Relative texture sizes, platform specific max sizes, and sprite atlases


I am trying to figure out how these parts all work together. Let’s consider the following example:

2 files on disk:
ImageA is 500x500 (250k texels)
ImageB is 100x100 (10k texels)
This means ImageA uses 25x as much texel space as ImageB

The 2 sprites imported into Unity:
ImageA has had it’s Max Size reduce to 128x128 (16,384 texels).
ImageB was not changed from the default value of 2048x2048, meaning it keeps it’s disk size of 100x100 (10k texels)
This means ImageA now only uses 1.6x as much texel space as ImageB

Both of these 2 sprites are added into a Sprite Atlas. There are many other sprites already in the Sprite Atlas. The Sprite Altas’ Max Texture Size is set to a value large enough to fully contain all sprites at their Max Size setting.

My question is about how much relative space ImageA and ImageB take up within the Sprite Atlas.

Will the used space of ImageA within the Sprite Atlas be 1.6x as much as ImageB? Or will it be 25x as much?

Thank you

All of this is completely dependent on your import settings, including compression, cropping, max-sizing, etc.

Just go construct a test and look at the build report to see sizes in build.

Then attach the profiler and see how much memory each one takes.

For all performance and optimization issues, ALWAYS start by using the Profiler window:

Window → Analysis → Profiler

Thank you for the response, but I don’t see how any of those things are related to my question.

Maybe I should try to reword things.

I am asking about which set of file sizes the Sprite Atlas uses when placing the sprite into its atlas texture.