If you read beyond the first paragraph, you'd learn what the author means by those terms.
The article starts with an example, and then goes on to explain the difference between immediate mode GUI and retained mode GUI is. It is well written and easy to understand article.
What you are asking for is a TLDR at the top of the article. Sure, that would be nice, but on the other hand I don't see anything wrong with writing a blog post that requires reading more than 50 words to fully understand the topic.
> If you read beyond the first paragraph, you'd learn what the author means by those terms.
Ha, you got me there! (I know the HN guidelines recommend to not suggest that someone hasn't read the article, but in this case I'm fair game.)
When I first skimmed the article, I only had a few minutes between tasks at home, so I didn't catch all the details. But since my initial comment stirred up some controversy, I figured I'd better take a closer read. (Well, still kind of halfway skimming since it is getting rather late here.)
In the next to the last paragraph was the clue that made it connect for me: "The OnGUI of Unity Engine actually uses IMGUI mode."
Aha! So this "immediate mode GUI" business is like OnGUI? Where you draw everything from scratch on every frame, instead of the engine remembering stuff for you?
That's when it all made sense, since I had done a bunch of Unity work 4-5 years ago and some of it involved OnGUI().
60654's comment led me to the current OnGUI documentation [1], where they even call it "Immediate Mode GUI (IMGUI)".
I'm pretty sure they didn't use the IMGUI terminology when I was working in Unity, it was just OnGui() with no other special name. Otherwise I would have remembered "immediate mode".
But it's possible that my memory is not as good as I hope it is!
The article starts with an example, and then goes on to explain the difference between immediate mode GUI and retained mode GUI is. It is well written and easy to understand article.
What you are asking for is a TLDR at the top of the article. Sure, that would be nice, but on the other hand I don't see anything wrong with writing a blog post that requires reading more than 50 words to fully understand the topic.