I've attempted this but its honestly way too much into mechanics that will take a lot of time away from your game designing. I still poke at this system once and a while, however it is very flawed as in Game Guru it is very difficult to get the 2D mouse pointer to interact exactly with the 3D plane points when you start messing about with different camera angles.
So while its possible, its a lot of work. You can however use 3rd person mode and just put the camera distance far enough away. But if you want the same controls as Diablo that are primarily with the mouse you are going to find yourself with a lot of headaches. Especially when testing in different resolutions. Game Guru uses a percentage-of-screen system instead of pixels.
The tests below I have do not use the player at all. Not even the 3rd person controller. Its a complete override and its still very glitchy and unpredictable at present:
It has a working 2D mouse that I can use to interact with 2D sprites such as inventory, status screen and item belt. However the interactions with the map with the cursor dont work well at all and start to warp when you position the pointer near the top or sides of the screen. I am just not that good at math to create a formula to create the proper calculations of the warped numbers in those regions of the screen.
I could however make it so the player moves in the direction of the 3D mouse position. But to get him to move with AI to the exact position and around obstacles is just too hard without a better 2d to 3d position support. There are some people testing with this on the forums, however mostly in first person.
For me to advance that the system any further, I'd need some more internal support with the engine. Doing work arounds has taken away a lot from of my life experiences lol as I find myself putting in weeks to months of work, just to make something incredibly simple to do in Unity, to work barely in GG. The engine just isn't designed for this style of play (yet).
HOWEVER!
Now here is some exciting news for you. As I mentioned before you could use the 3rd person and just extend the camera distance out. It would require no programming to do this. However you wont get those awesome 2d to 3d mouse interactions.
Some community examples of this below:
Its important to note that (i dont think) Game Guru doesn't support swapping of different weapons in 3rd person. So... having weapon pick ups would be completely useless. This might change in future versions of GG.
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