The thing about doors

Catalin from GrimTalin here, game director. I've been traumatized. In a game, I clicked on a door, but, to my folly, I was too close to it. As it opened, it hit me in the face and pushed me into the wall. I got stuck between door and wall, to spend eternity there - or until I reloaded the game.

In another game, I opened a door and it clipped through me. I nonchalantly walked out of it. That was a happy day. Other times, I was stuck inside it or the game physics popped me next to the door.

These are memories that have scarred my soul...

So, in The Crimson Maid, I took it upon myself to make less evil-inclined violent-prone doors. It wasn't that difficult, honestly. If we take into account the position of the player relative to the door, there are three scenarios: he is inside the door frame as the door closes, in the arc of the door as it opens or closes, or safely outside. Obviously, we don't have to do anything in third one.

If the player is in the frame as the door closes, first I make him take a step back, to a predefined safe position, so that the door doesn't hit him in the face, then I rotate the door. The player camera also lerps a bit downward, as if looking to the door handle, for a nice immersion effect. Detecting this situation is straightforward, using a box collider inside the door frame.

For the second scenario, when the player is going to be hit when the door rotates, a similar approach as before is applied. The main difference is that I use a capsule collider here to approximate the area covered by the rotating door.

Depending on which side of the door you are in both scenarios, you are moved to one of the two safe locations, one on each side. The positions and look angles are determined by the two helper arrows in my blueprint. The player movement is done by a simple timeline that interpolates between the current position and the safe one. Only when the player is repositioned can the door rotation start. If the player is already safe, then the door starts opening or closing immediately.

A quick and easy approach, easy to set up with a couple of colliders and two helper arrows. Everyone should do it. Or not, it's not that big a deal, but it makes things feels nice and polished. By the way, you can also catch an opening door mid-movement and close it right back - but enough flexing!

I hope you'll soon enjoy the untold wonder of opening and closing doors in The Crimson Maid. Please remember to wishlist and follow the game for more upcoming news!