VI-Suite v0.2 – Tutorial 1 – Installation

Hi.

Embedded below is the first video in the v0.2 tutorial series. In it I quickly go over the installation of the VI-Suite and navigating the Blender interface to get you starting to create VI-Suite nodes.

v0.2 is mostly a bug fix release with some under the hood changes that hopefully make it more robust. The most important of these is in LiVi where results are now stored within the sensing meshes and results animated in a different way so there is no longer an 8 frame animation limit. The wind rose and sun path analyses have also seen some cosmetic love and there is one new feature; the ASC import node for importing accurate terrain height data in Esri Ascii format.

v0.2 has been released onto the VI-Suite website at http://arts.brighton.ac.uk/projects/vi-suite. As Google Code is shutting down VI-Suite code repositories can now be found on GitHub. v0.2 code can be checked out from https://github.com/rgsouthall/vi-suite.v02.git and v0.3 code, which is currently bleeding edge and unlikely to run, can be found at https://github.com/rgsouthall/vi-suite.v03.git.

VI-Suite v0.2 Installation from Ryan Southall on Vimeo.

Repository split

Today I split the VI-Suite Google Code repository to create a v01 branch as I prepare for the v0.1 beta release. The v01 branch will now receive bug fixes only. New feature development will continue  in the default branch. A momentous day. For me at least.

To checkout from the new v0.1 branch with Mercurial the following command should do it

hg clone https://RGSouthall@code.google.com/p/vi-suite.v01/

Remember to change the name of the directory created from vi-suite.v01 to vi-suite.

For the development branch

hg clone https://RGSouthall@code.google.com/p/vi-suite/

LiVi Climate Based Daylight Modelling

Climate Based Daylight Modelling (CBDM) is achieved with the LiVi CBDM node. CBDM takes hourly sky data, in this case from an EPW weather file selected in a VI Location node, and calculates lighting metrics either cumulative;y for the period simulated, or for each hour. CBDM offers greater contextualisation compared to a daylight factor calculation, and greater confidence compared to static time based simulations. A typical node set-up for a LiVi CBDM analysis is shown below.
livicbdmnode
CBDM analysis for the calculation of advanced lighting metrics such as light exposure (luxhours), radiation exposure (kWh/m²), daylight availability (%), hourly radiation (W), and useful daylight illuminance (%).

A short video showing a CBDM analysis can be watched below.

VI-Suite Climate Based Daylight Modelling from Ryan Southall on Vimeo.

LiVi Compliance Analysis

A LiVi Compliance analysis checks the calculated lighting performance against some common lighting standards. Standards implemented so far are the Building Research Establishments Environmental Assessment Method (BREEAM) and the Code for Sustainable Homes. The process of doing a compliance analysis is very similar to a Basic LiVi analysis, but requires a LiVi Compliance node instead of a LiVi Basic node. Typical node layout is shown below.
livicompnode

The main difference compared to a basic LiVi analysis is during results visualisation where a compliance panel can be overlaid onto Blender’s 3D view. This compliance panel shows details about the target metrics required to gain compliance, the actual metrics calculated for the space and gives an estimate of overall compliance and credits gained based on the spaces simulated.
A short video showing the process of doing a compliance analysis can be watched below.

VI-Suite LiVi Complaince analysis from Ryan Southall on Vimeo.

Basic LiVi Analysis

LiVi is the component of the VI-Suite that acts as a pre/post-processor for the Radiance lighting simulation suite. An installation of Radiance is therefore required. Radiance installers for Windows, OS X and Linux can be found at https://openstudio.nrel.gov/getting-started-developer/getting-started-radiance (registration required). In addition on Linux Radiance may be available to install through the distribution’s package management system. LiVi assumes that the Radiance installation is situated in the following locations:

  • Windows – C:\Program Files (x86)\Radiance (64bit system) or C:\Program Files\Radiance (32bit system)
  • OS X – /usr/local/radiance
  • Linux – /usr/share/radiance or /usr/local/radiance

Radiance is a very advanced set of lighting simulation tools that permit the calculation of almost any lighting metric. A basic LiVi analysis can calculate illuminanace, irradiance and daylight factors. In addition, using the evalglare package included with the VI-Suite, glare can be predicted.

A basic LiVi analysis requires a minimum of three nodes: LiVi Geometry, LiVi Basic, and LiVi Simulation. A VI Location node may also be required. A typical node set-up is shown below.

livibasnode

LiVi Geometry exports Blender geometry and materiality to Radiance format, LiVi Basic creates a basic sky context, and LiVi Simulation runs the Radiance simulation. Display of the results is controlled from the VI Display tab in the 3D view properties panel.
A short video showing the set-up of a basic LiVi analysis can be watched below.

VI-Suite Basic LiVi analysis from Ryan Southall on Vimeo.

Compiling Blender to Increase Vertex Colour Layers

Blender usually comes with a limit of 8 vertex colour layers that can be applied to an object. As the VI-Suite uses vertex colour layers to visualise results this means that, in effect, only 8 steps of an animation can be visualised. To increase the permitted number vertex colour layers some changes are required to the Blender source code, and then Blender must be compiled. The Blender source code can be downloaded from http://www.blender.org/download/. In side the source archive file is a directory called source. Relative to this source directory the source code changes required to the 2.69 version are as follows:

  • Line 182 in the file source/blender/makesdna/DNA_customdata_types.h should be changed from ‘#define MAX_MCOL    8’ to  ‘#define MAX_MCOL   256’ or however many vertex colour layers you want. I have tested up to 256.
  • Line 143 in source/blender/render/extern/include/RE_shader_ext.h should be changed from ‘ShadeInputCol col[8];’ to ‘ShadeInputCol col[256];’

Instructions for compiling Blender for different platforms can be found here http://wiki.blender.org/index.php/Dev:Doc/Building_Blender

Shadow Study node

The Vi-Suite Shadow Study node uses an in-built function of Blender to check whether faces of the Blender geometry can see the sun at each time step of the simulation period. The Shadow Study node then composites these results to determine what proportion of time a face is in shade. A typical node set-up is shown in figure below.

ssnode1

And the video below shows the Shadow Study node in operation.

VI-Suite Shadow Study Node from Ryan Southall on Vimeo.