I am afraid for some people such a sticker might be encouraging rather than deterring...

That's kinda where I am at now - I used to have hardcoded values for everything, but now I moved onto data files (used to have my own binary format but moved to JSON). Abilities, for example, work more or less as OP described - they include a list of things that happen, and the actual code defines each of those things (such as "deal magic damage based on weapon/magic stat/constant" or "revocer X HP over X seconds"). That includes even the visual/sound effects like "throw a fireball particle towards target". To tweak a specific ability all I need is to tweak the data. To add new effects - code.

At least one MMORPG I have played calls this "reawakening", but I think "rebirth" is also thrown in some of the texts, not sure though.

I halfway remember a method that involves drawing the same texture, but enlarged, as a kind of an overlay, preferably a couple of this at different frequencies, but I cannot for the life of me remember what it was called

@Kevin the user experience, mostly, even with all kinds of ad blocking enabled.

@Kevin here's a link to a non-Wikia mirror: zeldawiki.wiki/wiki/Three_Heart_Challenge

this looks like a general programming question rather than specifically a game development one

@DMGregory good point, it does look like too much of a jump to be that, and it seems to be very consistently 0.075 every time +/- what is probably the actual round error (or a small range within which it is nice and continuous?) so the question is where this specific value emerges from

@BlueRaja-DannyPflughoeft funnily enough the comments on that one say the opposite of the consensus here - design stats first and then work the math to make them work

What is the overload you have used that did work, without the horisontal flipping?

I believe the old Harry Potter PC games used some kind of a mask and then checked coverage.

Can you please provide the exact output of debug,log for source slices and maybe also destination slices? Maybe add a breakpoint right after the log statement so the program pauses instead of spamming the log 60 times per second or whatever the framerate is. I strongly suspect that the code you provided wants the bottom/right paddings as relative and not absolute values - I tried to "run" the function in my head with your suggested input and it did give the garbage values. As an example, you might want to have left/right as 32 and top/bottom as 16 in your source slices.

Not an answer (I cannot make the time right now!), but I solve a similar problem with a dedicated struct for a 9slice. It takes outer dimensions and margins and turns them into 16 points, which are then used by the renderer to create the 9 quads (rects in your case) to actually draw. github.com/htmlcoderexe/3DGame/blob/… The code that uses this data structure is in RenderFrame inside GFXUtility in the same folder, you can follow it from there.

If you disable the code that moves the rectangle after collision - do the debug lines show correct sides?

Huh, another great reason to keep chunk sizes at power of two sizes...