CS Seminari: Simulation and modeling of realistic 3D forest scenes (Oscar Argudo Medrano, UPC)

The generation of truly believable simulated natural environments remains an unsolved problem in computer graphics. Realistic virtual forests are a central component of computer-generated environments in games, film, and simulation, yet current approaches often fail to capture the visual richness of real ecosystems. A key limitation is that achieving realism requires more than static modeling focused on placing trees of the right species and size; it emerges from a long sequence of growth, disturbance, and decay processes. In real forests, events such as fire, wind, pests, competition, and senescence leave lasting and visually salient traces that convey the history and structure of the ecosystem.

In this talk, I will present a framework for the simulation and modeling of realistic 3D forest scenes that explicitly incorporates life history, disturbance events, and death and decay. The approach decouples ecosystem simulation from geometric realization, allowing forests with millions of trees to be generated efficiently while preserving visual diversity and plausibility. The pipeline proceeds in three stages: (1) simulation of individual tree growth under varying environmental conditions to sample feasible plant forms and derive scaling relationships; (2) an individual-based ecosystem simulation that models competition, disturbance, and decay over time; and (3) a model quantization and instantiation step that selects and places representative geometric models consistent with each tree’s simulated history. Beyond computer graphics, this work illustrates how combining long-term simulation with deferred model realization enables scalable, history-aware synthesis of complex ecosystems spanning millions of plants and several square kilometers.