Metroid Prime hacking research

2015-05-26 12:13:10 pm

It just needs some forced dolphin anti-aliasing, but bloom as a way of making the room to appear bright, I have not seen that before

Aruki

2015-05-26 12:15:40 pm

they probably aren't intentionally being used for that, but with bloom, making the stuff under it brighter is unavoidable, so maybe they made the lightmaps a little darker to compensate?

Antidote

Edit history:

Antidote: 2015-05-26 08:44:19 pm

2015-05-26 08:43:05 pm

It's due in large part to how the bloom is implemented, Retro almost certainly had to make the lightmaps darker to compensate. Take a picture and overlay a 50% transparent version on itself. Repeat this several times, you'll notice that not only does it get blurrier it also gets brighter. Then take a darker version of the original image and multiply it with the resulting blurred texture, it gets even brighter, do it again, this time use additive. Suddenly it looks "proper". This technique must have taken some trial and error, and I definitely categorize it as a hack.

wowsers

2015-05-27 04:32:09 pm

So they basically hacked the already heavily modded version of unreal engine(I think I heard them using that?) to make a consistent bloom effect, that's even more impressive

Aruki

Edit history:

Aruki: 2015-05-27 05:11:26 pm

2015-05-27 05:09:28 pm

lol, no they did not use Unreal Engine. That rumor was started by a guy who noticed that they used the word "cooked" in the leaked editor screenshot, which is 100% solid undeniable proof. He backed this up by claiming that there were compiled UnrealScript files on the disc (there aren't) and that he found references to things like sounds and skeletal meshes, which are thing that have never been used by anything other than UnrealEngine ever. In fact that's a dead giveaway - if you are playing a game and it has sound, then you know it's an UnrealEngine game. So... basically he made this claim based on nothing and people believed it.

IIRC the files he thought were UnrealScript were AFSM files (which are finite state machines for defining AI behavior) and EVNT files (which just control events that happen during animation playback). It's a good example of jumping to conclusions.

Also as it's been pointed out by a bunch of others, the entire idea makes no sense. Retro would have had to license the engine years ahead of anyone else, and somehow find the time to heavily modify it to the point that they didn't even need to include a splash screen for it or even an acknowledgement somewhere that they used it, instead of just making their own engine.

"Metroid Prime runs on UE2!" was kind of an inside joke for us for a while because it's so ridiculous...

lol, no they did not use Unreal Engine. That rumor was started by a guy who noticed that they used the word "cooked" in the leaked editor screenshot, which is 100% solid undeniable proof. He backed this up by claiming that there were compiled UnrealScript files on the disc (there aren't) and that he found references to things like sounds and skeletal meshes, which are thing that have never been used by anything other than UnrealEngine ever. In fact that's a dead giveaway - if you are playing a game and it has sound, then you know it's an UnrealEngine game. So... basically he made this claim based on nothing and people believed it.

IIRC the files he thought were UnrealScript were AFSM files (which are finite state machines for defining AI behavior) and EVNT files (which just control events that happen during animation playback). It's a good example of jumping to conclusions.

Also as it's been pointed out by a bunch of others, the entire idea makes no sense. Retro would have had to license the engine years ahead of anyone else, and somehow find the time to heavily modify it to the point that they didn't even need to include a splash screen for it or even an acknowledgement somewhere that they used it, instead of just making their own engine.

"Metroid Prime runs on UE2!" was kind of an inside joke for us for a while because it's so ridiculous...

jackoalan

2015-05-28 05:26:01 am

I spent my whole day attempting to invert the tools that we use to extract audio from GameCube games.. Here is my first solid build of dspenc in action!

The quality is a bit hissy right now, need to do some more tweaking of the autocorrelator functions.

Try it out here:
https://github.com/jackoalan/gc-dspadpcm-encode

POSIX OSes only.. Sorry Windows users, haven't gotten around to porting it there yet.

wowsers

2015-05-28 01:14:16 pm

What exactly are you doing? Are you using imported audio and playing it back where other soundclips should be playing?

Aruki

2015-05-28 01:17:26 pm

He's encoding custom DSP files (custom music) from WAV files.

That is some really cool stuff Jack, nicely done!

wowsers

2015-05-28 01:22:53 pm

Oh, I was very confused for a moment where I didn't know if he just overlayed the audio on top of the video :P but it's impressive to invert a process so quickly even if the extracting is figured out.

jackoalan

2015-05-28 02:31:12 pm

Yea, it appears Nintendo's using an IEEE ADPCM predictor within the GameCube's DSP (audio processor). This allows audio to be compressed to 28.5% the original size (which is crucial when you consider the GameCube's tight memory limitations).

