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--- transportation:roads [2026/04/18 23:59] – timb
+++ transportation:roads [2026/04/19 00:00] (current) – [Science] timb
@@ Line 76: / Line 76: @@
 [[https://www.theguardian.com/science/2025/feb/03/farewell-potholes-uk-team-invents-self-healing-road-surface|https://www.theguardian.com/science/2025/feb/03/farewell-potholes-uk-team-invents-self-healing-road-surface]]
+===== Science =====
+== The Simple Geometry Behind Any Road ==
+April 13, 2026 - "SANDBOX SPIRIT"
+In the last blog post, I explained what sits at the backbone of procedurally generated roads: the data structure, aka the minimum information you need to describe any piece of road infrastructure. The answer to that fundamental question was a set of abstract cross-sections of the road, each storing a snapshot of how the road looks at that specific point (or, should I say, line). I called them simply: profiles.
+A good analogy I didn’t have the inspiration to make at the moment was to compare them with Bezier splines. To store a Bezier spline, you don’t need to save the entire curve explicitly, but just anchor points and handle positions. With a bit of math and a few formulas, you can reconstruct the actual path at any time by interpolating between the control points.
+The profile-based representation works the same in my system. The profiles are the control information, and the actual geometry defining the road path is the interpolated result of those profiles.
+In this blog post, I’ll go over how I am computing the purple part. How to interpolate between these green profiles to generate beautifully smooth, parallel paths?
+https://sandboxspirit.com/blog/simple-geometry-of-roads/