I have no problems using my ps4 controller in other games, though its worth mentioning that those games are played through steam, and steam has its own emulator for games.

Games like the Witcher 3 and Hitman2016 have built in ps4 controller support, and honestly it still baffles me that its not a standard for game development to support every type of controllers on PC, especially the main ones, Xbox and PS.

I want PS4 controller suport for this game.

Actually they don't have PS4 Controller support, they do use the steam API for controller support that's why they support the PS4 controller when the game is run through the steam client. The DRM-Free versions don't have access to that API unless you run steam and add the game to the steam menu. To avoid that you can use a third party tool/driver DS4Windows to emulate a XB360 controller via windows for your PS4 controller.

As far as I know Witcher 3 and Hitman2016 do have ps4 controller suport, indicated by the changed button prompts in the game, and Witcher 3 I played here on GOG, and works just fine with my ps4 controller, without any additional programs like DS4Windows.

I am able to play Witcher 3 and Hellblade Senuas Sacrifice on gog with my ps4 controller without using any additonal programs.

Of course it would be nice if this would be possible with other games on gog too. At least with new games and games which are promising controller support in the product informations.

Hmm, I don't know about Hellblade, but Witcher 3 most definitely didn't natively work with my PS4 controller. I just tried it a few hours ago and without DS4Windows it didn't see any controller. Now just for the record, I didn't try it plugged in wired, I only connect the DS4 controller wireless via bluetooth, and without the galaxy client running.

DS4Windows has long been dead... the same guy has an actively developed replacement app called Input Mapper ... but better yet, skip all that and get an 8BitDo Adapter and use your PS4 controller (or even a Switch Pro controller) in any game in Windows with simple plug and play... but ultimately, the best way to use a PS4 controller on Windows is running the game through Steam cause it's the only way to get access to the gyro, touch pad, etc.

And The Witcher 3 GOG build works natively with a PS4 controller, but only if you're using the official Sony dongle... I can verify that, cause I have one... get the in-game PS4 icons and all and no other software running besides the game