# Foreword

In this tutorial, the idea is to verify if render software properly simulate colour mixing. For that, we will use, when possible, IES files in order to mimic as much as possible real phenomena. It extends and refreshes the previous tutorial on the same topic: http://www.keris-studio.fr/blog/?p=5475

Colour mixing refers to Grassmann’s laws (https://en.wikipedia.org/wiki/Grassmann%27s_laws_(color_science)). In colorimetry, Grassmann’s laws govern the superposition of colours. They serve as the foundation for all colorimetric calculations. Hermann Grassmann’s 19th-century studies of human colour perception led him to formulate three laws in his 1853 article « On the Theory of Colour Mixing. » (Grassmann, H. (1853). « Zur Theorie der Farbenmischung »). Continuer la lecture de Light Simulation RGB additive with IES

# Grasshopper, Urban Analysis, 2D Isovist

In this tutorial, the idea is to explore the potential of Isovist for urban analysis. Isovist is the surface or volume of space visible from a specific point. This concept has been proposed by Clifford Tandy in 1967 and then redefined by Michael Benedikt. Isovists are very useful to quantify the perception of urban spaces such as opening, closeness, and also useful to define urban envelopes. Isovists help to with non-intuitive solutions for complex problems.

In this example, we will see how to set up an environment, then use a simple Isovist System, then a more complex one with Ladybug. Then we will see a non-intuitive question: where a very high tower can be seen in a dense urban context.

# Coraulis GeoFun

This is workflow to create a scene in Coraulis. It is done in Blender, but can be realised any similar 3D software. The first step consists in creating a “landscape”. We used the Geometry Nodes to create it, but can be done the usual way or with another software equivalently. It is then lit which can also be done anywhere else. Then the camera is animated along a path. The rendering process uses the Equirectangular 360 Camera which is built in Blender. But we can find the same camera in Cinema 4D, 3DsMax or Twinmotion. The 360 film is then recut to fit Coraulis requirements. Step by step with Blender, C4D or Max, we can create an amazing experience with plying with the context, the movements or the light.