1. A method comprising: receiving a plurality of vehicle environment inputs, the inputs comprising a position in two dimensions for each of a plurality of objects located around a vehicle, each object located in one of four quadrants surrounding the vehicle; determining an object risk value for each of the objects by applying a set of rules to each of the objects, at least a plurality of the object risk values being non-zero, indicating the objects pose a risk to the vehicle; aggregating the object risk values in a front quadrant to generate a front quadrant risk value; aggregating the object risk values in a back quadrant to generate a back quadrant risk value; aggregating the object risk values in a left quadrant to generate a left quadrant risk value; aggregating the object risk values in a right quadrant to generate a right quadrant risk value, wherein at least one of the front, back, left, and right quadrant risk values is determined by aggregating at least two of the non-zero object risk values; and controlling a driver assistance system of the vehicle based on the quadrant risks.