The low-to-high-density transition in compressed silica glass is investigated using percolation theory. Large-scale molecular dynamics simulations of SiO2 glasses, with system sizes of up to 10^6 atoms and pressures ranging from 0 to 35 GPa, were carried out to investigate the emergence of structural motifs and their growth to system-spanning length scales under compression. On this basis, we introduced long-range descriptors that complement conventional local and medium-range structural measures. The results reveal critical percolation transitions of SiOZ -SiOZ clusters with increasing coordination number Z.The critical exponents of the lowest-pressure transitions, i.e., tetrahedral and pentahedral networks, are consistent with standard percolation predictions, whereas for higher-coordinated polyhedra the data collapse suggests possible deviations that are tentatively associated with a rigidity-percolation mechanism. SiSiz-SiSiz clusters were also analyzed using the non-bonded approach. Bonded and non-bonded approaches complement each other in a particularly illuminating way for describing pressure-induced structural transformations and common mechanisms shared by bonded glasses, such as SiO2, and non-bonded glasses, such as amorphous ice.