Someone on Reddit claims that the new DOTA2 mod tools is actually the Source 2
Everything in this package is a new game. It's all the Dota assets and code ported over to Source 2. That's why Hammer is different. That's why the console is different.
Guys. Valve just soft launched the entire Source 2 engine.
EDIT: Because people are asking for proof.
Everything that would share a name with Source is named '...2'. That's 'engine2.dll', 'vconsole2.exe', 'vphysics2.dll'.
When you go to open a map in Hammer, it asks for .vmap files. One of the other options is '.vmf (Source 1.0)' files.
The fucking console is redone.
There is a new Key-Value like format (that i'm gonna call KV2). It is type safe. It looks like this: http://pastebin.com/RVQtkv1j. EDIT: Looks like my name isn't going to stick. The engine calls them 'Schema Files', written by CSchemaTextWriter.
EDIT2 (Probably the strongest evidence): That script also allows for different dlls to load and render different assets (vmaps are rendered by worldrenderer.dll, etc). This is a completely new architecture from Valves previous system. This bit alone would indicate a significant amount of engine work has been done to split these bits out of the engine and into their own libraries. That means the engine is also completely plug-and-play with new engine level components if valve creates them for different games. This is pretty freaking huge.
EDIT3: lol, source2 apparently support fax machines.
EDIT4: from /u/nellody: https://developer.valvesoftware.com/w/images/3/35/Tileset_new_outliner.png notice the 'source2' in the path.
EDIT: the general consensus around the source reverse engineering community is that this is really source 2.
http://www.reddit.com/r/DotA2/comments/2cv5os/so_the_workshop_tools_isnt_just_a_modding/
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