It is common knowledge that Luigi is just a palette-swapped Mario, and that the characters facing left are the same characters as those facing right, only rendered mirrored.

This interesting 9-minute video from Core-A Gaming explains how this can be kind of tricky for fighting games in particular:

Suddenly, a character with a claw on one hand, or a patch on one eye, becomes a more complex situation – without redrawing, the claw or the patch move from one side of the body to another. Then there’s the issue of open stance toward the player, turning left-handed characters into right-handed ones just when they switch to the other side.

3D fighting games can, in theory, fix all of this with more ease, as instead of redrawing hundreds of sprites they can just introduce one change to a model… but they often choose not to. Enter the issues of 2.5D fighters vs. 3D fighters, 2D characters in 3D spaces, and lateralized control schemes.

It’s a small thing that quickly becomes a huge thing.

Here’s an object in Figma with one rounded corner. Notice how the UI always tries to match the rounded corner value based on where it is physically on the screen…

…which makes for a fun demo and feels smart, but: why don’t width and height do the same?

Turns (heh) out that this is a similar set of considerations as those in fighting games: both thinking deep about what is an intrinsic vs. derived property of an object, and what is the least confounding thing to present to the user. Since objects usually have noticeable orientation – text inside, or another visual property – width still feels like width and height like height even if they’re rotated. The same, however, isn’t necessarily true for four rounded corners. Or, perhaps, the remapping of four “physical” corners to four “logical” corners can be more error-prone.

Then, of course, there’s a question of what to do when the object doesn’t have a noticeable orientation. Like with many of the things on this blog, there are no “correct” answers. This too is a small thing that quickly becomes a huge thing.