The correlator is the function in the encoder tool that analyses the input and produces a coefficient table to give the DSP a best-quality decompression strategy. Nintendo appears to be using a custom one, so that needs to be figured out to avoid the crunchy noise (reminiscent of a game from the 90s).

Jesse

2015-05-30 06:05:52 am

Might be fun to know, paper mario sticker star .csb files contain a string with "DEADBEEF". thats the same as the MREA header in hex.

DJGrenola

2015-05-30 07:38:15 am

that's been a common joke amongst developers wanting some sort of easily recognisable 32-bit value for decades, and there are many variants of it (0xBEEFCAFE, 0xDEEFACED etc. etc.) The fact that both games contain it isn't significant.

Aruki

2015-05-30 11:45:58 am

Soo uhh, while working with DKCR files I caught a minor bug in PakTool. Apparently world 6 (Cliffs) in DKCR has some really weird pak names. There are two paks labelled L03, and no L06, so it goes: L03 L03 L04 L05 L07. I guess when I was writing the pak lists (they weren't auto-generated) I just assumed they were in order, so PakTool looks for L03 L04 L05 L06 L07.

Anyway, here's a little update that fixes the problem. I also threw in a new pak list for Trilogy, so now you can auto-unpack all Trilogy paks as well. PakTool v1.01

jackoalan

2015-05-31 01:19:08 am

OK!! I've managed to solve the noise issues in the .dsp encoder and I've taken it a step further..

This is my fork of Audacity (a super handy full-blown audio editor).. It's everything the normal app has plus .dsp import/export capabilities!! It also automatically detects stereo file-pairs and visualizes the loop-region as a label track.

Only Windows and Linux are supported ATM.. Audacity currently uses some old frameworks that I can't build on the latest OS X.

Download it here:
https://github.com/jackoalan/audacity/releases/tag/Audacity-gc-dspadpcm-2.1.1

Let me know how it works!!

Aruki

2015-05-31 01:33:10 am

Very cool! Any chance this can be expanded for custom AGSCs?

jackoalan

2015-05-31 01:36:38 am

AGSCs would be tricky, since the SoundMacros would also need to be updated alongside the sample data (SoundMacros are event-heavy and well outside the scope of Audacity).. Although the actual sample format is identical, so this is a solid first-step to AGSC editing!

Aruki

2015-05-31 03:32:02 pm

Can Audacity load plugins? Maybe it could be implemented that way rather than a separate fork?

wowsers

2015-05-31 03:37:48 pm

yeah, it should be able too, I can't imagine all the LADSPA plugins on my pc is precompiled to the exact version I'm using

MrSinistar

2015-05-31 04:07:35 pm

Excellent work, Jack!!

Here's a video I did showing how I replaced the power beam sound effects in the Weapons.AGSC. As you can see in the video, I left the soundmacros alone so that the sounds still behave the same way in-game.

http://www.twitch.tv/lance_boyle/v/5369068

wowsers

2015-05-31 04:25:28 pm

very interesting video, was certainly helpful to get some ideas going on how to include sounds in my own project

MrSinistar

2015-05-31 05:37:25 pm

Thanks!

jackoalan

2015-06-01 02:55:39 am

I've updated the fork to import MP2 stereo .dsp files:
https://github.com/jackoalan/audacity/releases/tag/Audacity-gc-dspadpcm-2.1.1-2

Unfortunately, I can't make this a plugin library.. I need to use Audacity's internal ImportPlugin class to integrate the label track functionality. LADSPA, Nyquist and LV2 plugins are for implementing effects, not importers/exporters. The only other route is FFmpeg which introduces a whole slew of complexities and sacrifices the label track constructors.

This is the only function in all of Audacity that registers ImportPlugin factories:
https://github.com/jackoalan/audacity/blob/gc-dspadpcm/src/import/Import.cpp#L106

As you can see, Audacity makes no attempt to load external libraries whatsoever. I think the fork route is the cleanest, and git makes merging upstream commits a snap.

jackoalan

2015-06-01 07:09:22 am

YAY!! After rummaging through an old version of Xcode for the SDK I needed, I managed to make an OS X build of my Audacity fork:

Same download link:
https://github.com/jackoalan/audacity/releases/tag/Audacity-gc-dspadpcm-2.1.1-2

Baby Sheegoth

Edit history:

Baby Sheegoth: 2015-06-02 06:18:35 am

2015-06-02 06:10:14 am

Very simple, very cool concept thanks to you

jackoalan

Edit history:

jackoalan: 2015-06-02 02:30:28 pm

2015-06-02 02:28:35 pm

ooo! good idea!!

I think it's really interesting how that track loops, you don't even notice where it happens in-game. Yamamoto-San is a melodic genius!!

I noticed it cuts off abruptly at the loop point.. I need to experiment with the header-generation to solve that.