Deriving Roof Pitch and Azimuth from Drone Point Clouds Using Python

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A drone survey of a roof produces a point cloud of millions of 3D points describing the surface. For solar and roofing work, the key figures are each roof plane's steepness, its facing direction, and its surface area. The approach described uses Python with techniques such as SVD, RANSAC plane fitting, and basic trigonometry to convert raw points into these measurements. The author suggests testing the method on real scans, comparing results against hand measurements, and adjusting thresholds to match the physical roof. Readers are invited to extend the work, for instance with alpha-shape area calculations or obstruction detection.

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