Spatial Point Rotation Around Center Using Three Sequential Transformations

Rotating a spatial point P around a center point C can be achieved through three sequential transformations: first translating C to the coordinate system origin, then rotating P around the origin, and finally translating C back to its original position. When image points are multiplied by transformation matrices, resulting positions may not be integers, requiring gray value interpolation. This article presents an improved rotation function imrotate_my that uses modulo operations to handle out-of-bound areas, providing better boundary visualization compared to MATLAB's standard imrotate function which sets such areas to zero.