Complex sentence: These two great artists influenced Renoir's entire way of painting and drawing: he began to paint in a more disciplined and more conventional manner, gave up painting outdoors, and made the female nude--previously absent from his paintings--his main subject.
Split into simpler sentences: These two great artists will now influence Renoir's ay of painting and drawing, who will now paint a more disciplined and more conventional manner. He gave up paint outdoors and made the female nude-which was previously missing from his paintings-his main subject.