"Painting a picture" is a common phrase used to describe someone trying to explain something obvious or clear, often to a person who seems to be oblivious to it. However, there are several synonyms or similar expressions that can be used to convey the same idea. "Do you need a demonstration?" or "Do I need to draw you a diagram?" can be used in place of "Do I need to paint you a picture?" These phrases represent the speaker's frustration with having to explain something obvious and the audience's inability to comprehend it without extra clarification.