NeoToxin development

Development source code released

2005-01-09T19:41:00.000-08:00

I've released the source code I've been working on the past month. It includes a small demo to illustrate some of the capabilities. The source code can be downloaded here. A precompiled ROM can be downloaded here. All that's needed now is great graphics, level design, enemies and quests, then Neotoxin is ready to hit the shelves!

Assembler mania

2005-01-08T22:35:00.000-08:00

I've written an assembler for my NES virtual machine. It's very crude (had to be since I can't afford to spend weeks on it), but it's sufficient for the time being. Ideally, I should write a compiler above it, but that's a bit of an undertaking, so it's not too high on the priority list right now. It's also a good exercise to code in assembler first so I can better see the requirements and implementation strategies of the compiler.

I've also released yet a new version of my assembler/linker suite. Bugs are still steadily trickling to the surface as I work on the Neotoxin code (it makes for good test input now -- 70 units, 11,000 lines of code), and every time I release a new version I swear "no more... there can't be any more now, can there?". THIS time, of course, it's true.

Next week I begin working on my master thesis, so NES development is likely to be somewhat subdued. Rest assured that Neotoxin will still be worked on steadily, though.

Wowser.

2005-01-07T11:39:00.000-08:00

During the last two days I've implemented dynamic memory management on the NES and built a virtual machine on top it. The virtual machine supports non-preemptive multithreading and is quite cool. The plan is to use it to implement scripting of game events (cutscenes and quest logic). I need to write a compiler for it though, since typing in the bytecodes by hand isn't very fun.

The 2D engine is pretty much finished now. It's all very tight; the entropy mentioned in an earlier post has been driven into the ground.

Status report this, status report that

2005-01-03T13:53:00.000-08:00

I've come up with new novel implementations of object-to-object collision detection and dynamic object loading/unloading. I've also released a new version of the assembler/linker, which adds support for anonymous unions.

Status report: The sequel

2005-01-01T18:12:00.000-08:00

Another year, another pathetic attempt at finishing Neotoxin.

For those who don't know, I'm rewriting and restructuring large parts of the code since the entropy of it all got out of hand, due to the combined effects of bad memory management, cheap hacks and long compilation times. The premise of this conversion is the advent of my amazing 6502 assembler/linker suite. Since the last report, I've made important progress:

- Animation engine completed
- Object physics engine, per-tile collision detection implemented

The focus now is on:

- Dynamic object loading/discarding (as the player moves through the level)
- Per-pixel collision detection (for slopes)

Once this is done, the 2D engine is pretty much ready. Then I can move on to some other mundane stuff.

Status report.

2004-12-28T08:10:00.000-08:00

I'm working frantically to get the new code base up and running.

- The background scroller engine is completed.
- The music sequencer is completed.
- The sound mixer is almost completed.
- The object engine, including animation and collision detection, is nowhere near completed.

Since the last update, I've released two new versions of my assembler+linker; the latest version was uploaded just a few minutes ago. With the new features and bug fixes, I'm ready to tackle the remaining parts of the game code.

Whoopteedoo.

2004-12-18T22:58:00.000-08:00

The cyclic pattern "write NES code - find assembler/linker limitation(s) - work on assembler/linker - write NES code - ..." reared its ugly head again. While the immediate outward effect is the halt of Neotoxin progress, in a longer perspective, it's certainly for the best. I've released a new version of my assembler/linker suite every three days since December 6. Each version has had significant new features and improvements, and looking back at version 1.0.2 three weeks ago, it's amazing how far it has progressed.

The new version, 1.4.0, is a real milestone, because it introduces constructs that enable the assembly code to communicate data mapping constraints to the linker. The lack of such functionality in earlier versions has been been a source of uneasy thoughts in the back of my head for the longest time, and I knew these limitations would strike me down sooner or later. Well, the time came, and thankfully, it could be dealt with.

With those challenges conquered, I'm ready to go back to NES coding full force. Unless something really, REALLY unforeseen happens (yeah right.. what're the odds of that?), the development won't suffer any long (as in several days) breaks from now on.

Well, I best get on with it.

The porting continues.

2004-12-13T23:54:00.000-08:00

In the last week, I've released a new version of the assembler, and have started porting my NES code to a more structured, less error-prone form. I'm constantly finding new features that would enhance the assembler, which means the porting and assembler development processes interleave eachother.

Even though it's a time-consuming process, I'm glad to see that the time I've put into the assembler is finally showing its worth. In fact, instead of directly porting my old code, I've started using the assembler's powerful constructs to write new and improved code. Besides, much of the Neotoxin code is old and could use some rethinking. For example, today I wrote a game object allocator/deallocator that runs in O(1) time, which will be a welcome replacement for the old O(N) implementation.

Stay tuned for the exciting sequel to this update, tentatively titled "The porting continues, part II: SnowBro goes mad".

Things picking up

2004-12-05T18:00:00.000-08:00

School's out... for Christmas. With exams out of the way, I finally have more time to work on my personal projects.

I've finished and publicly released a new version of my 6502 assembler/linker suite. It's available at http://www.stud.ntnu.no/~kenth/xorcyst for those interested. This is the tool I'll be using to code the future versions of Neotoxin. I've also released the source code to another NES homebrew game I made a couple of years ago, "BombSweeper".

Now it's time to tame the wild beast that is the Neotoxin code.

Some progress.

2004-12-02T13:48:00.000-08:00

I'm currently extending my 6502 assembler to support some useful stuff, mainly C-like structures, unions and enumerations. I'm sure you're all pleased to hear that this mundane work is almost done now, and a new version will be released shortly. More importantly, this will allow me to proceed to another mundane task: Porting the Neotoxin code base to my assembler, and structuring all the code. This step is quite crucial to ensure Neotoxin's future development, since the code has slowly gotten out of hand over the years. Entropy reduction is duly in order.

Once this is done, I will release the full Neotoxin source code. Then, work will commence on a brand new level editor. In parallel, the Neotoxin game engine will be tweaked and extended to support all major design elements.

My final exam this semester is on Saturday. Once that day has come and gone, development and updates should pick up quite a bit.

Neotoxin developer's blog opens

2004-11-14T10:26:00.000-08:00

This is my developer's blog for the free homebrew NES console game, Neotoxin.
Find out more about the game at http://neotoxin.emuchrist.org.
The project won't be going full force until school's out, sometime early December.
I plan to share some thoughts on the history of the game development, as well as the more recent happenings and future plans, and share advancements as they occur.
There will also be technical information here concerning the game's implementation.