My tutorial on grasshopper is about the project I did in the Sitta’s studio this semester winter 2015-2016 with Maëlle. This project would be defined as an interface between a “Research laboratory on artificial and natural mixed lifes in urban territories” and a cultural and relaxing public space. It is a curvated surface between an indoor garden and an outdoor public square.
You can find here a quick presentation of the project : Windoor Garden
There is the final visualisation of this architecture :
The drawing of the surface was done on Rhino, precisely, each curvature shaped and designed. On the first picture (img 2), you can see the shaped surface, on the second one (img 3) are the curvatures and points on the ground (XY plane) which will be used in Grasshopper :
From those elements, we will model the five components of the project (img 4):
– A beam net
– Two kinds of columns shaped with ramifications like trees
– Pedestrian paths on the upper face of our surface
– An interior walkway
– Two zones of envelope
Here are the files I did :
The main Rhinoceros 3D file : WindoorGarden3dm
The main Grasshopper file : WindoorGardenGh
And bellow each part of this tutorial, I put a simplified grasshopper file which work with the main Rhino file.
1 • THE BEAM NET
We are going to create a grid of lines on the XY plane. Those lines will be projected on our surface and then turned into beams thanks to extrusions.
1.1. To create the grid, I first setted one point (img 5, 1) from which I did a serie of lines parallel to the X-axe and a serie parallel to the Y-axe. Length and numbers of lines are vaguely defined (img 5, 2), just enough to cover the whole surface of the project.
1.2. The two red curves on the picture above (img 6) are the delimited area of our beams. The first one, the biggest, is called the WinterGarden and the second one, the smallest, is the Forest. I built a brep volume from those curves (boundary surface and Z extrusion (img 7, 1)) that helped me to cut out the lines with the cluster “trim with brep”(img 7, 2). I kept lines which were inside the brep volume, coming from the “ci” output. There are now four types of lines, in their reciprocal clusters :
X-axed lines of the winter garden
Y-axed lines of the winter garden
X-axed lines of the forest
Y-axed lines of the forest
1.3. I projected all thoses lines along the z-axe on the surface (img 7, 3).
But this surface is complicated. In Rhino, it is a polysurface composed of 18 surfaces. To make the projection working, I had to explode the polysurface into its components, I used “deconstruct brep” and its “F” output. To make the projection work simultaneously on each surface, I had to graft them in a data tree.(img 7, 4). There is now 18 branches with one surface in each.
See here the result (img 8) :
Some part of the polysurface are below the XY plane, so some parts of curves are too (img 8, 1). To delete them, I used again “Trim with brep” (img 8, 2). I built Breps exactly the same way than before but I extruded them only under the XY plane. (img 8, 3). This time I used curves coming from the output “co”, outside the brep volume.
1.4. For the extrusion of beams, I did like following : [‘]. The apostrophe is the curve, hooks are the beam. I extruded to the bottom in Z axe and I extruded on both sides in X or Y direction. So, I merged together X-curves and Y-curves (img 9, 1), I extruded all of them along the Z axe, with a negative number. (img 9, 2). Then I extrude X-curves along the Y axe and Y-curves along the X axe. The parametric value is the thickness of the beam so I divided it by 2 to extrude half positively and half negatively (img 9, 3)
1.5. The beam net is done.
WindoorGardenGh_beams
2 • COLUMNS
2.1. There is two kind of columns according to their height. The smallest are composed with one trunk and three branches. The biggest are composed with one trunk, three branches giving each three branches again.
From points determinated in Rhino and their projection on our main surface I draw lines (img 10, 1&2). Those lines are splitted in two groups according to their length (img 10, 3)
2.2. Biggest trees :
I evaluated the lenght of the line at 65% (parametric value) to obtain the line which is the trunk. (img 11, 1). The end points of each trunk line are graft (to deal with all columns at the same time). They are used as the base plan of 3 polar points (2/3, 4/3 and 2Pi)