VI-Suite v0.6 – Basic Radiance Simulation


Cutaway of a saw-tooth roof and lux simulation


I have now uploaded a video tutorial covering the basics of Radiance simulation with the LiVi component of the VI-Suite. The video concentrates on the options within the relevant nodes and the Radiance material options. One thing I should probably reiterate is that a single Blender object can have more than one Radiance material attached as Blender allows you to associated materials with each individual face. The example below shows a red glass sphere with some blue plastic faces.

Radiance materials

Radiance per face materials


Also a version from today or later should be used to correspond completely with the options I talk about.

Otherwise I think the video mentions everything else I wanted to say and, as ever, can be viewed below.


VI-Suite v0.6 – Sky View Factor & Shadow Mapping

SVF calculation

Sky View Factor calculation

I’ve just uploaded a video that introduces the Sky View Factor (SVF) and shadow mapping capabilities of the VI-Suite.

The video also introduces the vi-suite-log file and how it can be used to provide data for some simple custom results processing.

As always I forgot some things in the video. The main thing is that coloured results geometry are placed in their own Blender collection called ‘LiVi Results’ although this video does not cover ‘LiVi’ analysis, but sky view and shadow are lighting related so I place these results within this collection. Once the VI-Suite has created this collection it is important to remember not to put your own geometry in it, as this geometry may then be ignored in subsequent analyses.

Results objects in this collection will be replaced every time a simulation is done, so if you want to keep this geometry for comparative analysis between scenarios move the object out of the ‘LiVi Results’ collection into the scene collection or your own collection.

I’ll also mention that clicking on the heat map analysis itself will bring up a matplotlib display window where you can set some options for the heat map and save that heatmap out to an image.

And finally, the ‘Results out’ sockets of the SVF and shadow mapping nodes can be connected to a VI Chart node for graphing, or the VI CSV node for outputting csv formatted results, but I will cover these two nodes in a separate video.

And finally, finally a github zip download from today or later is required to get the days reported in the VI-Suite log file.

And finally, finally, finally if in solid shading mode I suggest you choose ‘Flat’ shading, which can be found in the ‘Shading’ menu at the top right of the 3D viewport, for the best results visualisation.

I think that’s everything I’ve forgotten. Video is linked below.

VI-Suite v0.6 – Sun Path

I’ve just uploaded a video tutorial for sun path and simple shadowing analysis in v0.6.

The video covers sun path creation and the features of Blender’s viewport shading for single and multiple sun shadow creation.

There’s a couple of things I forgot to mention in the video. One is that when creating a new sun path you’ll notice that a new collection is created called ‘SunPath’ and the sun path object is placed within it. As mentioned in the previous video you should avoid putting your own geometry into this collection. Another is that the colours of the sun path base can also be altered with the material properties associated with the sun path base object.

And one final thing. The time used for the sun position is local solar time, not clock time. Any local daytime saving, or time zone adjustment, should be factored in by the user.

Link to the video is below and to those who celebrate it I wish you a very Merry Christmas.


VI-Suite v0.6 – Update 3

Dear all.

I have, I believe, finished adding features to the VI-Suite, for now, and I am now moving into bug-fixing mode. I do not have the access to other computing platforms that I used to have due to the pandemic, so I am interested to hear if there are any activation issues with v0.6 on OS X, Windows and different flavours of Linux.

The zip file of the source code can be downloaded from This zip file should be installable directly from Blender’s addon preferences window. I have been working purely with Blender 2.83.6 LTS, and while it may work on later Blender versions I am primarily interested in any activation issues with 2.83.6 LTS.

I have not yet finished updating the user manual for v0.6 but for simple sun path, shadow mapping, SVF and LiVi (Radiance) calculations the process is quite similar to v0.4 and the tutorial videos for that release will hopefully give you enough to get started. EnVi (EnergyPlus) and FloVi (OpenFOAM) have changed quite a bit, and I advise waiting for updated documentation before trying those components. I will post here again when a basic manual is available. Tutorial videos will follow after that.

Any bug reports should go in the github page and general questions on the google group Please include in any bug report platform information, the nature and version of the Blender install and any relevant terminal output.




VI-Suite v0.6 – Update

Dear all.

As some people have been asking what my plans are regarding a Blender 2.8 version of the VI-Suite, I thought I would post an update.

The eagle-eyed amongst you may have noticed that the title of this post skips a version. v0.5 was going to be the last VI-Suite version of the 2.7 series but as 2.8 is now out I decided to roll those changes in to v0.6.

Over the last couple of weeks sun path, wind rose, shadow maps, sky view factor and LiVi have all been, at least in part, transfered over. I am in the process of tranferring EnVi over. There are many bugs remaining, and I would not say v0.6 is ready for usage, but good progress is being made. I’m hopeful that early next year an initial release might be ready.

Once things have stabilised a bit I will post the link to the github repository here.



Blender 2.8 - LiVi

LiVi in Blender 2.80


VI-Suite v0.4 – Publication

An article describing the VI-Suite has been published in ‘Open Geospatial Data, Software and Standards’. As the article is open-access, the full text can be accessed from The article was co-authored with Filip Biljecki from TU Delft/National University of Singapore and examines the VI-Suite from a geospatial data perspective.

Southall, R., Biljecki, F.
The VI-Suite: a set of environmental analysis tools with geospatial data applications
Open Geospatial Data, Software and Standards 2(1), Sep 2017, 23
Abstract: The VI-Suite is a free and open-source addon for the 3D content creation application Blender, developed primarily as a tool for the contextual and performative analysis of buildings. Its functionality has grown from simple, static lighting analysis to fully parametric lighting, shadowing, and building energy analyses. It adopts a flexible, mesh geometry based approach to the specification of calculation points and this has made it suitable for certain types of 3D geospatial analyses and data visualisation.


As this is the first paper that describes the VI-Suite the article can be used to cite the VI-Suite. The bibtext formatted citation can be downloaded here.

An image from the paper is shown below.


Annual irradiance on a building facade

VI-Suite v0.4 – Artificial Lighting Simulation

Lighting simulation of Blender's classroom scene

Radiance visual and falsecolour rendering of Blender’s classroom scene

The VI-Suite can simulate artificial as well as natural lighting. Three main methods are available:

  • Specifying a Radiance light material to mesh elements.
  • Associating an IES file with a Blender lamp.
  • Associating an IES file with a Blender mesh plane to create an array of lights.

IES files, which are text files describing the brightness of a lamp or luminaire from different viewing angles, are released by manufacturers for their specific lighting products and can usually be downloaded from their websites. This gives the opportunity to see how real world products will illuminate a scene visually and with the VI-Suite numerically.

As ever, the video below describes these three methods.