final double roadLength = roadMapping.roadLength();
final Class<? extends RoadMapping> roadMappingClass = roadMapping.getClass();
if (roadMappingClass == RoadMappingU.class) {
final RoadMappingU mappingU = (RoadMappingU) roadMapping;
final double straightLength = mappingU.straightLength();
// draw the first straight
posTheta = roadMapping.startPos(lateralOffset);
from.setLocation(posTheta.x, posTheta.y);
posTheta = roadMapping.map(straightLength, lateralOffset);