I've started using maps straight from AP's or Modules and noticed that a lot of the objects (tables, chairs, whatever) often are drawn into 2 or more squares. If one of my PC's ends his turn next to a table that is between 1/4 to 1/2 of the square is he considered squeezing as the square isn't a full 5'?
If you are sitting in a chair and stand up, meaning you are still in the square with a chair that covers over 50% of the square, as drawn, are you in an illegal space? Squeezing? or is it as simple as being in an object square costing double movement?
I'm looking for what the penalties would be for said squares on both a movement cost, AC cost and Attack penalties.
There are two ways to handle objects like those that are drawn in artistic renderings of maps if the object is not necessarily immobile like a wall, pillar, or door, i.e. For tables and chairs, etc.
#1 You can just ignore them as there are really no set rules for things like that.
#2 You can count them as objects and as listed under the combat section of th CRB they are can hamper movement like difficult terrain or they can block movement entirely.
I would call out objects to the players at the beginning of an encounter especially if they are on the map and cross over a square or the edges. I would not usually count them as squeezing.
If you want to get complicated, you could use the squeezing rules and have smaller creatures be able to run under tables and such, but I do not think the rules will cover each nuance created by an artistic map with furniture and such on it.
That's a good question, and I also don't think there are rules for it. I tend to handle obstacles that don't completely block a square's movement (like a chair or a table that's partially in a square) as difficult terrain. I would only apply the squeezing rule if I'd literally imagine the character not being able to freely swing their arms or stand up straight because of an obstruction.