Toward a 2D Game Engine: Reflections

Two things that have become really obvious through this process are that a) my C++ skills are really rusty, and b) my expectations are grossly unrealistic. The idea of how long something should take should be calculated only by my present abilities, not by ideal circumstances if only I were in possession of all the relevant knowledge and an industrious disposition.

This is not the first time I've tried doing this, and even back as far as university I tried and failed to do similar. I've read a lot of books and articles trying to find the right answers (or meta-answers) to the questions I've had, but I've failed to be satisfied by what is written. Though well-meaning, the tutorials are especially bad precisely because they break basic design principles for the sake of illustrating a point. The closest to what I wanted was the book Game Architecture and Design (Dave Morris and Andrew Rollings), which had a chapter on engine design. But, again, it’s a sketch of the problem – a 9000ft overview that has to somehow be distilled into discrete complementary units.

That, to me, is where the difficulty lies. It presses the question of why I should bother to begin with. After all, there are plenty of other people much smarter and more educated than I who have put the tools out there to take care of it all for me. To name two examples, there’s RPG Maker, as well as GameMaker Studio, which have a track record. But the trade-off is whether to spend the time learning how to use those tools over designing a system I know how to use. If I were more creative, perhaps those options would be better. But since I'm not overflowing with game ideas (I have 2.5 ideas that could be prototyped at this stage), building the engine itself is what I would consider an endpoint.

What I will consider the end of phase 3 – and I'm hoping this phase will be a completion of code rather than a period of enthusiasm – will be to get a few more core engine features developed such as getting in-game text, the level/tile/camera system, and menus. This seems weeks away, where I understand weeks away in a more realistic rather than pessimistic outlook. Perhaps if I were more competent, I could say a matter of days. But it is a hobby, and a hobby has to work around the rest of life.

One concern, always, is the availability heuristic. That is memories of what I've done previously are going to be tainted by the most pressing issues that came to mind – which in my case is the failure to make headway. One hope in writing all this out is that next time I go through this; I have a record highlighting what I think worked and what didn't. Writing it out gives me a meta-plan for the future, with processes and structures of what I ought (and ought not) to do.

I think this time, though time will tell, I have reusable code. The extra time I spent trying to get the design right may have been a headache (and a significant de-motivator), but I haven’t taken the shortcuts that evidently and inevitably crept through my old code. There was nothing in the rendering class, for example, that was coupled to anything in Snake. Snake depended on the Engine objects, but the engine objects were not constrained that way. If nothing else, I can take that away as a victory of good design.

The graphics that were loaded came from an XML configuration, just as sound and music did. The Engine was flexible enough for the game objects to be used by ID, and that would apply just as well in Snake as in any other game. Even to make an animated food object in snake required little more than updating the PNG, the XML, and what type of object it was. The engine objects took care of the rest. And, at least by my reckoning, that’s the way it should be. To embellish or replace the graphics wouldn't even need a recompilation!

At the end of it all, I don’t know if I have better design principles than I did going in. I'm not even sure if what I did was right (though I'm very much of the opinion that what works is right), but from my perspective I don’t care. I'm not teaching anyone else. I'm not writing a textbook or a manual. This is to achieve what I set out to do, and I'm getting damn close to that goal!