AA-1 (Angel Algorithm-1)
Line-to-Line Circular Turn Algorithm
AA-1 is a computational geometry algorithm for generating a circular turning path from two directional lines. It calculates line intersection, tangent length, azimuths, intersection angle, turning direction, radius of curvature, arc center, and intermediate arc-point coordinates.
The original 2007 direction-determination logic is preserved for historical reference. The 2026 implementation includes normalized angular-difference handling, EPSILON-based comparisons, and safeguards for boundary and invalid-input cases.