Hi There,
I’m new to Ambient Occlusion. I’m trying to use it as a simple means to render my SketchUp drawings which are interior spaces. I have a piece of furniture in one of my drawings. It’s a living room with 2 matching armchairs side by side. It’s supposed to have black stained wood arms but one of the chair’s wood arms is showing up as a purple textured fabric. I deleted the chair and just made a copy of the one chair with the right wood material fill. Still showed with fabric for arms. Then I changed the color to solid black arms. Then when I rendered the image again the arm on the one chairs shows as marble (like the fireplace). What is going on?
I tried floating the chairs in the air and the arms show as black when rendered. But I can’t have them floating in the air!
An explanation would be greatly appreciated.
~m
Hi 
A common mix up with materials is that AmbientOcclusion uses the material of outside face while rendering; despite which side is actually seen out. You can check which face is inside in and which outside when you set the view to monochrome (View->Face Style->Monochrome). Then you see all the faces only as white and grey. The white face are the outsides and their material is used in rendering.
If there are seen grey faces, you should select them, right click, and select “Reverse Faces”. In the same right click menu, there is also command “Orient Faces”, which turns all the connected faces to same orientation as the one you selected.
When all the faces are oriented correctly outside; then check their materials and let the AO render again.
Verify your objects that it doesn´t be a component, or have more than one grouping level
