A few weeks ago I talked about my work on the camera of my game Patin grappin.
The issue I was talking about was that this game uses a pointer (to be precise, an eye tracker) and any camera movement would make the world-position of the player's pointer move as well : the screen-position won't change but the pointer would not be pointing at the same object, for instance.
And Actually, while it was indeed a specific issue for the game I worked on, as it was an eye-tracker game. I realised I've encountered it before.
This design problem ruined a part of my experience when I was playing Mushroom11, a 2D exploration game with a weird gameplay.
In Mushroom11, you have to kill cells from your character, in order to make other cells grow at other sides of that thing you're playing. That's how you move and progress in the game.
So the game is working that way : you erase a part of your character to make it move. You can also split it in two part etc.
The game is really good and I think everyone should play it because it's really unique.
But there's situations in the game where you have to be really careful about not splitting your character in two. Phases where you're really thin and you need to extend yourself on the maximum you can. You're doing cleverfully thought cuts on your character to gain a few millimetters. Usually they're secondary path to get bonuses but it can be found in the main path.
Problem : the camera is not really controlled by the player. The camera always try to be in the best position to show the player what they need to see, while also following the player's movement, even if their character is splitted in two or three parts.
This camera is great most of the time, it's clear where you have to go, you're always on screen, in evidence, you're not losing yourself etc.
But when you're in one of those ''be careful not to split yourself'' phase, where you're extending your character, making it very thin, for exemple.. this happens :
All you want is to sculpt your character very carefully, step by step. And sudently. The camera move. Making your pointer move. Making your character split in two.
''Oh no.''
This is a problem that all game with moving camera and pointers (weather it's a mouse or a device like eye tracking) should be careful about.
Well.. Actually those games don't really exist. I mean.. they're not common, or their pointer is not as much as important as in Patin grappin or Mushroom11. I didn't find any other game that has this kind of relationship between camera and pointer.
Some Shoot them up use the mouse as a way to move your ship (I made a game like that ! ) but the camera will never make the position of your pointer change in the game world. Or it will but with a constant speed. In a shoot them up there's no huge difference between the enemies coming at you or the opposite situation : you're always in the same part of screen visually.
That being said, games that use the mouse as a pointer to determine where the character is gonna shoot can have this kind of problem too.
Take nuclear throne for instance. If you put your pointer far away, you can walk and shoot at basically the same angle for all time no matter where you walk to.
But if your pointer is closer from your character, you'll see that even though you're not moving your pointer, you're sometime changing the angle at which you're firing.
This wouldn't happen if the character was always at the center of the screen, if the character and the camera were attached to each other.
The game camera is focusing on the pointer more than on the character : if you move the pointer, the camera will move (while making sure the character is still on screen). It makes it so that if you want to see more of the field, you have to put your pointer away from your character. Most of the camera movement is because of that.
But the character also changes the camera : It's not just following the characterf... for game-feel reason, it waits a moment before catching the character back. This doesn't really matter of course, you will feel an inpact only if you're pointer is close from you AND you're moving right and left repetitively. Otherwise the effect will be negligible.
More concrete problem: sometimes, when approching the border of a level, your character screen-position will change.
You were shooting in right direction, didn't move your pointer and yet,you're firing bullets on your left.
Okay, okay. It doesn't really matter anyway because nuclear throne is not about precision that much : you fire at random angles and you can miss an enemy, you'll still have amos. But I think it can create some uncouncious player behaviors that you should be careful about, like ''staying immobile so that you'll know where you shoot all the time.", It may have happened to me sometimes, even though all the game is always telling the player to KEEP MOVING (and so having a player thinking "let's not move to be more precise" is not that good for vlambeer).
While writting this, though, I came accross this tweet by Mate Cziner. It's just a prototype but it was close enough to what I was talking about so I thought.. Why not talk about it here. I don't know anything about the game and may be wrong on what I think but let's do it.
This video is interresting because the game has a lot of quick movements, the character's screen-position is never the same, and it uses its pointer a lot. It could be a complete mess.
But when player actually uses the pointer, the time stops.
We thought about doing this in Patin grappin, but I thought the rythm would be ruined because of this. But actually we could have done this. It would just have change the game we were making.
We would have make a game intense rythm between action and pause. In MateCziner's prototype, the rythm caused by the slow down effect has now a great importance.
And you know what ? The game was already about that before the prototype started using a pointer and it's even more the case now. The game is not being slow down to solve the pointer problem. The pointer is used as a solution to other problems because it fits other parts of the design for the game.
Any solution to a game design problem will make other problems show up.
You have the right to change your game to fix an important design problem. In patin grappin, our game was all about the pointer, about the eye tracker. We needed it to work. Even if it meant not having the character on screen sometimes.
Pointer was not essencial in MateCziner's prototype, but by looking for solutions for other problems, the game eventually ended up having a pointer. There was probably 100 other solutions that didn't involve a pointer, but the pointer is good because it fits other parts of the games. The pointer is good because the game will not see the "pointer problem", it already solved it before it even showed up.
I'm glad about what we've done with Patin grappin. The pointer problem is not perfectly solved. But we didn't have to choose solutions that didn't fit our intentions. At some point, we were supposed to have a snapping mechanic that would have make it easier to point at objects.. But the game would not be about the eye tracker as much as it is now. At some point, we were supposed to only have objects on the ground, easy to look at, but the game wouldn't be about grappling as much as it is now.
I'm glad about what we've done with Patin grappin. I'm glad of what I understood about the careful use of pointers in videogames thanks to it and I'm glad if my experience can be helpful for others.