Android: Optimize for high-dpi devices only but still support (small- and) medium-dpi screens

Question

I'm building a game with graphic assets in hdpi resolutions (hence I put the files in drawable-hdpi directory). I don't want to have a corresponding mdpi resolution of the images, and I will code everything in 240-dpi based pixel coordinates.

Is it possible to still allow mdpi and ldpi devices to run the app, by automatically scaling the graphics from the hdpi version?

Answer 1

If you put the graphic assets in drawable (with no qualifier) they will be used by all 1.6+ phones and scaled as appropriate for the screen resolution of the phone. You only need to use hdpi if you want to provide different assets for different screen densities.

Answer 2

You should put the assets in the drawable-hdpi/ directory. Phones will scale them down automatically with the following ratio:

3:4:6:8
l m h xh

So your hdpi assets would scaled 3:2 on a mdpi device. If you only put them in the drawable/ directory, the system uses mdpi as a baseline, and your assets will actually be scaled up on hdpi devices.

Note: If a density qualifier is not defined in a directory name, the system assumes that the resources in that directory are designed for the baseline medium density and will scale for other densities as appropriate.

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