Hey!
So, I was banging my head for a very long time to find out the solution for the below-
Problem- I imported a 6200x1080 AI vector file in After Effects, which was a cityscape view. As suggested in all forums, I turned on the Continuously Rasterize option (small sun icon near the shy button). This removed pixelation if I scaled my vector, to any infinite value. But, the problem still remained with composition camera zoom, which is where the artwork still got pixelated if I zoomed in my default camera.
After Effects will pixelate any vector if you zoom beyond 100% in preview. So, I tried adding a camera with 200mm focal length. I did not want to animate the scale of my artwork, but rather wanted to work with my camera. The next problem was, when my Illustrator precomp was turned 3D, the camera I created does not really work whether I zoom or pan (this happens when continuously rasterize option is turned on for the precomp). When I turn off the rasterize option, the camera settings work again.
So, I needed a way where I could use my camera zoom and pan settings along with full quality vector even when zoomed in to 1000%.
Solution- This is what worked for me. I imported my AI file (as composition retaining layers) and opened the comp. I turned on the option of continuously rasterize for each Illustrator layer and also turned all of these AI layers into 3D. Next, I imported this comp into a new comp and made the precomp layer 3D. I added a 200mm camera. When I zoomed in with camera tool, it zoomed in but still there was quality loss. Now I turned on the continuouslyrasterize option for this precomp layer as well (which I had made 3D) and voila!!
Now, I don't have to scale my vector art, I can zoom in as much as required with my camera tool with full vector quality and animate my camera settings as well!!
I hope this turns out helpful to some people. I started writing this forum as a problem but trying to explore in the meantime, broke through the solution, so included the same here as well.