Dynamic Real-Time Fire Propagation for Networked Multiplayer Games

Simulating fire propagation in games can be problematic since it requires immense computational power if the fire is portrayed physically accurate. To decrease the computational power required, simplifications and approximations must be made. The aim of this thesis is to evaluate possible methods for simulating fire spread in a networked game environment. More specifically, a level set and a node graph method are implemented and investigated. A vector field was created with the different level properties, which the two methods used as a base for the fire behavior. The performance and overall behavior of the methods were evaluated and tested in order to create an optimized simulation suited for games. Two implementations were made in the Frostbite game engine. The level set propagates the fire with two different level set operators; the normal advection operator and the vector field operator. The normal advection operator spreads the fire outwards in the normal direction. The vector field operator spreads the fire front according to the vector field. The node graph implementation uses a semi-connected bi-directed graph with nodes as starting positions for the fire. The fire spreads through the nodes via their connections. This implementation also depends on the vector field which was translated to the nodes through scalar projection. The vector field represents the properties of fire dynamics and can be adjusted to move the level set and node graph implementation according to wind, slope and fuel. The node graph implementation was further developed with networked capabilities, a heat grid which translates the heat of the node graph making it possible to sample the heat at a position within the level, and also basic interaction with vegetation.
Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet