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Will KS campaign (or something like that) help to bring Vulkan API to Grim Dawn? Maybe also collect money for true multicore support too? 
Directx11 support would be better. Both directx12 and vulkan are buggy and mess rite now, they need a lot of updates.
Directx11 is not he API we are looking for. It’s not low-level (so we will not have performance boost), and it’s not multiplatform. GD will not benefit from DX11.
Vulkan have a great future, some games already benefits from it’s implementation and some emulators (PPSSPP, Dolphin for example).
GD is optimized poorly. Probably it is lower than average when it comes to “optimization quality”. What you say seems impossible because Crate is a small team + Vulkan transition needs “starting from stractch of game engine” which can take a year^^. They already use an old engine (TQ) and game took a lot of time. In order to fasten and optimize this game, fastest and cheapest option is directx11 which now they can optimize their old engine.
Vulkan for cross-plarform probably makes no sense because I expect GD to also use the other DirectX parts, which means it still would not be portable.
Not even sure DX12 would be worthwhile, which leaves better multi-processor/core support, which most likely is the only relevant performance problem we have anyway (or at least no other improvements matter until this one is addressed).
It is far more feasible for Crate’s next game to be Vulkanised.
And it should be. Right now I only use Windows for gaming and I imagine many others as well. It’s high time we end that horrible legacy of the 20th Century called Microsoft.
Unfortunately it ain’t gonna happen any time soon.