Thanks for watching guys, hope you enjoyed the video! Next episode is already available for Patrons at www.patreon.com/posts/23365701

You may have two problems when following this episode: 1. lots of unresolved external symbols 2. unresolved external symbols DwmExtendFrameIntoClientArea 1. For the first problem, you may notice that in GLFW project setting, go to C/C++ -> Code Generation, on the right hand side, the runtime library is Multi-threaded DLL (/MD), that means when compile this project, GLFW will use C++ dynamic library. And in the Hazel project setting, the runtime library however is Multi-threaded (/MT), that means when compile this project, Hazel will use static links of C++ runtime. Now we can have 4 combinations, and all of them are valid except GLFW use (/MD) and Hazel use (/MT). Therefore, you can have GLFW use (/MD) and Hazel use (/MD), or GLFW use (/MT) and Hazel use (/MD), or GLFW use (/MT) and Hazel use (/MT) Here, it is better to set this options in premake5.lua file, however I didn't find any method to change that setting. You can set it in Visual studio directly. And don't forget to set it each time after you regenerate the solution .sln file. 2. For the second problem, I guess that the new version of GLFW use this new function, and this function is in dwmapi.lib. Therefore, add this dependency into premake5.lua. links { "GLFW", "opengl32.lib", "dwmapi.lib" } And regenerate the solution. Don't forget to change the C++ runtime setting.

You inadvertently started a tabs vs spaces war.

Thanks! I finally got it to work after I changed GLFW project properties -> C/C++ -> Code Generation ->Runtime Library -> Multi-threaded (/MT)

I feel like this new way of going over the game engine is glossing over huge steps and being less efficient than before. I think a better method would be a video on heavy concepts such as windowing, event system, etc, be live coding. Then do a smaller 5-15minute video of review over that episode where you go over the changes you made to the code after reviewing it yourself (since not everything can be caught coding live), that follows the format you're doing now. When you did live coding episodes you explained why you did what you did where as this feels like a sparks note of the code, and doesn't explain much.

I had a hard time following this one as i'm coding along and not just getting the resource from your git repos. I managed to make it work in the end and i have learn a lot of things so cheers as always.

If anyone is having issues with unresolved externals related to glfw3 when building, I found the issue to be in properties -> C/C++ -> Code Generation -> Runtime library. Switching it from Multi-threaded debug (/MTd) to Multithreaded DLL(/MD) or Multithreaded Debug DLL (/MDd) did the trick. To make the premake file do what you want, they keywords are staticruntime and runtime. for /MD you want staticruntime "off" and runtime "Release", and for /MDd you want staticruntime "off" and runtime "Debug". You may also need to get rid of any buildoptions that override this (I had buildoptions "/MT" which overrode /MD). Hopefully this saves someone some time :)

Hey Cherno. I understand why you made the switch to prewriting the code, and just reviewing it, but this way isn't really teaching. I really preferred the other style. I know it is probably more difficult to play to write everything, but I learn by coding along side you. I really miss the old format.

Hey Cherno, ,You are doing amazing stuff please keep it up!

this is better than my school education you are a good man. thank you

My English is not very good, so I translate part of your words into a dictionary, write out unfamiliar words and teach them. I really want to understand everything that you say by ear. You're the best, thanks for your videos. P.S. This post is written in google translator

