Rotating Grids and Moiré Patterns

This GeoGebra example demonstrates how rotating a copy of a square grid or line array creates moiré patterns, visual interference, and symmetric motion effects. It involves rotation, affine transformations, vectors, sequences, parameterized animation, and the effect of angular frequency on pattern density. The construction uses Vector to define directions, Rotate to turn points or vectors by parameter t, and Sequence to generate multiple grid elements; objects such as t, N, A, B, v, u, scale, list1, and buttons control angle, count, base points, vectors, scaling, and animation state. It is suitable for middle and high school geometry, transformation geometry, parametric equations, dynamic geometry lessons, and mathematical art visualization.