Cat needy to aggressive

I recently moved in with my girlfriends family who have a 7 year old cat. This cat was severely neglected for as long as he's been with this family. Around other people he is very shy and gets scared very easily. The family also has 2 dogs and one of them chases the cat all the time and scares him even more. The cat also tries to attack the other dog, who is blind and weak and can't see him coming. After I moved in I noticed how little attention the cat gets compared to the dogs so I started spending all my time with him. After a while he has gotten very attached with me and he is almost never afraid of me. He has never asked anyone for anything through meows but he definitely meows at me until I give him what he wants ( food or cuddles). A few weeks ago he started acting strange. He has always loved to cuddle with me and he enjoys when I pet him while he falls asleep on my lap. He is very needy for love and he loves to sleep on my lap. Recently he's started acting aggressive once he wakes up from this nap. He'll be sleeping and then suddenly wake up, intensely stare at me, and then meows aggressively. His meows only get louder and he starts getting closer to me to attack until I freak out and make him get off me. I've tried slow blinking, I've tried giving him treats, and I've tried avoiding eye contact but none of these have worked when he's like this. I just want to know what I'm doing wrong and how I can make him not so angry with me. He doesn't behave like this around anyone else in the house but he also doesn't like to sleep in anyone else's lap. Please any advice from anyone else who's dealt with this would be amazing. Thank you.

Have you tried playing with him? 

It sounds like he has been in a situation where his only play buddy is the dog he chases. Now he has found a human who wants to spend time with him and as he has gotten comfortable he is trying to initiate play. If he hasn't had a lot of experience with play it may come across as more aggressive because he doesn't know better. You don't want to engage in play with your bare hand because he may hurt you on accident by not knowing how to play with humans. A wand toy is good for those cats who don't know play rules because it keeps your hands safe and gets them moving. You can get small mice and ball toys to toss around at most pet stores for under a dollar each (or just crumple up some paper into a ball). Unlike dogs, he likely won't bring them back, but if you get a few and throw them he should run after and bat them around some. Depending on him he may be content with just batting one around or you may need to pick them up when you run out to throw again. 

I haven't tried playing with him but I'll definitely try it if he does get that way again. I remember before he started acting this way I used to put my hand under the blanket and move it around and he would try to chase that. I already have a wand toy for him so I'm gonna see if he tries playing with it. He's not the most playful cat usually but I'm not sure if that's just because no one ever really tried to play with him or that he just doesn't want to play. Thank you so much for the advice!!