Foreword to the Special Section on Smart Tools and Applications in Graphics (STAG 2021)

The Special Section contains extended and revised versions of the best papers presented at the 8th Conference on Smart Tools and Applications in Graphics (STAG 2021), held virtually on October 28–29, 2021. Five papers were selected by appointed members from the Program Committee; extended versions were submitted and further reviewed by external experts. The result is a collection of paper spanning different Visual Computing domains: from vector graphics on surfaces to image vectorization, from 3D geometric modelling of geological data to computation of the geometric kernel of polyhedra, up to lens-based scene exploration of annotated visual data.