Saturday, November 19, 2011
In Profundis Progress: Tools, Inventory and personal coding deficiencies
This is about the place where my general lack of experience with modern (that is, post Commodore) development is biting me hard. Something I've been worried about is the representations of user-placed items in the world. There are three general possibilities here, and I've messed around with each one to some degree. Possibility one is to implement them as sprites, that is, as moveable objects that can move independently of the cellular grid, like the player can. This is what I tried first, but after a bit of that I realized that it really wasn't a good solution. Part of what makes tools interesting is how they can interact with the game world, and every object that isn't part of the basic world model, even if it's grid-aligned, complicates the code. However, it gives rise to the problem with possibility two, which is, define special tiles for in-world tool objects. It looks weird when water flows around a piton as if it was a full-block object. And a lot of tools are like this. It's the existence of liquids and gases, which are just cheat analogues for sub-grid-level phenomena, that makes this an issue. The nature of the game is such that, if push came to shove, I could probably get away with doing it that way anyway, but instead I'm opting for possibility three, which is to give each cell a tool field that can contain its own object. This way liquid can flow past a piton without overwriting it or flowing around it, and objects in lakes can rest there without making an air bubble around them. Now the better programmers out there are probably wondering why I'm spilling words on such a decision. It's because, really, this is the most complicated project I've ever worked on. Mayflight's world builder was more complex, but its world simulation was just a platforming engine. I'm somewhat out of my depth here. At least writing this in Python means I don't have to muck around with (overt) pointers and worry about the myriad bugs those can introduce. I visit anna anthropy's blog pretty frequently, and I've been known to chuckle to myself when I read about her aversion to coding. I really can't imagine doing a whole game using, say, Game Maker's abhorrent drag-and-drop scripting functionality -- I always tie each event to a text script. But really, I'm just one step further along the path than she is, and there's a dozen ahead of me. What is funny is that I was a quick study back in programming classes, but there's something about pointers that screws me over. It's not that I don't understand them -- far from it, I have a strong processor-level understanding of the things. I did a fair bit of assembly programming back on the C64. But something about the way C-style languages approach them trips me up hard. I'm constantly confusing where I need to use * and where I need to use &. I know that * is a pointer to some value, and & is the value that a pointer points to, but I don't seem to have it internalized to the point where I can write code with those symbols confidently. I wouldn't be surprised if I had some form of dyslexia tripping me up there. The language is such that you must know what is a value and what is a pointer to a value, but I nearly always get them mixed up. This, coupled with the fact that I was continually stymied by import errors, was probably what sabotaged my attempts at restarting In Profundis in C++. Game Maker is really not that different from C in syntax, but its garbage-collected, reference-counted scripting was the breakthrough feature that got me productive with it. I'm just blabbing here really; I felt guilty that it had been a little while since I made a post here. Anyway, working in inventory and tool simulation now. I hope to start putting in the backer treasure data before long, so that'll be fun at least.