Those photos show what's called the Mura effect, or just mura. Usually that is a display failure, but you are potentially in luck. Take the laptop to an AASP or Apple store, and tell them to run the nVidia graphics chip test on it. Tell them to look up KB article TS2377 if they aren't familiar with it. You can look that up yourself, and see the basic info about the program. Service providers will see additional info about how to test and process things if your system indeed fails the test.
If it does fail, this is a special recall program so do not let them charge you for it. Apple will pay labor to the ASP so they aren't allowed to charge you anything unless you want to pay for an expedited repair. It will involve having your laptop's logic board replaced, because yours was made during the time when nVidia was trying to cover up the fact that it was producing a lot of defective graphics chips, in particular the infamous 8800GT which is most likely in your system.
You can give that a shot, and with luck it will fix the problem. If not, then it would be that your display is starting to fail. Assuming your laptop is out of any kind of warranty coverage, if there's no obvious accidental/abuse damage beyond normal wear, the system may qualify for Apple's flat rate repair service which is about $310 to fix anything and everything that's wrong. If there's any kind of accidental/abuse damage, particularly to the display assembly, then you may as well buy a new computer. The display panel would kick it to the highest repair tier which would be about $1300 or more. For a laptop going on 4 years old, the flat rate would be borderline whether or not it's worth it, the $1300 would definitely not be worth it.
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