GLASS: Generator for Large Scale Structure

We present GLASS, the Generator for Large Scale Structure, a new code simulation of galaxy surveys cosmology, which iteratively builds light cone with matter, galaxies, and weak gravitational lensing signals as sequence nested shells. This allows us to create deep realistic simulations at high angular resolution on standard computer hardware low resource consumption. GLASS also introduces technique generate transformations Gaussian random fields (including lognormal) essentially arbitrary precision, an iterative line-of-sight integration over matter shells obtain fields, flexible modelling galaxies sector. demonstrate that readily produces simulated data sets per cent-level accurate two-point statistics clustering lensing, thus enabling simulation-based validation inference is limited only by our current knowledge input properties.