Apparently I was able to get past the memory issue by compiling with optimization flag -O3.
I will check out that link though, it might help me in the future. Thanks! On Tuesday, November 2, 2021 at 6:05:15 AM UTC-5 Floh wrote: > > However, I get a different (unrelated) error now which is that the > browser crashes because it runs out of memory... > > This sounds like a memory leak, AFAIK memory growth is now enabled by > default in WASM, so ALLOW_MEMORY_GROWTH is redundant. > > Emscripten has various features to aid with memory debugging, this is > probably a good starting point: > > https://web.dev/webassembly-memory-debugging/ > On Tuesday, 2 November 2021 at 12:00:26 UTC+1 Floh wrote: > >> Ah dang, yeah totally makes sense. I guess that's one of those pitfalls >> in C that are so obvious that one gets blind about. >> >> > Of course I have no idea WHY any of this needs to be done. >> >> The line: >> >> EmscriptenWebGLContextAttributes attrs; >> >> ...means that 'attrs' has random memory content (because it's a C struct, >> not a C++ class with constructor), and the >> emscripten_webgl_init_context_attributes() call initializes the memory to >> something sane (probably just clearing the memory to zero). This >> initialization pattern is fairly common in C APIs, but not in C++ APIs. >> >> Cheers! >> >> On Tuesday, 2 November 2021 at 08:09:08 UTC+1 [email protected] >> wrote: >> >>> It looks like I have found a solution thanks to someone in the Discord >>> server. Here is what I changed: >>> >>> EmscriptenWebGLContextAttributes attrs; >>> attrs.antialias = true; >>> attrs.majorVersion = 3; >>> attrs.minorVersion = 2; >>> attrs.alpha = true; >>> attrs.powerPreference = EM_WEBGL_POWER_PREFERENCE_DEFAULT; >>> >>> // The following lines must be done in exact order, or it will break! >>> emscripten_webgl_init_context_attributes(&attrs); // you MUST init >>> the attributes before creating the context >>> attrs.majorVersion = 3; // you MUST set the version AFTER the above >>> line >>> EMSCRIPTEN_WEBGL_CONTEXT_HANDLE webgl_context = >>> emscripten_webgl_create_context("#canvas", &attrs); >>> emscripten_webgl_make_context_current(webgl_context); >>> mainContext = SDL_GL_CreateContext(window); >>> >>> When you modify my main.cpp with this code then it actually shows the >>> game on the screen and all of the above errors I mentioned disappear. So >>> the solution is to call emscripten_webgl_init_context_attributes between >>> creating the attributes and before creating the context. However, if you do >>> that then it sets up the webgl context using OpenGL ES 2.0 (WebGL 1.0) >>> which is not what I want (because I would need to change all my shader >>> code). So that's why you need to set the attributes AGAIN after calling it >>> (to set majorVersion=3) which results in OpenGL ES 3.0 / WebGL 2.0. >>> >>> Of course I have no idea WHY any of this needs to be done. I hope this >>> can either be fixed or documented somewhere with an explanation. >>> >>> I managed to copy and paste this code into my larger game project and it >>> worked like a charm. However, I get a different (unrelated) error now which >>> is that the browser crashes because it runs out of memory... but at least I >>> can see the game now. The preloaded data file is ~80 MB which isn't huge by >>> video game standards, but it might be too big for the browser to download. >>> I did set ALLOW_MEMORY_GROWTH=1 but that didn't seem to prevent the issue. >>> If anyone can help me out with that too please let me know. Thanks. >>> >>> On Monday, November 1, 2021 at 9:20:16 AM UTC-5 Floh wrote: >>> >>>> PS: if you just want to get something on screen in a cross-platform >>>> application, but don't care if it's SDL2 or GL, check out my sokol headers: >>>> >>>> https://floooh.github.io/sokol-html5/ >>>> >>>> No guarantee that this will protect you from any C++ shenanigans >>>> though, the headers can be used from C++, but since I prefer plain old C >>>> these days, most of the sample code is written in C (and the few C++ >>>> samples - mainly the Dear ImGui stuff - doesn't use the STL). >>>> On Monday, 1 November 2021 at 15:16:29 UTC+1 Floh wrote: >>>> >>>>> I'm also able to reproduce the problem on macOS with Chrome and >>>>> Safari, but no idea either what's going wrong there. >>>>> >>>>> However, I suspect it's not the use of std::string, but that iostream >>>>> is the culprit, because if I replace std::cout with printf but keep >>>>> std::string, it works (replacing cout with printf is a good idea anyway, >>>>> because cout adds an incredible amount of bloat last I checked). >>>>> >>>>> On Monday, 1 November 2021 at 12:38:16 UTC+1 [email protected] >>>>> wrote: >>>>> >>>>>> I'm glad someone was able to reproduce it, but that didn't answer any >>>>>> of my questions. >>>>>> >>>>>> I've tried a few more things and maybe the issue is related to >>>>>> strings in some way. If I add a class that takes a string as a parameter >>>>>> in >>>>>> the constructor, and then ONLY if I instantiate it, like so: >>>>>> >>>>>> class Test >>>>>> { >>>>>> public: >>>>>> Test(std::string test) {} ; >>>>>> }; >>>>>> >>>>>> int main() >>>>>> { >>>>>> Test test("test"); >>>>>> InitOpenGL(1280, 720, window, mainContext); >>>>>> BeforeMainLoop(); >>>>>> >>>>>> return 1; >>>>>> } >>>>>> >>>>>> Then that also results in a black screen. Instantiating a vector of >>>>>> strings also results in a black screen, like so: >>>>>> std::vector<std::string> languages = { "english", "japanese" }; >>>>>> >>>>>> And my original problem with the Log function also happens to involve >>>>>> strings on some level. If I change the constructor from a string to a >>>>>> const >>>>>> char* then it works. But changing all instances of strings to const >>>>>> char* >>>>>> is not ideal (my program needs strings), and I actually tried that with >>>>>> the >>>>>> Log function and that did not help, so I'm still looking for a solution. >>>>>> So >>>>>> hopefully this information is helpful for someone to figure out what is >>>>>> wrong and how to fix it. >>>>>> >>>>>> >>>>>> On Sunday, October 31, 2021 at 12:23:53 AM UTC-5 Shlomi Fish wrote: >>>>>> >>>>>>> Hi all! >>>>>>> >>>>>>> On Sat, 30 Oct 2021 18:46:19 -0700 (PDT) >>>>>>> Anton Strickland <[email protected]> wrote: >>>>>>> >>>>>>> > I have been stuck on a very simple issue for multiple days and >>>>>>> need someone >>>>>>> > who knows what they are doing. I'm trying to use SDL2 and WebGL2 >>>>>>> (OpenGL ES >>>>>>> > 3) and sometimes it works, but sometimes it doesn't, depending on >>>>>>> seemingly >>>>>>> > arbitrary code. Please help. See here for the full details and >>>>>>> source code: >>>>>>> > >>>>>>> > >>>>>>> https://gist.github.com/AntonStrickland/433c911151ca73826ee679b120fe8d9e >>>>>>> >>>>>>> > >>>>>>> >>>>>>> Note that I was able to reproduce the issue on fedora v34 x86-64 >>>>>>> with firefox: >>>>>>> >>>>>>> ``` >>>>>>> System: >>>>>>> Host: telaviv1.shlomifish.org Kernel: 5.14.14-200.fc34.x86_64 >>>>>>> x86_64 >>>>>>> bits: 64 Desktop: Xfce 4.16.0 Distro: Fedora release 34 (Thirty >>>>>>> Four) >>>>>>> CPU: >>>>>>> Info: Dual Core model: Intel Core i3-2100 bits: 64 type: MT MCP >>>>>>> cache: >>>>>>> L2: 3 MiB >>>>>>> Speed: 2750 MHz min/max: 1600/3100 MHz Core speeds (MHz): 1: 2750 >>>>>>> 2: 2698 3: 2709 4: 2694 >>>>>>> Graphics: >>>>>>> Device-1: Intel 2nd Generation Core Processor Family Integrated >>>>>>> Graphics >>>>>>> driver: i915 v: kernel Display: x11 server: X.Org 1.20.11 driver: >>>>>>> loaded: >>>>>>> modesetting unloaded: fbdev,vesa resolution: 1920x1080~60Hz >>>>>>> OpenGL: renderer: Mesa DRI Intel HD Graphics 2000 (SNB GT1) >>>>>>> v: 3.3 Mesa 21.1.8 >>>>>>> ``` >>>>>>> >>>>>>> As a side note: main.cpp has some trailing whitespace: >>>>>>> https://perl-begin.org/tutorials/bad-elements/#trailing-whitespace >>>>>>> >>>>>>> > Basically, I have a simple program (just over 100 lines of code) >>>>>>> that >>>>>>> > changes the background color of the screen by calling glClear(). >>>>>>> Probably >>>>>>> > the most basic OpenGL program one can write. When the color is >>>>>>> pink, that >>>>>>> > means it's working, and when it's black, it's not working. In the >>>>>>> above >>>>>>> > link there is main.cpp which works correctly. I have been doing >>>>>>> trial and >>>>>>> > error for this past week commenting out random lines of code to >>>>>>> isolate the >>>>>>> > problem, but it seems like changing arbitrary lines of code stops >>>>>>> it from >>>>>>> > working. I've noticed that it happens when calling some SDL >>>>>>> functions, but >>>>>>> > even just commenting out printing to the console is enough to >>>>>>> break it. See >>>>>>> > main.cpp for details. >>>>>>> > >>>>>>> > I don't know if this is just an issue with me not understanding >>>>>>> how this >>>>>>> > works or if this is an actual bug in emscripten or the SDL port. >>>>>>> it's >>>>>>> > frustrating because when