Hey! I just wanted to make a comment about the teaching style and your comments at the beginning of the video. I am a Computer Science teacher who has taught courses on game programming / engines, and have spent a lot of time talking to other faculty members / industry programmers about how to teach game programming. I have found that for students / audiences with zero initial knowledge, it is much better to use a top-down approach then bottom-up when teaching game engine programming. Bottom up like you are doing is great for the more technically minded audience who already has some experience, because they can greater appreciate the context for why you are doing what you are doing. Despite your explanations, its really only something you can appreciate after you've already made a game and done a bunch of things wrong. For completely new students, I greatly prefer top-down. By doing things top-down, you can start with a very simple game example with controls, drawing the the screen, and get the students hooked on having an actual very simple game up and running. Now that they have this experience, you can start abstracting away parts of the engine into the systems that you are talking about here in your video series. Once they have dealt with things like hard-coded input handling, or tying their drawing system to a specific API, they can really start to appreciate Event systems or window abstractions. So I understand why you are teaching it this way, but just realize that you are probably going to either a) lose the interest of novice programmers, or b) only start to get a lot of views after the entire series has been completed. Please don't take this as criticism, I'm a huge fan of the series and don't want you to change anything. I was just giving another explanation of why you might find viewership not being as high as you'd like so far. Please keep up the great tutorials! I've pointed some students to your C++ videos in the past and they're a great resource. One other small thing: You probably don't need to spent 2-3 minutes at the beginning of each video apologizing for the previous video or explaining the context of this video within the series. Once the series is completed and people binge-watch the videos that will pretty much just be dead air. So while you're explaining it now and it makes sense, later on it might not be worth having those segments in the video. I think it might be a better idea to just get straight to the content of the video, and then maybe release a separate longer video explaining all of the other non-programming related things.

Just a small note: Ctrl + H (aka. find&replace) could be really helpful for changing tabs/spaces rather than finding them one-by-one.

really self aware move. my two cents: i enjoy all the of the content and i'd be most excited to follow the logical structure for a game engine... im a beginner and doing foundation data structure stuff before i really move onto this though. realy brilliant videos man, youre a great teacher

I had to go through all the videos till now twice to understand what was going on here. I don't think there is any such c++ intensive project on whole of KZfaq which not only teaches c++ but also helps visualize it. All hail @TheCherno

Hey there, awesome video as always :) A small request thou - could you show the diff changes at the start of the video?

15:35 This kind of code design is actually described by a design pattern named Abstract Factory for the once who are interested :D

Thanks as always for uploading Cherno, I love the series! Am I right in saying that member functions defined within a class definition don't need to be explicitly inlined? For example, WindowsWindow::GetWidth(). Not an issue obviously I'm just wondering whether you do that for increased clarity. Thanks again, can't wait for next episode!

Neat stuff!

Hey, I have a question. What is your opinion on SDL? It's my library of choice when it comes to making my game engine while watching this.

in the beginning I found premake quite difficult, but it's actually easier and more convenient to use than the visual studio property pages. Microsoft has outdone itself on that one.

Don't use the most updated GLFW in Cherno's repository. That would give you error which I don't remember anymore. It's a quite long name and no where you can find help online. Instead go to the corresponding commit of this video "Added Window class and GLFW'" and click 'GLFW' in left side panel, then on the right side large panel you can find 'Submodule GLFW added at b4b431'. Click 'b4b431' and there is the right GLFW you need to finish this video. I am totally a starter so I can't find out what is the essential difference between this GLFW and the most updated GLFW in Cherno's repository, but any way, this solved my problem. Oh and don't forgest to change the 'systemversion "10.0.17134.0" ' to 'latest'( or whatever your Visual Studio have) sin premake5.luna file which Cherno mentioned in this video.

I'm a huge fan of this series and the new format! The series is all about how game engines are made seriously instead of what I feel like are kind of easier versions elsewhere on the internet. The new format is like a code review and helps the understanding so much!

It's a little hard to follow what is actually included in a file, because often the include is not explicitley in the file but in the pch or other files that include the current file, or is that just me ?

Line 22 here 12:00 *buildoptions { "-std=c11", "-lgdi32" }* is the reason for the problem here 14:32.

I think that GLFW can return HWND window and you can also set NO_API in some method and then use DirectX.

I love your videos! I'm wondering how you made spdlog output to a terminal when the application is a window application. On my computer visual studio (I think, or is it the os?) eats all output to cout or cerr, so I have to make spdlog write to a file if I want to read it xD

For anyone watching this in 2021 who happened to create their own fork of GLFW for their project and is running into LNK2019 (linking) errors, specifically involving init.c and vulkan.c, I have found a temporary solution. Granted, this may not be the "right" thing to do, but seeing as (I believe) he changes this overall workflow later anyways, it may be worth doing in order to continue along with the series. So, within your submodule, run: git checkout tags/3.3 then add, commit, and push to your master branch. Hope this helps.

