Super Fighting Robot!

megaman_ii_intro_by_yurell-d4rqbqs

Megaman!


 Yes, it is finally here! Megaman 2 PTC v1.0 is complete. Be warned. This is a big project, so it is going to have A LOT of QR codes. How many? 243 QR codes total, spanned across 6 files. Extensive testing was done to insure that this product is free from as many glitches, bugs, and errors as possible. Even with all our testing, it is still possible that a problem may be found. I will get a “README” file prepared as soon as possible for those that download the program, but do not know how to do things on it (such as the editor, or even certain in-game operations).

Grab the QR codes from the FILES section

Progress Report – Oct 5

So people are wondering where I am in terms of the project, since I continue to repeat myself, that I plan to get this done by the end of the year. That is still my goal, and that’ll only change if I run into a major snag from here to the end. Various parts of the development have ran into snags along its overall development, which I’ve ended up having to spend a lot more time reworking compared to others. As of right now, I’ve got the first 4 Wily bosses done. I’ll likely need to tweak them at some point, but they are working. The Mecha Dragon and Guts Tank had some snags, like needing auto scrolling and working with a platform like the tank has, but they’ve been dealt with. So what else do I have to do? Well, the last 2 remaining bosses, a teleport mechanic, the progress of working through Wily’s Castle (the stuff in between each level), and the little cutscene with Wily surrendering . I am hoping that I can design teleports to be used for custom levels, but we shall see. I’m still planning out how to get that implemented. Unfortunately, while the robot masters are available for use with custom levels, I have no plans for the Wily bosses to be available. Their mechanics are just too restrictive to allow it.

When testing the Wily bosses after getting the first 4 done, there was a screwup with the first Wily stage. The portion of the level where the Mecha Dragon would appear got cut off, so I had to extend that sublevel again. Currently the editor doesn’t clear the sublevel data from previous level in the main array I use, so when extending that last sublevel, it threw in the long stretch of the first sublevel that you start at. Seeing this, I wanted to see how the battle would be like, so I recorded it before I got to fixing it.

PTC – MML audio scripting with NES-like audio in mind

So I’ve had a request about how to make NES audio with PTC long ago, and I meant to make this tutorial back then, but things got in the way and whatnot, so no more interruptions!

NOTE: This is not a tutorial for how to make MML-scripted music. This is just going over how you can produce sounds like the NES uses.

Ok, first things first. In order to get NES-like music, we need to know what the NES used for making the sounds it does. The NES contains an APU (audio processing unit) that has 5 channels to it: two pulse wave generators (or square wave), a triangle wave, a noise generator, and a delta modulation channel for playing DPCM samples (similar to WAV samples). For what PTC comes with directly, we have 4 total pulse wave generators, and we have 2 noise generators. There is no triangle wave, but thankfully we can create one. With all the things we can do, we are left with a problem. We do not have the means to mimic the delta modulation channel. So I can only focus on the main 4 channels. There are other “additional channels” used in games like Castlevania 3j, but I won’t go over those. I figure once you understand the basics with the 4 channels, you may figure out how to handle those other ones yourselves.

First off is the pulse wave generators. PTC has access to these via the instruments from #144 to #150. However, the difference between these instruments is their duty cycles, which is the ratio between the pulse duration and the period within the oscillator. For those that don’t know what this all means, it simply means the sound will be different with each instrument. The NES pulse wave generators come with 4 different duty cycles, which are 12.5%, 25%, 50% and 75%. These match up with 4 of the 7 instruments we have available in sequential order; 144, 145, 147, and 149.

Next is the triangle wave. There is no instrument that replicates this channel in PTC, but thankfully, both the manual on the PTC website and the help menu in the program itself shows how you can make one under the BGMPRG section. It’s real simple. The cycle starts in the middle, goes diagonally upwards, then downwards to the opposite side, then back up into the middle. It will look like triangles. Here is the string I used for making it with BGMPRG….

DATA “000810182028303840485058606870787F787068605850484038302820181008”
DATA “00F8F0E8E0D8D0C7C0B8B0A8A098908880889098A0A8B0B8C0C8D0D8E0E8F0F8”

The last is the noise channel. While we have an instrument that takes on noise, there are some problems. The noise instrument in PTC and the noise channel on the NES are different. The DS/i creates what is known as white noise for its channel, which one could say is a randomly generated waveform of various sizes and lengths. The NES “noise” is much like pulse wave generator, but with a pseudo random sequence at 16 different frequencies with a length of about 32767 steps. In most cases, the noise channel we have is good enough. However, the NES noise has 2 modes. One that is the entire length of 32767 steps, and the other that is a segment of 93 steps of the entire length. We can generate an instrument (like what we did with the triangle wave) to mimic this mode, but we run into yet another problem. This 93 step sequence can be anywhere in the entire length, based on when this mode was activated, so the actual sound can vary from one time of play to another. For this second mode (which I used for Quickman’s stage theme), I made it into an instrument like I did for the triangle wave. It won’t mimic the variation you hear from the actual music, but it’s close enough. This is the string used for BGMPRG….

