In this thesis, we address the problem of virtual terrain creation, by proposing several methods, each aimed at a different aspect of the terrain creation process: generation, amplification, and population. The common denominator guiding our work is the focus on interactivity and control, mandatory criteria when designing tools for artists.

In a first part, we present a set of terrain descriptors, useful to analyze and characterize terrains, posing the basis for the development of this thesis contributions. This part covers a broad range of terrain-related topics (local properties, visibility, hydrology, surface networks), and also serves as a relevant introduction to the field of virtual terrain modeling.

In the next chapters, we propose two independent erosion-based methods, respectively addressing the generation and amplification of mountainous terrains. Both of them build upon the Stream Power law from geomorphology, while introducing new interactive control means. The first one targets the generation of large-scale mountainous ranges, introducing a parallel iterative drainage scheme and making use of the uplift parameter to propose expressive control tools. The second one addresses the amplification of meso-scale mountainous terrains through an interactive multi-scale scheme involving three consecutive types of erosion simulation.

Finally, we present a painting-based method to simplify the process of creating masks for assets, based on the pool of descriptors introduced earlier. Using tools and algorithms from metric learning, we compute a parameterized global mask from a small user input painted over the terrain.