I think outside views in quality 3 and 4 depends on the sky texture. Maybe the images I provided are too blue.
I'm curious too see how horizontal maps provided at http://blender-archi.tuxfamily.org/Textures#Horizontal_maps would render.
By the way, I released version 2.3 Beta 10 that improves walls in the 3D view:
Hans, it should fix the strange behaviour you noticed, and Richard, it doesn't break up the texture applied on a wall with openings anymore.
One last thing, nobody ever complained about the color used to draw the top of walls in the 3D view. I'm opened to change it if you give me good ideas.
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Emmanuel Puybaret, Sweet Home 3D creator
