Making and Working with Libraries in C++ (Multiple Projects in Visual Studio)
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- เผยแพร่เมื่อ 20 มิ.ย. 2024
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You forgot to turn off wire-frame display for the cactus.
I'm immediately subscribing, because of how clear the tutorial is
You're naturally gifted at walking people through potentially complex concepts rather effortlessly. I'll definitely be checking out more of your videos. Thanks man!
Your C++ series is really good. Thanks for making these as they're super helpful.
Dogecoin
This is exactly what I needed!
I would love to see a tutorial about proper use of namespaces in a large project and correct inclusion of header files (So that no circular dependencies can happen)
Great tutorial, short, direct and on point, well explaint for beginners, thank you very much!
Cool... You showed what exactly I was looking for... in detail and easy to understand...
I would like to see a video about exception handling in C++.
Tudor Lechintan he doesn't like exception handling, and I agree, exception handling is stupid.
we dont want to make exceptions xD
3 important commands:
-try
-throw
-catch
@@shpresimmuja467 why ? They can be very useful
Great stuff Cherno. Thanks!
Thank you, this was much easier than the MS guide for setting up a DLL. I couldn't get that to work. This guide is simpler. And note that it's also good for DLL's, not just static libraries!
This video explain its content as beautiful as a masterpiece. Thank you.
I spent hours trying to figure this out myself a few weeks ago. If I only knew that it was this simple...
This was really helpful.
I feel like I understand namespaces much better, too.
As always, great video!
Wow, you really saved me!!! Thanks SOOO much!
Absolutely amazing.
That's incredible
Awsome video! Thanks a lot man!
As usually amazing!
That was useful thanks !
Great video as always mate. It would be great if you could make a couple of videos regarding operator overloading as well as polymorphism.
Jose A he already did those
Your tutorials are really good. Thanks for this. Want to build a custom maths library for my 3d projects so I don't recopy every time. Thanks.
Awesome! Thanks.
Hey , A big fan of your great c++ sessions. can you please make one video on VSTest or native c++ unit testing in visual studio? This will be a great subject to make a video. Looking for hearing soon :)
Really helpful
God bless you mate!
I would like to see a video about C++ mobile development showing how to develop a very simple cross-plataform app. Maybe a video about "modern C++"? Another one about makefiles and/or CMake? I couldn't find good youtube videos about these topics, so... :)
Briliant video. Thanks..
Thanks!
Thanks for your video! Any chance to cover V-table in your future video? especially the internal behavior in memory. Also when talking about V-table it would also be nice to cover multi inheritance(evil diamond that people like to stay away) and the internal behavior. It is quite confusing but also interesting topic. Thanks again for your cool video! Hopefully could see more topics on C++ Optimization in future! (You probably have a lot to cover since this is c++.....Take your time!)
Thank you for video.
very helpful. thx
where i could find a cmake vesion of this?
Please make a video on Makefiles and CMake! Keep up the great work!
thank you
Like it, even though i knew all the stuff. But confirming it is kind of satisfying ;)
Thanks
You are "answers" to all of my questions))
I find it absolutely astonishing how vague and insanely complicated learning compiling with C is. You'd think having had over 45 years someone would have created a workflow that's actually readable. I can learn any programming language in 2-3 days but after 4 days now I'm still no where near closer to actually compiling a usable .lib file or where it actually goes in my project or anything. I think I'm actually more confused than helped by all the reading about Visual Studio I've done.
Great!
I tried separating my solution into an Engine and Game project like you showed in this video, however in my Engine project I am doing static linking to many third party libraries such as glew and glfw. This results in compiler errors in my Game project that says "cannot open source file "GL/glew.h" " etc... So do I have to do the static linking for all third party libraries again in the Game project (seems tedious) or is their a way to combine/merge them into the Engine.lib?
recursively watching all your videos
A similar tutorial for DLLs would be great. Maybe a C# Windows Forms App with C++ DLLs in the backend? :)
do audio next, what are good options for cross platform audio libraries and what techniques exist to manage audio effects and so on
After you make the reference to Engine, do you still need to keep the additional include directory that you added at 6:20?
Can you make a video on how to setup CUDA in VS 2017?
wonderful video!!!!! appreciation from China!!!😉
Yes it was veri helpful. Appreciation from India
Templates... Please make an in depth video on templates
Does the library have to be of the same language as the main project? If not, how can we use a library written in a different language?
Thanks for the tutorial. It clarified a few things for me.
Please make a detailed video on c++ templates
You are the best
8:29 That's interesting, I didn't know VS connected the libs from all your projects automatically. I thought you had to add them in the Linker under additional library Directories.
I follow your instruction and it works beautifully. However, when I add a header-only file to the static library project there are numerous errors - such as string not defined. How can I add an external header-only file to a static lib project?
All this process of defining source folder is done on Visual Studio program, it would be nice to see how it's done at the configuration file level so that the same can be done on other programs like de Visual Studio Code.
You talked about make a similar video but with a DLL ? Will you ever do it ?