I looked at the repo just to make sure, but you should be able to remove the include for log.h in Hazel.h since it is now in the hzpch.h file

The Window doesn't have to be virtual. If you are determining the actual implementation at compile time you can use pimpl in the header and ifdef the actual implementation.

25:32 idk if i should see it as a chain reaction or a "i know a guy who knows a guy who knows a guy who...."

Hi @TheCherno, I hope this could help, when u use an external lib in your project, like GLFW, I think that is better install it with CMake(the case of GLFW) rather than fork the repo, and create a premake file, because with this u only need to link the libs that u compiled by yourself

I recommend using the latest branch of GLFW, it worked for me, as I think that branch is just more stable overall, and didn't give me any linking errors. And no, the format is fine, the tutorials still work. Stop leaving negative comments and binging about why you want to give up because you are not willing to look hard enough.

glfwSwapInterval(x); if x = 0 >> FPS would've no limit. if x = 1 >> FPS would be set to the monitor's current refreshrate if x = 2 >> FPS would be half the monitor's refreshrate and so on...

I don't know if this will be answered, but i hope... Why do you override virtual inherited functions? Isn't that what virtual does? Never really used override but since you haven't defined the virtual functions shouldn't it be ok? Or does it have to be a pure virtual in order to automatically override?

As the application.cpp creates a window using the Window class 'create' which WindowsWindow inherits from, if you have a LinuxWindow class that also inherited from Window, how would you control which class application.cpp uses?

TheChernoProject: return of the magenta

I have an error saying GLFW.lib is not a win32 application. How can I fix this?

"Here what's up guys, my name's *inaudible*. Welcome back to my game engine series". It's like that in every video man!

4:20 *Sad vulkan noises*

Does anyone know why he passed data from props AND m_Data into glfwCreateWindow()? I don't understand what the point of mixing the two is.

Not sure if this will be seen, but I've followed this series with no errors until now. The error specifically is "An internal error has occurred in the compiler.", produced from the spdlog file logger_impl.h, and I've narrowed the cause down to the 2 logging macros in the WindowsWindow.cpp file. Commenting out these macros avoids the problem and everything works, but it's annoying that I can't use the logging system in this file (and presumably more files in this Platform folder).

Event was unable to read the ToString and EventFn = std::function; had to include the precompile headers. I don't know if it should be done in that header, but at least it compiles now.

When it comes to assertions, what happens if the glfw window isn't initialized in a release build on a user's computer? how would that be handled? this seems like a perfect use-case for exceptions imo, but I'm not sure if I'm missing something

Why is "Init()" and "Shutdown()" inside WindowsWindow class virtual functions?

Not really a fan of the new format, I don't have any problems following or anything, i just liked the other format better

What should be the deciding factor between building third-party libraries from source as demonstrated in this video, versus downloading the pre-compiled binaries and linking them as dependencies?

Tried compiling and linking but getting several errors such as "2>GLFW.lib(window.obj) : error LNK2019: unresolved external symbol __imp_strncpy referenced in function glfwWindowHintString" Anyone hit this and found a solution?

Everytime I run the code, it throws an error at WindowsWindow.h at including glfw3.h, I checked the premake file multiple times and it exactly is the same as the one in Hazel.. I don't understand what's going wrong.

I'm getting Warning C4251 'WinWindow::m_data': struct 'WindowData' needs to have dll-interface to be used by clients of class 'WinWindow' I'm only loosely following the tutorial, and I'm using the same struct WindowProps (called WindowData) in both Window.h and WindowsWindow.h I tried adding the macro responsible for __decl(dllexport/dllimport) to WindowData, but I get similar error messages for each member of WindowData. I don't see why I'm getting the warning and Cherno isn't. I'd really appreciate anyone's feedback. Edit: Cherno is getting the same warnings (but he deselected warnings from the vs error list), it's fine since this project will be shipped with the source code. The warning signifies that there might be problems if you compile the .dll with one compiler and compile the .exe with a different one.

