#zhiduo

Hi, thanks for the question!

Zhiduo/直裰 and Daopao/道袍 are indeed very similar, and have even referred to the same thing at times. Both are traditional men’s hanfu popular during the Ming Dynasty, and comprise of a full-length, cross-collar robe with side slits beginning below the waist.

The two are differentiated nowadays by the understanding that Daopao has side panels to conceal the undergarments, while Zhiduo does not, so that the garments underneath are visible.

Here are some pictures for comparison:

- Zhiduo:

- Daopao - notice how there is extra fabric on the sides to conceal the space between the slits:

No no don’t apologize...

Generally speaking, pibo can go on generic Tang and Song styles, although people usually don’t wear a pibo with untucked parallel collar shan, which I think because people who wears these style usually like to put a more “daily” look so pibo was not used, but you can put on pibo if you like. Also historically, I don’t think pibo was fashionable in Song dynasty anyway although they might appeared in some court dresses (usually called 霞帔/Xiápèi). Like I have only seen a handful of paintings and statues with pibo, and these artefacts aren’t really from Song dynasty (the paintings are most likely from the Five Dynasties and Ten Kingdoms period, and the statues, although sculpt in Song dynasty, they are figures of immortals in a temple).

Due to the long history of the term used,  褙子 could means several things... I prefer to called these parallel collar top with full collar 衫shan, because it is a generic term refers to all unlined tops made without a separate waist.  褙子 for me means a couple specific things, as shown as these couple of slides I made last year.

However,  褙子 can also be referred to other things.

Is changgansi beizi perhaps the ‘jacket with 3/4 sleeves’? 黄晟墓褙子 from Southern Song actually only reaches the wrist as well, but it is not as oversized as changgansi beizi and the sleeves usually was a bit flared. 

褙子 is like a jacket so it could stacked on top of other tops or moxiong depending on the weather. Technically speaking there should always be another layer between moxiong and beizi, but whatever. There isn’t a strict rule for it today. 

Proper Song-style cross-collar shan is kinda rare in the market today, especially for woman (because I don’t think any was excavated). Most of the time the “cross-collars” are parallel-collar shan. 

Some types of generic woman cross-collar shan.

Below are a couple of examples of men wearing 长衫/直裰 with beizi. 

Woman could wear them like this today too.

I re-read the question again and realized you said cross-collar ru. Technically speaking when ru was popular beizi hadn’t appear yet. The followings are example of cross-collar ru worn parallelly. 

There also is the possibility of Weijin-feng style plus a parallel-collar jacket, which was fashionable back in 2017/2018, but the jacket would most likely be a 大袖衫/Dàxiùshān. simply due to the sleeve size.

Some of my older post regarding the difference between daxiushan and beizi (x); between daxiushan and pifeng (x); and between daxiushan, beizi, and dachang (x).

I hope this answer your questions. I hope my answers is satisfactory. Do tell me if I make mistakes in the answer.

tl;dr: 

Pibo usually don’t go with beizi, but you can wear one if you like. 

Beizi could refers to many things due to its long historical used. In the beginning it refers to top that have short-sleeves or no sleeves, then it refers to long shan with decorative collar and cuffs.