Ipad screen orientation

How does the ipad know if it should pick landscape or portrait orientation. How does it know where I am sitting?

It doesn’t know where you’re sitting but it knows which end of it is higher than the other end.

Not only does it know what orientation the screen is in, it also knows the angle in three dimensions.

Actually, it always seems to pick the correct orientation even if it is flat on the table.

Because you set it down correctly. If you set it down in the wrong orientation, it won’t correct itself.

the iPad has an accelerometer which can sense which side is “down,” thus rotating the screen so it’s right-side-up by your perspective.

I just want to be sure I understand the terms. The ipad is laying flat on the table. Toward the sky is up, toward the floor is down. We’ll call the top of the ipad north and the bottom of the ipad south. Does the acelerometer know down or south?

Beowulff, you are right. When it awakens from sleep it orients the same as when it went to sleep. I was always in the right spot, and I didn’t realize I was interpreting this as the machine knowing where I am.

I assume that if it was an iphone Siri would have known where I was.

The iPad knows it’s orientation in space in 3 dimensions. What it does not know is where you are located in respect to it - if you set it down perfectly flat, and walk around to the other side, it won’t rotate the screen. The reason it picks the correct screen orientation (usually) when you set it down flat is you set it down in the correct orientation to begin with.

ETA: I see you’ve understood what I was saying.

BTW, there are some neat games that use the accelerometer - try the “Labyrinth” game - I think it’s still free.