DATA “D03030D030D03030D0D03030D030D03030D030D0D03030D0D030303030D0D0D0”
DATA “303030D03030D03030D030D030D0D0D030D0D030D03030D0D030D03030D0D0D0”

Ok, so we have some information of the instruments we can use, but what about making NES-like music. Well, that is not something I can teach you as I am pretty much a noob on the subject. So how did I recreate the Megaman 2 music? Well, that’s where I go from looking like a professional to being the average joe. I had the tools to read the audio files and put them into a representation that I could map easily into PTC. Anyone recall how the music for Shovel Knight was made? For those that don’t, there is a program called Famitracker that aids in making NES music in a tracker-arrangement that you simply add notes, octave, volume, pitch, etc, and then you can export it to the actual NSF format so they can be played on NSF players.

But how does that help? Well, Famitracker itself doesn’t allow importing from NSF files, but people who got the source for Famitracker and NotSoFatso (a player for NSF formats) put them together to make an importer, called NSF Importer (you can find it by Googling). It allows you to import based on track. When you import, you’ll find various information per column. For square channels, the order is <note, octave, volume, pitch, and duty cycle>. The triangle channel’s order is <note, octave, -blank-, and pitch>. The triangle does not have volume adjustments, but it mutes via rest notes (which look like — in the note column).

The noise channel is a bit different in representation. It has 16 frequencies (range from 0 to 15, with 10 to 15 being A to F), so it mixes note and octave together. Other info is volume and mode. I had to figure out myself the note/octave for each frequency, and while far from perfect, what I list below is what I came up with (octave first, then note). While I only listed 12 matches, the latter 4 all sound about the same due to our ability to hear them. They do, however, sounds like they get quieter as you go for a higher frequency, so taking the ‘B’ frequency and changing the volume when plotting into PTC could help mimic them.

0 – O2 C, 1 – O2 A, 2 – O3 G#, 3 – O4 C#, 4 – O4 G, 5 – O5 D, 6 – O5 B, 7 – O6 D, 8- O6 F, 9 – O6 G, A – O6 A, B – O6 B

Well, that’s about all I can share, as the rest needs to simply be tinkered with by your own will, because sometimes you need to try them out yourself to understand them. I will note that NSF Importer imports the data at a rate of 60hz, so in 1sec’s worth of time, it will import/play 60 rows (I haven’t tried PAL music that operates at 50hz, but I assume that’ll be 50 rows per second). Because the tempo is always set to 150 (be sure to set this in PTC) and it reads at 60hz, I calculated that the smallest length for a note is a length of 96, so base your note plotting by that. Please don’t ask how I calculated it, because that was over 1.5 years ago and I completely forgot how I figured it out. As I said when I began this explanation, this is not a tutorial for how to make PTC MML music, so determining  the length is not part of this, but I will say that when you double a length value (like from A1 to A2), the actual play length is split in half, and likewise, splitting a length in half increases the play length by double. So if a note played for 2 rows in NSF Importer (one having the note itself and one without), the length value in PTC would be 48.

. A few notes about plotting into PTC. The square waves in NSF Importer are actually an octave off, so be sure to adjust that. Because the triangle wave is mostly for bass sounds, it’ll sound rather low on the DSi/3DS, so be sure to set the volume to as high as you can for that channel. As said before, importing operates at 60hz (or 50hz), but what was not said is that NES is not restricted to this speed. Various notes may turn on and off quicker than a frame, so NSF Importer will miss them.

Hope this helps.

Progress Report for July

The AI for all 8 Robot Masters, including their weapons, is finished, give or take some tweaking and additional bug testing. I have now moved on to developing the main portion of the game, making the interface for level selection and progress data. I still have the Wily bosses to work on, but that’ll be afterwards. Unlike the original, which used a password system, this port will use saving instead (up to 8 slots). Information for the save is displayed, which involves which weapons have been obtained, how many lives and e-tanks you have, and even the difficulty you chose to begin the game (and yes, there will be normal and hard modes). Unfortunately because of all the work I’ve done getting the game working under editor conditions, the original design for loading levels used by the past demos is broken, so that is going under repair procedures.

I know…I know….

Long episode of no updates. Completely my fault. So many things going on, and this project was a small portion of that. Sometimes when I have a breather, it ends up being more than a breather. A few things to note that has happened recently.

First was an attempt to make a converter that would take in NSF files (Nintendo Sound Format, basically, NES music/sfx) and convert them into MML structure. I originally was going to put together a small article that would describe the instruments used for replicating the NES audio used in Megaman 2 PTC and how I was able to export them decently accurate, but after diving into that, I learned that certain NES audio players had their sourcse available, so I thought that maybe I could save people the trouble of manually making their own music copies by creating this program and doing it automatically. The output seems to work decently, excluding various effects like pitch sweeps. Unfortunately, attempts to find the main loop points for each musical composition has been less than stellar, likely because the exportation method works off examining the state of the channels at a rate of 60 times per second when the music updates at a far more significant rate. Since the base of the exporter/player is made by someone else, I’d have to examine their work and see if I can retrieve the data a lot more often, or find another way to export the audio. This converter has been put on hold until further notice.

