Image Size Trade-Off?

Why are most professional game images square and in dimensions of 2^x? If I have an image of 3000 x 1500, would it be better to take more memory and make it square to 3000 x 3000, or even go all the way to 4096 x 4096?

because they map to graphics card memory better that way… you should also make them multiples of 2:

32, 64, 128, 256, 512, 1024, 2048, 4096…

so in your case 2048 * 1024 would be the closest fit…

if it’s for a modern games console it’d be rare to be larger than ~ 1024 as a maximum dimension though… and most textures would be smaller than this, working in sets to tile…

oh and video games use formats like dds for final output as they give good compression ratios and map to graphics memory better … don’t EVER make your source dds though… it’s lossy and degrades horribly if you edit it!

I’m only using such a large image because I have an entire deck of cards mapped to one image (It makes it simpler if I edit the image).

Why not save final images to dds for game compression, but keep another tga or png file for editing if needed?