final FixtureDef fixtureDef = new FixtureDef();
fixtureDef.density = pDensity;
fixtureDef.restitution = pElasticity;
fixtureDef.friction = pFriction;
fixtureDef.isSensor = pSensor;
final Filter filter = fixtureDef.filter;
filter.categoryBits = pCategoryBits;
filter.maskBits = pMaskBits;
filter.groupIndex = pGroupIndex;
return fixtureDef;
}