collisionBoxes = new ArrayList<>(EnumFacing.values().length);
        List<CollisionBox> boxes = new ArrayList<>();

        for (int i = 0; i < EnumFacing.values().length; i++) {
            collisionBoxes.add(null);
        }

// more stuff here initializing "boxes"

        for (EnumFacing dir : new EnumFacing[]{EnumFacing.NORTH, EnumFacing.EAST, EnumFacing.SOUTH, EnumFacing.WEST}) {

            List<CollisionBox> turnedBoxes = new ArrayList<>();

            for (CollisionBox rawBox : boxes) {
                CollisionBox turnedBox = rawBox.copy();
                turnedBox.apply(matrix);
                turnedBoxes.add(turnedBox);
            }

            collisionBoxes.set(dir.getIndex(), turnedBoxes);

            matrix.translate(new Vector3(0.5, 0.5, 0.5)).rotate(-q, new Vector3(0, 1, 0)).translate(new Vector3(-0.5, -0.5, -0.5));
        }