Chat about the original Pixelmator.
Hey! Pixelmator Pro doesn't work with vector PDFs and opens them as regular images so it has the rasterization covered right off the bat. Resolution changes can be done in the Image Size options that you can access from the Image menu. The only thing that might be tricky is the antialiasing part. There isn't really an option to turn it on or off. But there's a Threshold effect that can come in handy in some scenarios where a black & white, antialized image needs to be created. All these functionalities are there in Pixelmator Classic too by the way, only in Pro, they might work just a tad bit smoother. There's a free Pixelmator Pro trial you can download right here if you're like to test them out.