I have a question: but what about ? Isn't that a library too? We have added the header file to cpp, but where is the library itself? Is it something that is dynamically linked like dlls? It seems to me that it is a sort of "special" link also because my program runs on another pc that does not have Visual Studio installed. I'm confused.
Hi Cherno,
First of all thank you very much for this series and everything you do here.
One question regarding the above.
If you would make a project to be build on someone else's computer, is all of this defined in a makefile?
How do you keep this consistency of linking the right static library and keeping absolute paths unchanged when you ship your project and aren't sure if the
customer or someone who works with you has VisualStudio?
Sorry if this is basic just need to wrap it all in my head.
Thank you in advance and best regards.
This is a really late reply, and probably not helpful anymore, but a couple of things to mention here.
For the "customer", they won't notice. These are static libraries here, which means that when the application gets compiled they essentially become a part of the executable. So, you just give the "customer" the executable file, and it should just work.
However, if you give the actual code to someone, things are a bit different. No, there is no makefile, because this is using the VC++ compiler, and all of these settings are stored inside the "vcxproj" file, so, if they have Visual Studio, and you give them the whole folder containing the "sln" file, all of the settings will transfer over. But, of course, they need Visual Studio. You could make a makefile yourself if you want.
Is this also the setup of the game engine series?
Thanks for your sharing. Would you introduce about some Design pattern in C++.
Dose the lib file have to be Inside the project solution for this to work.
I have tried creating static library in a separate project but carnt seem to get it to link.
I watched all three sequenced videos on linking in C++. While things are much more clear to me now, I was wondering if you can make a video about using CMake as well. I ask this because I tried linking Armadillo for example and could not solve the errors.
You uploaded this the 18th of October. It's the 29th today. Are there gonna be anymore videos in the series? or have you lost interest? Great series btw, I've learned SO MUCH. Thank you! :D
lol yes of course there will be more videos, it hasn't even been two weeks, relax :)
I'm relaxing. Sorry for hurrying you. I've just noticed that between each other vids there has been less than a week between them, sometime there were a new vid everyday. I was just curious. :'D
What about the libraries that the engine links into it? In my experimental project, even though I have my "engine" set up as a project reference in my "game", I still have to link my game against all the same external libraries that my engine links against, or I get a whole bunch of unresolved externals when I go to build my game, even though those externals are linked statically into the engine, and the engine is a static library.
The thing is, the engine.h file includes bunches of .h files in the engine which in turn include external library headers. So I guess to avoid this, I'd have to somehow not reference any external library headers in the engine headers that are included in the engine.h file, is that right? If you have public class members that are, return or take as parameters types that are defined in external libraries, what do you do? Define wrapper types for all those types? But the definitions for those types is going to have to be somewhere? The consumer of the library is going to have to know about them, so..? That doesn't solve the problem?
Is there no way to just tell the linker that all these external libraries are in engine.lib?
I guess to successfully wrap an external library into an internal library, you have to completely avoid exposing any of the wrapped libraries types. Which means your public interface can't use any of the types exported by that library. I suppose I know this already, but. I guess I was naively hoping some part of all the modern schiz would take care of this for me.
did you find a solution for this?
You have some guide to do all this from CMake?
Please cover exception handling or template classes and functions
I made it, half way of the series!
I did this with my project but i am having truble with my only nested namespace , it wont get recognized idk why :(
It's soo much different than the videos, no macros like #ifndef etc. @Cherno is that few thing we really need ? That's awesome. On Microsoft tutorial there is bunch of stuff. Why yours better ? Could you give me some explanation?
I keep thinking hes gonna hit his hand on that cactus with all that arm flailing body language
May i ask how is this better than just writing all the stuff (definitions and declarations) in a header file and then include it whenever we need it?
Do you have a video that does the same thing but create an import library and a DLL to install with the app?
I spent the first 10s trying to work out if that is an Ibanez RG and a Manson. 🤔
This is great and all but how do you go about this using a different IDE or even just a basic editor like Sublime Text, Notepad++ etc?
Wally Nut how do you even compile the code with simple text editors
Hi, sorry for the very late reply, I'm sure you'll have all figured it out by yourself by now, but maybe it will be useful for someone in the future.
I was in your same situation because I am on Ubuntu and I decided to go raw with just notepad and g++.
So I made some research and came up with something. This is for linux + notepad + g++ though, idk about windows, maybe there's something analogous:
First, I tried to replicate the filesystem like this:
engine/
|_ engine.h
|_ engine.cpp
game/
|_ application.cpp
I then positioned myself in the engine directory:
1 - I generated the object file from engine.cpp
> g++ -c engine.cpp
After this, engine.o file should pop up in the directory
2 - I created the library file from the object file using linux's command for creating static libraries, ar
> ar rsv engine.a engine.o
After this, engine.a file should pop up in the directory, which is the actual library file
3 - I then positioned myself in the game directory
> cd ../game
4 - Finally I compiled application.cpp linking it to the library. The parameters are:
-I : (capital i) the relative / absolute path for inclusion of the header file (similar to what he did around 6:06), in our case it's the engine directory
-L : the relative / absolute path to the library file (similar to what he did around 8:00), in our case it's the engine directory
-l : (lowercase L) the name of the library file, in our case it's engine.a
> g++ -I ../engine application.cpp -L ../engine -l:engine.a
After this, the executable a.out should pop up in the directory and do whatever is in the main() function
I used relative paths because I don't need it to be "a stable setting" since there's nothing automated in here.
