Today I implemented tile walkability and looping sprite animations. Note that the guy can go places the car can’t.

It is spooky to me how quickly this has started coming together after two months of tech fiddling. It... paid off? I’m not used to this.

Project has suddenly started immediately terminating on startup, like, before my code even runs??

It looks like maybe the 512-byte cache I just added somehow exceeded my 64kb RAM budget and Turbo C++ just doesn't tell you when you're over??

so remember when I was like “oh the source of all my startup performance problems is definitely byte-at-a-time unbuffered file reads”? https://mastodon.social/@SpindleyQ/101648207901180365

So I implemented a file cache and startup speed stayed pretty much the same. Turns out the problem is actually that tight Jorth loops over thousands of items are Not Fast :/

Hmm, interestingly the interpreter I defined in C is no faster at compiling all my Jorth code than my bootstrapped interpreter written in Jorth, which I guess makes sense given how little code it is

So it’s really the general VM overhead that’s killing me, and to solve that I’ve really only got two options:
* start rewriting the VM in assembly
* precompile code into an image that can be directly loaded into memory

Implemented traveling between areas! Each area unloads its code before loading the next, which should allow me to ensure that I don't run out of RAM to hold text. (I think I've got about 6kb left which _should_ be plenty, I hope...)

Definitely need to design a little helper DSL for defining reactions to the player bumping into areas without sprites, that code is already getting ugly...

Built my DSL - all my player collision code is much cleaner now.

Basically I have N things I need to check before I move the player - is it bumping into an object? Is the terrain walkable? Am I leaving the bounds of the map? - and if one of those questions is true, it needs to optionally perform an action and bail early on the rest. "else if" is not really a workable concept in Forth, so I needed to find another way to simplify this.

Oh no I have completely run out of fun tech to build and now I have to make maps and write and draw stuff. Haaaaaaalp

I’ve made some progress with this but I don’t wanna post a constant stream of screenshots of everything I map out because then y’all won’t have any surprises when you eventually play the game.

Slowly realized that the speed of Jorth’s interpreter is likely bottlenecked by symbol lookup. Implemented an easy standard optimization I hadn’t bothered with (don’t do a string comparison if the lengths don’t match!) and suddenly cold startup goes from almost 30 seconds to 20 seconds.

Still glad I built precompiled image support but that’s a significant win

So my game loop was calling "tick" and "draw" by looking up the words in the dictionary every frame. Decided to cache the lookup; not as a serious optimization, just as a little cleanup.

Did I mention symbol lookup is by far the slowest thing in my Jorth interpreter? HOLY SHIT the game runs SO much smoother now. I couldn't believe it, I just started wandering around in-game, marvelling at how the animation wasn't stuttering, with a huge grin on my face.

aaah I came up with a cool idea that fixes a bunch of story problems I was having. I wrote a _bunch_ of new stuff for the game today (in comparison to... literally any other time I've worked on the story)

might actually finish this thing someday after all

Remember when I started this project in December? Today is when I finally have access to a working serial mouse.

Out of all the retro hardware I have had to scavenge I did NOT expect a serial mouse to be this much work!

"Hey Jeremy why are you writing your own sprite editor" I mean, besides the obvious "building everything myself the hard way" reason, see this toot from February? https://mastodon.social/@SpindleyQ/101661425411468111

I realized that I was trying fruitlessly to design the finished game without drawing any more tiles or sprites because my NeoPaint workflow was so miserable. And that's ridiculous because I enjoy drawing _way_ more than writing and there were a bunch of elements I wanted to put in that I haven't drawn yet!

Saving and loading wooooorks

My sprites are now stored only in my custom format (which is just a straight memory dump) instead of TIF, and I don't have any code to SAVE TIF files, so, goodbye forever NeoPaint I guess, I hope I don't need flood fill and that I never irreversibly corrupt my sprite file

Adding background tile editing to my in-game sprite editor and man EGA graphics engine glitches are FUN

(Video: a mouse cursor acts as a flashlight illuminating a square of correctly rendered tiles while most of the rest of the screen is either black or random tiled garbage, in the vague shape of the starting map)

I made a boat

It’s a good boat

I also added a bunch of features to my in-game sprite editor to make making the boat go more smoothly

Like, copy/paste of tiles & sprites, horizontal flip, nudge up/down

It’s SO much nicer than NeoPaint now