Welcome Aurel. I think you're going to really like Construct 2. It's incredibly powerful and usable program.
That said, so is Game Maker Studio. I've used both kits now for some time and like most software each has it's plus and minuses. My perspective is from the Arts background similar to yours, so it's possible some of my opinion may overlap with what you experience.
"this is from my experience so others my disagree"
Both C2 and GMS are capable of making games with the level of detail you mention, for the desktop.
Both can export desktop apps for Win and Mac and Linux with the same high level of detail. C2 does these 3 platforms using node-webkit. And it works great. GMS can do Win and MAC in "standard" version at a lower price point then C2, But if you want Linux that's and additional $99 making it the more costly option.
GMS wins in the Mobile department on all fronts compared to C2, but you pay a lot more for the privilege. I don't doubt that at some point the 3rd parties that C2 use or will switch to in the future will match this. But at present they don't. And frankly as an artist I'd rather spend my time making my project better instead of dealing with limited features and workarounds. I'm not saying C2 can't do mobile, it can and does, I have a few good ones on my phone right now. alongside some GMS games, Both work well. But it takes more dedication to pull it off as a C2 dev then a GMS dev .
The single best thing I can think of if you really want to get the differences between C2 and GMS is to try and make the same small prototype game in each software. That will tell you all you need to know about both. having done this it becomes very clear which tool is right for which projects.
Some other possible helpful things you may notice coming from GMS.
1. Ironically given Game makers history as a learning tool. Construct 2 is easier to learn , has better tutorials/examples. And the usability of it's IDE is light years ahead of GMS.
2. GM community and C2 community are great and filled with helpful people. But if you can't have a tie C2 wins.
3. Ashley and Tom are more involved with their users and community than any other company that I have ever bought software from.
4. you will be blow away by the speed of the release cycle. if you're used to Yoyogames.
5. as you have noticed the behaviors and plugins "1st and 3rd party" and incredible from a GMS point of view. learn them and love them. but realize you just won't have the fine grain control you are used to with GML in all cases.
6. prototyping is faster with C2 in most cases if your are using the built in behaviors. But complex scripting/eventing is going to be much more long winded in C2 then GMS. Due to it's nature C2 just does not allow you to do some of the tricks GML can.
7. "picking" is very different in C2 then GMS, it will take a bit to get used to. it's not worse or better just different. but my lead to said long winded events.
8. You will need to make sure each object exists on some layout "room". before you can use it, or you will get errors. This is different then GMS
9. C2 will not let you create events that won't function. As it won't let you pick objects that won't work, or close a window if an expression is malformed. GML will let you make all the errors you want but will give you helpful hints or error messages so you can fix them. Both ways work, both ways can get frustrating.
10. C2 has the better debugger. This is a recent victory for C2.
11. Community plugins are really active for C2 and many great ones exist. Community shader activity for GMS is almost as robust. Given how new it is that's says something for GMS. C2's Built in shaders are more powerful presently.
13. your "control objects" are now just another event sheet that you include into your first event sheet. you can now think of them the same way as GMS
14. check out image points. and be boggled as to why GMS never bothered to have something this simple and useful.
15. C2 does not have anything built in like tiles, it's not missed much once you get used to they way c2 works.
16. GMS "scripts" are best done using the Function object , they work pretty much the same.
17. You do not have any control over the "draw event" nothing equal to that exists for C2.
18 C2 has one "view in room" and no "port on screen" beyond changing how the view scales in the browser. C2's view_xview and view_yview, are scrollx and scrolly and return the center of the view not the upper left edge.
19. C2 IDE is less stable then GMS IDE. If C2 refuses to close after using it a while don't worry that's just the way C2 is for a lot of people. I'd also suggest saving your projects as projects and not as a single file.
Well that turned into a wall of Text sorry about that.
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