I know that this video is old but I was hoping that someone could explain to me why he made a premake file for glfw but not for spdlog.

Maybe a dumb question, but does anyone know why we forked glfw and have it as a seperate project in Visual Studio? Why didn't we just add it the same way we added spdlog? Why is it so complicated to handle dependencies in C++? :D

great vid! I know this is kind of lost in time, but can anyone explain how we're able to use glfw without first downloading glad or glew or one of the function loading things? Because I thought glfw used OpenGL functions that you had to find in your GPU drivers using one of those, but I can't see any references to them?

Maybe I will understand this later but at this stage, it's unclear to me why spdlog only needed a simple `includedirs` directive while GLFW requires that we include its build configuration in our premake file.

I finally hit the wall. I realize something now as I watch these videos, the GitHut link in the description takes me to the current version of the files. Meaning, that there are things in there I haven't, or the Cherno hasn't done during the upload of the video. I was trying to find an older version that matches the video's version as the Cherno was making changes, but I couldn't. It wasn't until I had downloaded the file from GitHub that I realized I was looking into the future of what the Cherno would do later in the series. I ended up not having a "Platform" folder; I didn't even have a "Windows.h" file in the Hazel folder. Perhaps I did something wrong, at this point, I think I've lost the battle with this "wall" I hit, but hopefully not the war. I believe that if i were watching these videos as they were coming out, that I would be able to keep up, however, that's not the case. I will update on this comment once I've been able to solve this problem... if I am able to. I say this with a bit of hope that I can get past this "wall": I'll see you on the next video's comment section.... maybe :(

Please go back to the old format & write it live! This is so much harder to follow!

I just wanted to post this in case anyone else had this problem and if someone could give me an explanation as to why this is the fix. When compiling the code after implementing the WindowsWindow class, the linker couldn't link to GLFW properly. I changed the static runtime option in the GLFW premake5.lua file to on and then it linked and ran properly. Why is this the case and what did this do?

The final code of the Hazel Engine on github is different from that in each episode. Can someone tell me how to get the source code in these videos? thanks a lot!!

I got an error " attempt to call a nil value (global 'inlcude')", plz how to fix it..

At the end will you be able to make a 3d game in this

Do I have to watch your OpenGL series first before getting into this? or can I just watch this series without doing so?

Nowadays, I prefer CMake for project management, for me is easier to manage, I know that the learning curve is huge, but it worth the work

23:03 wouldn't it be simplier if we just do: void WindowsWindow::SetVSync(bool enabled) { glfwSwapInterval(enabled); m_Data.VSync = enabled; } We are giving a bool to the function anyway and set the SwapInterval to either 0 (false) or 1 (true). There seems to be no need for the "if/else" statement.

Hi thanks for this nice episode, keep it up! Guys can someone explains me how the system knows to create a WindowsWindow and not BlablaWindow ? I don't understand this part.

Man, you can convert all the tabs to the spaces with "Edit->Advanced->Untabify..." :)

with this window can man see the data comes from VR Glasses ?

What is the better way to learn all about opengl, directx and game engines? Are there some books or you can find everything on the Internet?

Editorconfig is your friend and is supported by VS as well as many other IDEs XD

What is actually windows specific at this point about the WindowsWindow?

- Single responsibility principle: Your window class should not directly be responsible for the GLFW initialization - Constructor and destructor exist for a reason so there's no point to write Init() and Shutdown() functions at this stage and from a object point of view, there's never a need for those functions. If you want to reset the state, you just create a new object. - Returning a owning raw pointer from your Create-factory function is rather dangerous, as you now rely on the user of said function to a) know that this is an owning raw pointer and b) properly takeover ownership and destroy it. At zero cost, you can just have the factory function return a unique_ptr and call make_unique, that way the signature indicates that you're a) transferring ownership and b) as long as the user doesn't explicitly misuses the unique_ptr the destruction of the window is guaranteed. - To initialize your member variable, use the initialization list instead of doing it in the constructor.

no idea why he took premake and not cmake, but it complicated the stuff a way more

Maybe call it a GLFWwindow? There are lots of other Windows windows...

