A while back I tried to paint an interior with lots of tile work on the ground and on the walls. It all looked so easy, but I run into all sorts of perspective problems and wished I had seen this little trick, before I ever started. My painting is unfinsihed and sits in a corner now, but maybe someone can benefit from this cool idea...
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The video provides clues on how Vermeer painted his room interiors, such as in this painting by Vermeer called "The Lesson"