How to create a smooth zoom for 2D games from scratch? (SFML)

YesBox · 2022-05-30T20:00:32

How would one go about creating a smooth 2D zoom from scratch? I'm using SFML/C++ for my game and the built in zoom feature is awful. Unless you're zooming in multiples of 2, the pixels will pop in and out of existence, or be different sizes, and when you move the “view” around, the pixels will flicker and pop in and out of existence some more. It's headache inducing. I cant stand it. SFML is otherwise perfect for my needs and I'll put in the work myself to work around this thorn. I know better zooms exist (though the different pixel sizes may be unavoidable, at least they wont disappear), so this is possible. The way I am working around this limitation right now is by having a tile atlas PNG for every zoom level (multiples of sqrt(2)). Obviously this is a lot more work for me, though I created a script to generate each sprite sheet to the appropriate size for each zoom level and adjust as needed. Any tips would be greatly appreciated.

Graphics and GPU Programming Programming 2D Graphics SFML

Started by YesBox May 05, 2022 01:01 AM

10 comments, last by YesBox 2 years, 3 months ago

YesBox

Author

May 30, 2022 08:00 PM

@undefined I appreciate the detailed response. Unfortunately there is no documentation or user examples I can find regarding using SFML's mipmaps. I tried generating a mipmap for each tile atlas texture, wondering if it would benefit the view.zoom() calls. But no, same issue as before. I'll just have to continue using a tile atlas for each zoom level I want in game.