Well don't I feel stupid, watch the whole video is the moral of this comment I guess...
thanks a lot man
cool
I feel like Neo downloading Kung Fu
How do you build cross platform?
I mean do you build Hazel exclusively for windows?
Do you not plan on having Linux (Android) support?
Because id like to know how you set up a cross platform project, especially cause of Android... (.so)
Do you use CMake?
you can do more object oriented things like namespaces, exception handling etc. Also you made a video on vectors, then u should also do other data structures specially those which are in the STL for c++. These are my 2 suggestions. And u r doing great so far and i follow u everywhere dude(not in real but virtually :p)....
Why did you include "Engine.h" in Engine.cpp? Shouldn't it work without that step as well?
Not exactly.
The compiler does not care about naming, naming is only useful for us people. So if you don't include Engine.h inside Engine.cpp, then the function declaration inside Engine.h could be treated as a completely different function from the one inside Engine.cpp.
For this reason some compilers even throw an error when you define a previously undeclared top level function in a program that's not meant to be executable.
That trick with add reference is nice
How do I share this library to others? I mean how can they use it in their projects? By sharing the Engine folder? Does this work even if they don't use Visual Studio to link or not even Windows?
What if I make a new solution where I also want to use a library/engine I made in a previous project?
Did you get an answer? I'm thinking about it too...
How would I do this using G++ or CMake?
So with let's say C#, it works just like this? Noice!
Um, no. For C#, you would have to use a DllImport on a DLL file, which is a DYNAMIC library, in this video, he describes how to use STATIC libraries... Static libraries don't and physically can't exist for C# since it's practically interpreted after it's compiled to IL.
So, technically, if you choose DLL in the list instead of LIB when he changed the project's properties, then added a C# project to the solution, set the build dependencies and set the library to copy to the C# bin directory, and used "DllImport" attributes within the C# code to access things in the DLL, then, yes, you could. Just not QUITE in the way he showed it.
Can you please make a video on how to do this with CMake?
How would I make the library work for Debug and Release mode?
implement some algorithms , specially those which involve pointers
Y'all can take this a step further and do it in cmake, it's objectively better for bigger projects and gives You more control.
What about header-only libs using cmake.
I got a little doubt.. Anyone can answer. Don't we want to use a class to write these Library functions? I know writing directly into namespace will work.. Does this have any drawbacks?..
IDK why I am Getting this error can anyone help me please!!
1>Application.obj : error LNK2019: unresolved external symbol "void __cdecl engine::PrintMessage(void)" (?PrintMessage@engine@@YAXXZ) referenced in function _main
1>C:\Dev\Cherno(C++)\Game\Debug\Game.exe : fatal error LNK1120: 1 unresolved externals
1>Done building project "Game.vcxproj" -- FAILED.
if you are having this error while you right click and building your application.cpp.... just Ctrl+F7 instead of right-click build
You can successfully build your Game project.
10:17 dont you have to recompile for the std::cin.get() to work?
Late answer but,
When he typed it and ran the program, it recompiled automatically then ran the instructions of the program
how can I include in game all the third party includes of Engine ?
I love you
which difference between obj and lib files?
how can I add header-only library in visual studio
I've made absolutely sure to copy everything you did (I just named the files differently), but I got an error.
*"unresolved external symbol "void __ cdedl Library::PrintMessage(void)" (?PrintMessage@Library@@YAXXZ) referenced in function _main""*
Library is the namesapce I used instead of Engine.
It seems to be saying that the main program can't find a definition for the function, even though I have one in the cpp for the library which I did include the header file for on both cpps.
If you are using VS2019 something that worked for me was after following all of the instructions in this video I had to go back to filter view, right click on the "references" filter then "add reference..." then a menu came up where I could toggle Engine on.
If you found a better solution I'd like to hear it.
Flashheart
THANKS! I was pulling my hair out!
I'm enraged, I wrote the solution 2 times.
Thank you, made a flash card out of it xD
I kept looking at the declaration and definition to see if I misspelled something, at the relative path too...
@@Wimachtendink where is refences? I'm not seeing anything. I don't see the button for filter view either.
@@smajin28 I'm sorry I really don't remember the context.
I think you can just go to the solution explorer window and right click "references" which should allow you to add references. But you probably want to gen comfortable with the Project Properties window which is project dropdown at the top bar, then the bottom option should be properties. From there you can include directories and libraries for the linker and stuff.
Sorry I'm not of more help but this was two years ago
Now , how to do it in dev c++?
what if dll, cou you give a tutorial about "Making and Working with dll in C++"
How does Application.cpp know i has to compile Engine.cpp as well? I mean only Engine.h is included in Application.cpp and not Engine.cpp, too.
Compiler