projection.js

var origin = entities[0].position;
for (var i = 0; i < entities.length; i++) {
    var entity = entities[i];
    entity.relativePosition.copyFrom(entity.position).subThis(origin);
    entity.distance = entity.relativePosition.distance();
    entity.direction = Math.atan2(entity.relativePosition.y, entity.relativePosition.x);
    entity.distortion = res*Math.atan2(entity.distance, elevation)/Math.PI;
    entity.projection.x = Math.cos(entity.direction) * entity.distortion;
    entity.projection.y = Math.sin(entity.direction) * entity.distortion;
    drawVessel(entity.projection.x, entity.projection.y, entity.orientation);
}