# Grasshopper – Parametric Bridge

The objective of this tutorial is to acquire fundamental knowledge of Grasshopper through a simple definition that employs various functions and components. The intention is to construct an entire bridge starting from a single point, which will be converted into lines, surfaces, volumes, and ultimately, a bridge. Since all the stages are parametric, it allows for endless possibilities to generate countless variations.

# Bridge Length

The bridge will need 3 points, one to start, one to end, this will be the length of the bridge, and in between a point to design the curvature of the bridge. This point will be on the line drawn by the two others and will be able to move along the line and in height.

Now let’s create the point on the line

We have our 3 points.

# Bridge height

The middle one will be raised create the arch. Then, a curve is created linking first, raised midpoint and last

# Bridge width

The curve is copied horizontally to obtain the bridge width. This is done by moving the curve Y direction.

Add a Loft to create the bridge deck, Nota, the Relay is put to have a better presentation, create a Relay by double clicking on the Wire.

The bridge can have a thickness by extruding the loft surface.

# Railings

Let’s first create the vertical bars that hold the handrail

Finish by transforming lines into solid objects. Here, extruded polygons are used, this is one solution among many. For the handrail, it’s also possible to use a Tube which is easier…but creates more polygons.

# Handrail

Whole definition

The bridge at its first definition is done

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to Follow…inserting Parametric Bridge Into Unity.

# 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

# Easy Retopology

With this tiny tuto, we will compare 4 automatic retopology methods with Meshlab, Instant Meshes, Rhino and 3DsMax 2023. Meshlab and Instant Meshes are Free, Rhino, not too expensive and Max…well…it’s pro software. There are many other solutions, they will be compared later.

For this test, I’ll use the Nefertiti bust which can be found here: https://www.openculture.com/2019/11/download-stunning-3d-scans-of-the-bust-of-nefertiti.html or here https://sketchfab.com/3d-models/nefertiti-c2f7a55a51fa495eb1d284c0fb8fdcee

Remember that Retopology is not simple decimation, it’s really a way to reorganize the mesh to make it work better for further use.

The file is 6.421.620 polygones. Continuer la lecture de Easy Retopology