Perspective allowed for much more life-like paintings and allowed for a three dimensional look.
Answer:
It can be anytime
Explanation:
It's a mix of many factors, for example, you should feel like it's ready but your audience should be interested in it too!
Art is just like any other primary source as it shows what happened in that time era, what everything looked like, how people dressed and so on
Juan gris’s art is about something you have to figure out, whereas Picasso’s is about people’s life, music and joy. Hope this helps