Talysis II and Son Lattice are real-time generative software pieces that apply the properties of video signal feedback to simulate recursive functions, typical of a computer algorithm, to build self-similar, symmetrical geometric forms. First shown at ‘Art-ficial Emotion 3.0’ in São Paulo, 2006, Talysis II evokes the geometric work of 60's Op-art movement. Son Lattice, performed at ‘Tomorrow Now’ Venice, 2007 is a sound responsive piece that visualizes sound in real time. Both works are relevant to the field of Art-Maths, not only through recursion, but also because they display properties of symmetry, tessellation and harmonics more commonly associated with computer algorithms and the complex equations of dynamical systems.