This is interesting:
http://team-blur-games.com/overdose/about/
Especially:
Quote:
-Full SDK And Tool Set – OverDose is fully behind modifications and as such we have a complete toolset built from the ground up just for OverDose modders.
-Add-ons and game modifications support
• OverDose has an expanded movement system that’s like a buddy focussed Mirrors Edge. Players can: Go Prone, Move in Prone, Duck, Crawl, Slide, Walk, Run, Sprint, Jump, Long Jump (Leap), Dive and Swim.
• By yourself, players can mantle onto low objects, jump and pull yourself up onto higher objects, sprint and leap in one movement over shorter objects, hang off objects and hang/move off objects.
• With another player, players can reach even higher ledges by being helped up into higher places, either by pulling them up or giving them a boost.
• When you are down and awaiting a medic, you can crawl slowly, but can’t enter combat. If another team member is close by, then can drag you to safety much more quicker, and allow you to pull out your pistol to defend yourselves. Dragging a player to safety will allow a medic to revive them.
• Weapons not only have individual attachments, each with a pro-con, but also can jam in combat if not reloaded correctly.
-This now means that OverDose is totally open, totally moddable, and totally complete with its own mod tools, which include level compilers, map editors, font tools, custom HD .RoQ video compilers, texture compression tools, model format tools… Lets just say, a decent package of tools with a fully written SDK and developer wiki. So you don’t just get the game source code, you get the full shebang, everything. Of course media still belongs to OverDose, but the above should be great news to any mod people or budding game makers.
-Good news, every one! The OverDose level editor is nearly ready for use :D And while it wont support real time lighting quite yet (something you can do in real time in the engine anyway), it will support making the games maps and media without messing around with external editors, something that will ease the pain a lot of us face with OverDose mapping. Think of it as another step towards an awesome SDK, something we really feel like we have to push and get out there. Far, far too many PC games these days launch with no Mod tools at all, and to be quite honest with you that’s just not on in this day and age.
Their level editor is based off GTK Radiant.