while fully preserving all the possibilities which the QGIS styling offers. But it doesn’t stop there, the whole rendering is built in a modular way so you can use all of its parts for countless other possibilities.”

 

As stated earlier, it is still in a development test phase but being QGIS it is still very stable….oh yes, it is a fully functional death star. Let’s look at the process for using this function:

Buildings without the 2.5D effect applied
Buildings without the 2.5D effect applied
The standard interface we are all used to
The standard interface we are all used to
A look in the dropdown shows a new function - 2.5D rendering!
A look in the dropdown shows a new function – 2.5D rendering!
New options!
New options!

As you can see, there is a new interface and options when you select the 2.5D option. Height of the “effect” is based on either a field in the attribution or a z (height) geometry. In this case [1] it is based on a field which I had to create based on the geometry called “z_rel” (short for relative z).

Now here is something interesting – I was using 3D data, in fact I was using 3D geospatial shapefiles in ArcGIS filegdb format with roof detail and even windows BUT it wouldn’t work. Not because of anything major but because the plugin only supports simple extrusion, or simple z geometry (meaning no multipatch!). Once the z values for the buildings were extracted to a field and the footprints extracted from the multipatch data, the result was good, as you may see below:

The end result of using 2.5D with the buildings
The end result of using 2.5D with the buildings

We can add a little more detail by using trees. I first tried using the 2.5D render to display the trees and found that it would provide an “extrude effect” down the side of the tree:

You can see the extrude effect on the side of the trees
You can see the extrude effect on the side of the trees
Trying to mask the effect
Trying to mask the effect

 

Final attempt with just shadow on the tree canopies
Final attempt with just shadow on the tree canopies

Above you can see in the 2 images side by side that the trees look too heavy, whereas by taking the tree canopy and applying a simple shadow, it is easy to make the trees come to life. Note that there is no option to remove the extrusion effect or side of the isometric option (referred to as the wall color) – if this was possible I believe a fairly realistic effect could be created as you could base the 2.5D on the height of the canopy and then add another vector data to simulate a trunk (or not if it looks bad).

 

From a cartographic point of view, I think this effect works well and with a little adjustment and refinement we could create some magical maps..my only question is that when we are trying to simulate 3D, why don’t we just draw 3D? After all, using exactly the same data I created the below using QGIS2Threejs, you can play with it yourself here (be warned that due to the amount of data it is a little slow)

Using the same data
Using the same data

One thing is for sure, I will be watching this closely and seeing what develops, I suggest you do the same!

Nick D

Dragon_in_Nature

Trying to provide what they don't realise they need

A month into employ with Elliot and the amazing Garsdale Design Team and I am starting to realise the scale of the task ahead….this is the same as almost every other geospatial expert reading this: You could recreate the Earth with enabled 3D and location intelligence but how do you convince people that it is what they need?

For years I’ve read about Business Intelligence Modelling, Smart Cities, Asset Management, Integrated Solutions and all the other really cool phrases doing the rounds at the moment, I’ve been to countless conferences and talks on these super intelligent solutions but when the dust settles and the cold light of day comes, where are the customers to buy it?

Smart City 1

Having sat around the table with some of the top experts in the industry, one thing becomes clear [this is not a sales pitch but to demonstrate a point], Garsdale Design and I can create ANYTHING, cities so smart you have to put your headphones in to block out the breathing…We were playing around and had a small town built in minutes, then using basic GIS we added full attribution which could be reported PER FLOOR of each building and even used as a basis for further analysis. You want the energy efficiency of each building floor? It’s there, you want the building areas blocked by trees, a mere click away….add in demographic data and there is the potential to even find out what type of newspaper each person on each floor reads.

Like I said, there is nothing that we cannot create given a little time – so why isn’t it mainstream? Surely something so cost effective and mainstream would be selling like hotcakes? You would have thought that the UK Government (Listen up Mr Cameron!) would make this mandatory for Governmental bodies to not only collate the data to a single point but to also make the data more efficient. How many times have we heard that we have to wait while Mr X in one department has to talk to Mrs Y in another department because they “don’t deal” with that specific information….Excuse me, but surely in this day and age, shouldn’t all the data be in one place which everyone has access to? Shouldn’t we be analysing ALL the data rather than a jigsaw with missing pieces which only leads to incomplete answers?

3D GIS Intelligence fig 2

Here is where I think that things have been going wrong – We are rubbish promoters of ourselves. Yup, I just said you were rubbish…..

You, like me, didn’t see the bigger picture until it was too late. We sold the world GIS Server systems and cool shiny web maps but we didn’t sell the whole package….we didn’t sell data management. A lot of you (yes I am assigning a little blame) made a quick buck, sold the server and ran….some TRIED to sell some asset management/ data management but weren’t aware that we were going to get 3D GIS and the ability to integrate all the information into a system which could  join the gaps and churn through it all.

And here is the crux of the problem, we now have the ability to provide smart cities and amazingly clever urban modelling but how do we get people to buy into ANOTHER geospatial fad? What will convince them to take another step?

SmartCity2

We (Garsdale Design Ltd) have a plan….but as a collective we need to start providing more intelligent solutions, stop being lazy with the metadata and do more table joining to make the non-geospatial people realise what they are missing.

 

Dragons8mycat