Hello everyone, i'm new to Houdini and decided to start with a very small idea which i hope wasn't too ambitious. I really tried googling on my own even looking for tutorials but didn't find even an aproximation on how to solve my problem.

Basically what i want to do is create some parametric geometry on the ground that can later be extruded upward into polygons and extruded again into walls. I want that geometry to be composed of parametric shapes like rectangles and circles which get combined into a spline with points which can be referenced later, then the spline gets extruded into a polygon and that polygon gets extruded again so it has thickness. (i have attached a diagram, please excuse my paint skills)

My main issue is that i haven't been able to find a node that does this, combine two curves. From what i've seen the closest to a rectangle would be a grid set to bezier. Still i can't get them to join together with any node. I tried boolean, merge and a couple more.

Again, please excuse me if this is the result of just too much ambition, in my mind it all seems logical and simple enough. if you could at least point me to a wiki article or a guide to follow trough with this i'd be extremely grateful.

The first thing to understand here is that you can create and work with different types of geo in Houdini - Primitives vs polygons / polylines, vs Bezier vs NURBS etc. Many SOP's are intended to work with poly's only. A polygon rectangle is simply a grid set to 2 rows and 2 columns.

Assuming all shapes are polygons and lie on the same plane a boolean set to surface and union will do what you want. Follow it with Divide set to 'Remove shared edges' - or Labs Dissolve Flat Edges. See attached example.

You could generate your wall thickness - before extruding - with 'Polyexpand2D' SOP, followed up with Labs Dissolve Flat Edges.

Hi arqsbo3d,

here are two examples for extruding walls from intersecting curves.