RespawnBsp History & Progress Reports

[snake-biscuits]

Documenting the latest theories and experiments reverse engineering the RespawnBsp format(s)

[snake-biscuits]

I'm afraid it's been... 9 years...

Timeline of Titanfall modding

2014

January

Before Titanfall's retail release, but after the public betas and tech tests, Cra0kalo makes plans to create modding tools¹

February

Cra0kalo reverses Respawn's .vpk archive format and publicly releases tools (closed source) to extract their files²

March

By early March .bsp files had been dug into, with strings identifying multiple lump names found in bin/x64_retail/bsppack.dll
ata4 starts work on bringing Titanfall "support" to bspsrc, a popular Source Engine map decompiler³

August

Cra0kalo theorises (incorrectly) that the map format hasn't changed much since Portal 2⁴

2016

Titanfall 2 releases

2017

May

The Titanfall 2 single-player only Icepick mod launcher enters development⁵

2020

March

snake-biscuits is killed by a CS:GO hacker with a YouTube URL for a name; they follow this link, and find cra0's blog
Discovering VPK Tool, they add mods/titanfall2.py to bsp_tool⁶

Various projects to create modded clients for Titanfall: Online, Titanfall 2 & Apex Legends cross paths across multiple Discord servers
snake-biscuits gets involved, trying to port maps between all 3 games

2021

August

The Apex Legends mod client R5Reloaded releases to the public⁷

December

BobTheBob releases v1.0.0 of the Titanfall 2 Northstar client publically, just in time for Christmas⁸

2022

April

F1F7Y begins work on MRVN-Radiant, a fork of the NetRadiant-custom level editing software⁹

June

barnabwhy releases their open source VPK tool: TFVPKTool¹⁰ (Cra0's tool was closed source)
This forms the backend for HarmonyVPKTool

By the end of the year MRVN-Radiant is compiling basic maps for all 3 games
Momentum researching the .bsp format continues to grow exponentially, with better and better tools helping us to experiment & learn

2023

Team Floppa Online real?

Footnotes

1. 2014, Jan 3 - Twitter: Cra0kalo vows to create modding tools ↩

2. 2014, Feb 15 - Cra0 Blog: Cra0kalo releases VPK Tool ↩

3. 2014, Mar 4 - GitHub (ata4/bspsrc): working begins on Titanfall support ↩

4. 2014, Aug 3 - Cra0 Blog: Cra0kalo talks about .bsp & xbox360 .bpk ↩

5. 2017, May 10 - GitHub (Titanfall-Mods/Titanfall-2-Icepick) Initial Commit ↩

6. 2020, Mar 1 - GitHub (snake-biscuits/bsp_tool): research begins on Titanfall 2 ↩

7. 2021, Aug 14 - GitHub (Mauler125/r5sdk): R5Reloaded v1.4.0 ↩

8. 2021, Dec 24 - GitHub (R2Northstar/Northstar): Northstar v1.0.0 ↩

9. 2022, Apr 22 - GitHub (MRVN-Radiant/MRVN-Radiant): Initial Commit ↩

10. 2022, Jun 30 - GitHub (barnabwhy/TFVPKTool): Initial Commit ↩

[snake-biscuits]

2017 - May: The Titanfall 2 single-player only Icepick mod launcher enters development

Icepick is significant because it served as a base / inspiration for Northstar
The Icepick devs also managed to create a python script for converting Titanfall 2 .bsp files into .obj models
Likely reversed from a function present in Titanfall 2 itself, this code formed the bedrock of bsp_tool research into Titanfall 2 maps

[snake-biscuits]

Preserving some screencaps of citations just in case Twitter totally collapses

[snake-biscuits]

In 2023, we have a pretty firm grasp on how Respawn Source renders .bsp files
We're really starting to dig into the Visibility (culling, occlusion, depth sorting etc.) systems, as well as physics

Map decompilers are good enough to be educational, and we have some understanding of how to get lighting in-game

A lot of our development has been focused on Titanfall 2, but we can test maps on all 3 games (including the currently private TF:O client)
We've ported TF:O's mp_box to Titanfall 2 & helped the R5Reloaded team create World's Edge: After Dark

There's a lot of big ideas ahead, but we're still slowly building up the tools
Very happy to be at the point where progress is something that can be expressed in screenshots and videos
mp_firing_range_inbounds_grenade_crash.webm

[snake-biscuits]

Currently I'm working on mimicking the way meshes are sorted in official maps (transparency, decals, & skybox mesh groups)
This is happening in my fork of MRVN-Radiant

I also want to document & add support for all the various entities available to mappers, over at MRVN-entities
As that comes along I'll be developing various sample maps to demonstrate how to use them for new mappers in MRVN-Resource-Pack

We recently got a bit of a breakthrough with rexx finding a way to get the member names of various .bsp structs
Still haven't fully explored the new information this brings, like how different lumps index one another

Meanwhile collision research has gotten so fine we're reverse engineering bitfields & flags

[snake-biscuits]

Mesh sorting results are unclear atm.
I broke ObjReferences indices (VIS)
Titanfall 2 has no 2D skybox images
sky_camera appears to do nothing
TF:O maps don’t cache materials for some reason

[snake-biscuits]

In other news, "coverage" (% of lumps understood, by number of attributes called unknown) of RespawnBsp is very high
Titanfall is now the 3rd best mapped branch script, just below Quake 1 & 3
Titanfall 2 is 5th, just ahead of GoldSrc
Apex Legends in at around number 23, just behind most Source Engine variants
Somehow Quake 2 is behind Apex, even though Q2's source code has be public for ~25 years

Developer	Branch	Coverage
id_software	quake3	100.00
id_software	quake	97.67
respawn	titanfall	92.92
id_software	qfusion	88.89
respawn	titanfall2	87.27
valve	goldsrc	86.00
valve	orange_box	75.34
valve	source	73.28
respawn	apex_legends	69.28
id_software	quake2	67.89

(taken from docs/supported/coverage.sc)

[snake-biscuits]

The coverage percentage isn't the best way of conveying how far we've come imo, but it does the job.
Kinda funny that the mostly open source Quake, GoldSrc & Source Engines aren't 100% mapped yet

[snake-biscuits]

Still, 70% and above is really good. almost all branch scripts below are obscure w/ either wierd 3rd party tools or no tools at all
Though everything below 50% has official tools (if you count all 3 mohaa branch scripts as the same game)

CSO2 is in the unenviable spot of 50% support with very limited tools, and not enough time to really work on it
And Vindictus is at ~71%, but I have yet to find a client to test custom maps (though one may exist)

[snake-biscuits]

Physics Reversing

• `respawn.titanfall.Brush`'s final unknown member #81
• TriColl #106
• Apex Legends `BVHLeafData` #111

[snake-biscuits]

#81 in particular documents methodology pretty well (theory crafting & bulk testing)

See the wiki page on spelunking for more notes on research methodology

[snake-biscuits]

Lighting Reversing

• `UNKNOWN_97` might be RTL lightmap data #122
• Titanfall Engine Lighting System #176
• Titanfall Engine lightmaps #89

[snake-biscuits]

Got a big burst of reversing work done on WaterBodies recently

• Apex Legends Water Bodies system #166

tl;dr it's the lumps involved in rendering the ocean on Habitat & Storm Point