That is what I’ve spent most of my time on since this last update, though I have worked on MM2PTC here and there among other things. Various other distractions came about, such as family unexpectedly dropping by for the week from Idaho, Mario Kart 8, and just recently, E3. At the very least, I can say that all the Robot Master AI is completed, but only Bubbleman’s weapon AI has been programmed. There is one problem that I’m hoping I can get passed. When the program reaches a certain number of sprites on-screen (around 8-9, which include enemies, bullets, etc), the program begins to slow down. In most cases during the main game, that shouldn’t be too much of a problem. However, bosses like Heatman use so many individual sprites at one time (weapon fire mainly) that I can’t help but imagine that their fights will become slow. I’m devising a method that I hope will not only improve those scenarios, but general performance as well.

Computer, menus, extras and editor

Sorry for the gap in updates. After dealing with the HDD crash mention in my last post, it became apparent that I was in need of upgrading my computer. So, I did quite a bit of researching as to what I could use/need, and with money saved up (along with my tax return), I purchased items and built a new computer. This dug into my time that I usually spend with this project, but I have done some work nonetheless. No more “terminal” interface appearance. Now the menu system has been implemented for going from one part the program to another. With that, extras have been included, such as the Audio Player and even the Credits. Using methods meant for the menus, I am also incorporating them into the editor so the method of displaying information doesn’t look so plain.

The robot master AI has been put on hold for the moment because I have to decide how I am to deal with them in custom rooms, much in the same way I had to alter/add AI routines for some enemies because they can be placed anywhere that are not normally allowed in the original game.

A December Update

Sorry for the lack of updates. Been going against a bunch of hurdles with the program, but most have been dealt with. As of right now, all enemies and sub-bosses have been completed with their AI improved and adjusted. Dealing with the sub-bosses was a bit of a chore because they didn’t deal with just sprites, but also messed with the background as part of their visuals. Also, because of being able to place them anywhere with the editor, I also had to make numerous code adjustments (to prevent overlapping) as well as numerous palette execution changes with regard to them because of how they may use palette animations (so by doing a palette animation to one, it would have affected all others of the same type in visual range).

I’ve also been refining the code that deals with transition data (that allows moving from one sub level to the next) as I added gate placements. This did cause me to require changing map collision data so now, there will be a 1 tile invisible wall on either side. While this makes Megaman react correctly like the original did in this instance, it will affect how enemies will react to this wall, which are supposed to act differently. Shouldn’t cause much of a problem though. The transitions can either be activated by touching any open portion of the sides, or just one open portion. The gates can be placed on any open section on the left/right sides. The original game does not have gates leading up/down, but I wouldn’t cross that off the list just yet. It won’t be a focus atm.

Before I begin work on the bosses, I will be going through a stabilization session, to ensure that what can be created with the editor would not result in errors that stops the program.

Still around…

I’ve been sick for the past couple of days, so I’ll make this brief. Been working on numerous things, most involving the remaining regular entity/enemy AI, so the blocks that phase in and out, lazer beams and even lighting changes in Quickman’s stage are all functioning (the lighting, however, restricted to that stage). I have yet to begin AI work on the sub-bosses and regular bosses. Also found numerous bugs in the editor which began to pop up when I began working on the Entity subcategory.

Demo v0.2 available now!

   (Demo should run with all versions of Petit Computer now, but errors may crop up. If the QR code list still reads 99 on each code, then refresh the page. It should show 98 instead)

(click the image to go straight to the codes)

It is official. Demo #2, almost 11 months in the making after the first demo was released, is now available, either by the image, or through the website menu above. A lot of work was put into this version. The code was redone almost completely, resulting in more flexibility, and speed is very much improved when numerous objects are on the screen. All game assets are compressed and packed into GRPs that are packaged into the program file, so all the codes are set for a single file, unlike the last demo that had numerous files scattered all over.

Be aware that this demo contains custom-made levels. Because of this, the difficulty of each of them will vary, with some parts too easy, and some parts too hard. I did extensive testing to ensure that the areas are passable, but that will be up to you all to decide. The total QR code count is a whopping 98 codes, and this doesn’t even contain all the game assets. I’ve had requests to make the demo available in other ways, so not only can you scan the codes in from the website, but the codes themselves are available via TAR.GZ format, and even the PTC file that contains the demo is also available (for those that have trouble with scanning the low-error codes) so you can make the codes yourself at the Petit Computer website.

Other than the custom-made levels and major rewriting of the code, the demo contains the following that were not present in the previous version…

  • More enemies.
  • Health bar (yay!)
  • Enemies drop items.
  • Health capsules that actually work.
  • Movement is more in-line with how Megaman should move.
  • Death animation and checkpoint refreshing implemented.
  • Runs smoother (just had to restate that again).
  • Intro scene