17:20

yknow before I got into programming I thought I'd have big tabs vs spaces arguments I wouldn't care about. never happened. I haven't met anyone who cared one way or the other. has anyone been in a tabs vs spaces argument?

no need to include glfw in the header file. struct GLFWWindow; is enough

anyone come across the problem where glClear and glClearColor identifier not found? Any solution

Is "because it's made by MicroSoft for Windows" actually a valid argument? Every game I've played that's offered both DX (11 or 12) and Vulkan on Windows has run better on Vulkan. Clearly the programmers have to write different code to deal with that so there're uncontrolled variables there, but it still doesn't seem right.

I wonder why you use GLFW and not SDL, since SDL does support DirectX.

I get only errors

😍😍

create a binary tree of patreons credit.

Hello, I know that I am a few years behind; however, I am having a linking problem with GLFW. I thought I am doing it the same way as in the video. The issue is LINK2019 unresolved external symbol _glfwSelectPlatform referenced in function glfwInit ..... And a few other similar. Any help would be greatly appreciated.

Will Hazel supports Android or iOS？

On one video, I recall you saying that you would not use glfw and basically create the window yourself from scratch but since it was about "learning opengl" you said you did not care and just wanted it to work or something along those lines and then said that you would create your own if you were writing a game engine. Umm, you are writing a game engine currently?

Please do a github and git tutorial series.

You know you can tell visual studio to automatically insert spaces when you tab, right? Under Tools->Options->Text Editor->All Languages->Tabs. I currently have mine set to make 4 spaces when I tab. You may also have to go to Tools->Options->Text Editor->C/C++->Formatting and uncheck "Automatically indent when I type a tab"

I honestly hate that he just looked through code in these parts. I can't follow anything and when I look at the github in order to follow along, its out of date. I've spent 2 days tryna get this one part working and its not, great.

mwahahaha... The graphics phase shall soon begin

please make videos more frequently one video/lecture in a week is not enough🙏

Anyone know how to solve: Error LNK2019 unresolved external symbol DwmExtendFrameIntoClientArea referenced in function windowProc Hazel GLFW.lib(win32_window.obj 1 I've already tried changing the runtime library settings in project properties as per previous posts, but this error still remains. Thanks in advance.

25 Errors and 43 Warnings...😎

The new video structure is a bit of a headache. My comprehension of your code was better before. This new structure feels rushed and seems like you are already getting bored/irritated with the lessons.

i just CAN NOT follow this :(

I cringe everytime he calls a lua table a "struct".

Why do we still use OpenGL instead of DirectX when 96% games on Steam run on Windows. For me, DirectX is better than OpenGL for the series.

Just like many others in this comment section, I am getting LNK2019 errors. I have tried the solutions in the comments of over an hour worth of browsing and while it helped to get rid of most errors, none of them (premake file changes, cloning old git versions, ...) managed to solve all of them. I guess this tutorial has finally died in 2023 and is no longer functional. Pity, for all the wasted time...

Wow, 4.5 h of blabber until an empty window that we cannot even close - that's an academy record! :q At that rate, we will see our first triangle in a couple of years…

To anyone following this series in 2022 and running into issues with your project not building due to LNK2019 GLFW.lib (init.obj) or (vulkan.obj): A solution that worked for me was checking out the "latest" branch in your GLFW fork. Something with the master branch was giving me errors that I couldn't solve, but this seems to work.

My code builds successfully, but then I run into this error: unable to open file: bin-int/Debug-windows-x86_64/Sandbox/SandboxApp.obj error code 0x80070002

How to fix it "LIBCMTD.lib(exe_main.obj) : error LNK2019" 😣.\bin\Debug-windows-x86_64\Sandbox\Sandbox.exe : fatal error LNK1120