Parametrichouse: In this video tutorial, I will show how you can use “random” to produce random numbers and use them in your modeling.

first of all we can double-click on the canvas and search for “random”

You can also find the random tool in sets>sequence section.

The best way to give a “range” for the random tool is to give it a construct domain (maths>domain) tool and freely adjust the minimum and the maximum range of the random tool. The “number” indicates how many numbers you need and finally, the “seed” needs a number input. by changing the number the random tool will produce a new set of numbers.


We start this tutorial by producing an arc with the orange arc tool. This tool will produce an arc in the desired plane and with a defined radius and angle. for the angle, you can give a “pi” tool to the input and adjust it between 0 and 2. basically a 2*pi angle is a full turn arc or a circle!

Now we can extrude the arc and have a surface. We extruded the arc in the z-direction to have a simple arched facade.

you can also define three different random sequences for the radius, angle, and height of the arches.

Further, we divide the facade by giving it to an “isotrim” tool. If you combine the isotrim tool with the “divide domain 2” you can divide your surface in u,v direction.


To extrude the panels in the normal direction we have to extract the normals from the “evaluate surface” tool.

You can also count the number of panels with the “list length” tool (sets>list) and give it to the random “number” input.


By multiplying the random number and the normal direction of the panels we can have a random extruded panel facade.

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