Why not just use an IDE if you want IDE features?

After I posted about my Sublime Text 2 git plugin I got one response which I thought was worth responding to.

That looks helpful, but I often wonder why not just use an IDE if you want IDE features.

Obviously I have a bias here, but I’ll try to be fair to IDEs…

An IDE is an editor that does a lot of things, many of them well. If there’s something you want to do it’ll almost certainly let you do it, but if you’re not happy with some basic element of how it works then you’re stuck having to find a new IDE. (Yes, I know, many IDEs have plugins available, but I’ve never had that much luck with them.)

IDEs also tend to be built with a workflow in mind. If you conform to that workflow then they’ll be good to you, but you want to deviate from it you may have to fight with your tools.

A lightweight-but-extensible editor (e.g. Sublime, TextMate, vi, and so on) tends to focus on having a really good editing experience. So you start with good editing, and then you pick and choose the “IDE features” that you want to mix in. If part of the editor doesn’t work how you want you might have to find a new plugin for it, but since it’s not a massive and complicated system it’s likely to be easier to find that plugin.

Neither is necessarily better, but they do tend to appeal to different types of developer. Web developers, needing to work with a number of different file types, and not generally having complicated build system requirements, gravitate towards the lightweight editors.

UPDATE: To be clear, I’m not saying either is better. It’s a matter of personal choice and situation. As someone who mostly does web development in dynamic languages, I like using a fairly lightweight editing environment. If I wrote in Java I’m sure I’d be singing the praises of IntelliJ/Eclipse/whatever, because I understand that Java is almost impossible to write well without an IDE.

Sublime Text 2 git plugin

I wrote a git plugin for Sublime Text 2.

I’d decided to try Sublime out for work to see how it compared to TextMate… and thus some degree of git integration was required. Given that it’s been out since January, I was surprised that there wasn’t already a solid git plugin.

I did find this one, admittedly, but I decided that I didn’t like how it fit in with Sublime. It’s built around menus and keybinds, whereas I felt that setting everything up as commands in the palette and hooking as much stuff as I could into the fuzzy search was the way to go.

Working on the plugin was a good exercise in getting me used to Sublime. I’m fairly sold on it as a result. It’s philosophically somewhat similar to TextMate, but with some of TextMate’s rough edges smoothed out.

(Short rant: if the recently announced TextMate2 alpha doesn’t get rid of the single-character undo buffer… I don’t know what I’ll do. It’s certainly the biggest single complaint I have about TextMate nowadays.)

A shadow is upon us

Other people contributing to my projects is often the cause of my improving them. This is because people tend to contribute something that works for the case they care about, without necessarily testing how it combines with the rest of the product. There’s nothing wrong with this. They did some work and wanted to give it back; that’s how open source should work.

A case in point here is how shadows just got added to maphilight. A pull request was submitted for a commit that added shadow support for rectangles in canvas only. I accepted the request because, hey, that’s a nice improvement, and it seemed to work. But I wasn’t really happy with rectangles-only.

So, I started fiddling with it. I had, for whatever reason, never touched shadows in canvas before. In fact, it’s been quite a while since I did the research into canvas that was involved in writing maphilight in the first place.

Looking at the commit I see that the shadows have been implemented with a combination of clipping regions and redrawing the shape with some shadow options on the path.

Now, I’m confused by the clipping being done, since I’ve never seen it work quite like that before. It’s drawing a rectangle around the whole canvas, then another around the rectangle we’re shadowing, and telling it to clip. So I do a bit of testing, and I find that this isn’t doing what I think the submitter meant it to.

I think they wanted it to set up a clip region only outside the shape, so that the shadows they drew wouldn’t appear inside it. However, in practice it seems that it’s just adding the two rectangles together and leaving us with a clip region the size of the whole canvas. It’s possible that this did work in another browser, but not in Chrome where I was testing…

Since subtractive clipping obviously wasn’t the answer, I looked into globalCompositeOperation to clean up after the fill. It turned out that destination-out was the operation I needed to empty my shape. Also, because the shadow-drawing had been added after the regular shape, I had to move it to be before that, otherwise the shadow was being drawn on top of the stroke and cleaning it up would wipe out the fill.

Okay! Now we have outline shadows.

But, another issue with this method: it’d fill and stroke on the shape, regardless of the settings you were using. If you had no fill / stroke it’d use the default (flat black) settings, which are ugly. Also, it harmed your opacity settings — the stroke and fill were being done twice. So when I added a shadow to a strokeless mostly-transparent rectangle I noticed that it gained a thin black outline, and was darker than it should have been.

I messed around a little bit with trying to erase the fill or stroke, but eventually decided that this was more hassle than it was worth. What wound up being the simplest option was drawing the shape massively off the edge of the canvas, and using shadow offsets to cast the shadow into the right spot.

Now we had a shadow that didn’t involve drawing anything stroking or filling onto the canvas near our existing shape. At this point I had completely rewritten the code I’d merged in. About the only thing remaining was the option names Raven24 had chosen.

I went ahead and added some options for whether the shadow was cast inside or outside the shape, since I could see reasons for both, and added some overrides for whether it’d be casting from the fill or the stroke, since the varying possible configurations made it difficult to reliably guess which would look better.

I still didn’t add it to non-canvas. Largely because now that IE has finally given in and implemented canvas I view that as being a dead branch. Needs to keep working, and any major changes have to be ported over… but minor display differences are somewhat acceptable. Also, I don’t have access to IE right now, since I’m away from home. If I ever have reason to look into shadows in VML I’m sure I’ll add it in then, for the heck of it.

You can see all this in action on the demo page if you’re interested.

And that’s how community involvement improves things. 😀