it works, it works all the way (I can use >>>>>>> shaders >>>>>>> > and textures to have a working app), but if I change just a tiny >>>>>>> little >>>>>>> > thing (even just commenting out an unrelated line of code), >>>>>>> suddenly >>>>>>> > nothing works at all. I have no idea where to even start debugging >>>>>>> this. >>>>>>> > >>>>>>> > I would imagine that there has to be a way to do this since people >>>>>>> are >>>>>>> > obviously making WebGL games in C++, but since there are no >>>>>>> tutorials >>>>>>> > online for how to do that it becomes impossible to even set up a >>>>>>> simple >>>>>>> > "hello world" script. I purchased a book on how to make games in >>>>>>> web >>>>>>> > assembly but they use the SDL renderer and not OpenGL rendering. >>>>>>> Other >>>>>>> > OpenGL web assembly tutorials just use OpenGL without SDL. Surely >>>>>>> there >>>>>>> > must be a way to use them together as I have done for my desktop >>>>>>> app? >>>>>>> > >>>>>>> > I have already reached out on the discord but to no avail so far. >>>>>>> Someone >>>>>>> > suggested adding -fsanitize=address when compiling but that >>>>>>> actually causes >>>>>>> > the above working code to stop working. I don't really have the >>>>>>> time to >>>>>>> > just wait for an answer so I'm hoping this post will get the >>>>>>> attention of >>>>>>> > more people. >>>>>>> > >>>>>>> > So I know this is getting long, but I'm very confused. Since >>>>>>> technically by >>>>>>> > code works, but it's one step away from breaking, and I have no >>>>>>> idea what >>>>>>> > that step is or why. My ultimate goal is to copy and paste this >>>>>>> code into a >>>>>>> > larger project, but every time I do so, it results in a black >>>>>>> screen with >>>>>>> > no indication of what I did wrong. >>>>>>> > >>>>>>> > I would like to understand a few things: >>>>>>> > >>>>>>> > - Is this a problem with my code, my makefile, SDL, or emscripten? >>>>>>> > - If this is not a problem with my code, is someone going to fix >>>>>>> the >>>>>>> > issue? >>>>>>> > - If my desktop code is Open GL 3.3, should I be using OpenGL ES 3 >>>>>>> or is >>>>>>> > that part of the problem? And what files do I need to include and >>>>>>> where do >>>>>>> > I get them (if what I have isn't correct?) >>>>>>> > - What is the proper way to set up an emscripten webgl context? My >>>>>>> > source code includes two different ways of setting it up and I am >>>>>>> not sure >>>>>>> > which is correct, even after trial and error. >>>>>>> > - Can I get someone who is willing to at least compile the code >>>>>>> > themselves and try out different solutions until they find >>>>>>> something that >>>>>>> > can provide an explanation? I don't want someone to suggest adding >>>>>>> a >>>>>>> > single argument to my makefile, and then hours later I get home to >>>>>>> try it out >>>>>>> > and realize that it actually causes the program to fail. My >>>>>>> program is small >>>>>>> > enough that someone can copy and paste it together, compile it, >>>>>>> and run it >>>>>>> > in less than 2 minutes. There is no reason to not do that yourself >>>>>>> to >>>>>>> > check that it works before suggesting a solution to me. I am just >>>>>>> a little >>>>>>> > frustrated at this point so please don't take it the wrong way, I >>>>>>> just >>>>>>> > want someone to take me seriously so I can move on to the next >>>>>>> step of my >>>>>>> > project. >>>>>>> > - If this mailing list is not the best place to quickly get help >>>>>>> like >>>>>>> > that, who do I need to contact? I am willing to pay for work if >>>>>>> that needs >>>>>>> > to be done, but I don't think that should be necessary to get a >>>>>>> "hello >>>>>>> > world" program up and running, especially when I've already come >>>>>>> this far >>>>>>> > on my own. >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> >>>>>>> Shlomi Fish https://www.shlomifish.org/ >>>>>>> Free (Creative Commons) Music Downloads, Reviews and more - >>>>>>> https://jamendo.com/ >>>>>>> >>>>>>> <LeoNerd> “I hear eclipse is really nice, but I’m still waiting for >>>>>>> it to >>>>>>> load.” >>>>>>> — Freenode’s #perl >>>>>>> >>>>>>> Please reply to list if it's a mailing list post - >>>>>>> https://shlom.in/reply . >>>>>>> >>>>>> -- You received this message because you are subscribed to the Google Groups "emscripten-discuss" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. 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