Natural virtual worlds

Synthesising terrains that hold together from the shape of a single valley up to an entire planet, and that a designer can still steer. The methods combine erosion and tectonic models, which give landforms their geological plausibility, with sparse authoring primitives, sketches and example-based synthesis, which give back the control a pure simulation takes away. Terrain analysis borrowed from geomorphometry, such as orometry, serves both to drive the synthesis and to measure whether the result is credible.

Water, glaciers, snow, avalanches, debris flows, dunes and erosion, simulated at landscape scale and at interactive rates. The difficulty is keeping a model physically meaningful while running it over an entire catchment or dune field, which rules out direct numerical simulation. These models are designed with geophysicists and geomorphologists, so that what they produce reads as a plausible history of the terrain and not only as a plausible image of it.

Vegetation and ecosystem dynamics at the scale of a forest or a whole landscape, where millions of plants compete for light, water and space. The work is conducted with forest ecologists and plant scientists, and published in their journals as well as in ours: the visual analysis of forest landscape model simulations appeared in Ecography. The aim is realism, so that plant distributions follow the terrain and its history, and authoring, so that an ecologist can explore a scenario rather than only watch it unfold.

Road networks, villages and buildings that sit consistently on a terrain, generated at the scale of a territory rather than a single plot. The same representations serve communities that rarely meet: archaeologists reconstructing pre-classical dwellings from partial excavation data, thermal and urban modellers who need building geometry as input to physical simulation, and hazard specialists coupling the built environment with rockfalls and floods.

Representation, level of detail and interactive rendering of environments too large to be held in memory, bringing terrain, vegetation and built elements together in a single scene. Scale is the constraint that shapes everything else here, since a representation that does not degrade gracefully cannot be explored in real time. The work feeds production, through long-standing collaborations with game studios, as much as scientific communication, where a rendered scene is what makes a simulation legible to a non-specialist.