what are capabilities and limitations of unreal engine blueprint

Blueprint is coding so the idea that it's "making games without coding" is trivially false. It's more accessible, and thus easier to get into, but - at some point - the presentation method will limit the ability to manage a complex code base to the point it's easier to write more traditional code.

Blueprint is Turing complete and has, AFAIK, access to everything within the Engine that you can access from C++, so I don't think there's anything of consequence you can't do within it. The question is performance and there, figures of about 10x slower are kicked around. There will be some applications for which that is an issue; but I don't think there are many.

10 minutes ago, Irusan, son of Arusan said:

Blueprint is coding

I don't agree with this as per the definition...

coding - write code for (a computer program)

but I see that argument all the time. Please tell me how blueprints is coding? I'm not trying to be funny or difficult, I really want to know why this notion of coding not using code is a thing.

5 minutes ago, fleabay said:

I don't agree with this as per the definition...

coding - write code for (a computer program)

But that's exactly what Blueprint is. The computer program is running on a highly specialised operating system (Unreal) and chooses an unusual presentation but there is an exact one-to-one match between everything Blueprint does and how you could represent that in a flat text file. You'd loose the fancy 2d layout and connecting lines and stuff but these have no functional impact, any more than syntax colouring or font choice do in C++ code. In fact, you could go the other way, if you really wanted and write a system that let you compose C++ in a fancy 2d environment with lines connecting stuff.

Programming is the process of giving a computer sequential instructions in a formalised fashion. That's what C++ does. It's what assembly does. It's what Python does. It's what Blueprints does. Blueprints feels different because it is presented in an unusual fashion, but it's not fundamentally different.

1 hour ago, Irusan, son of Arusan said:

Blueprint is coding so the idea that it's "making games without coding" is trivially false. It's more accessible, and thus easier to get into, but - at some point - the presentation method will limit the ability to manage a complex code base to the point it's easier to write more traditional code.

Blueprint is Turing complete and has, AFAIK, access to everything within the Engine that you can access from C++, so I don't think there's anything of consequence you can't do within it. The question is performance and there, figures of about 10x slower are kicked around. There will be some applications for which that is an issue; but I don't think there are many.

the problem is unreal blueprint is designed to make some predefined game mechanics like tanks vehicles character animations and... in my game maybe i need to work with xml or json. in my game maybe i need special scenario of multiplayer and work with special type of multiplayer system. maybe i needto work with on certain algorithm or game mechanic. can blueprint support all of that? blueprint nodes are just some predefined functions. what about new stuff????

1 hour ago, Irusan, son of Arusan said:

The question is performance and there, figures of about 10x slower are kicked around

Exactly,

I've toyed around a bit with Unreal and I can easily say that prototyping is where blueprints shine.

But as soon as you want to optimize, then you've got to dive right into C++.

I would also add that a typical Unreal game should have both blueprints and scripts, as blueprints are generally faster to develop than scripts are.

14 hours ago, Irusan, son of Arusan said:

you could go the other way, if you really wanted and write a system that let you compose C++ in a fancy 2d environment

Someone did for C# something similar that was inspired by Unreal Engine name Netprints

I think someone with some time would be able to port this into Unity and write some kind of C# code generator for it