nanovg VS imgui

I use nanovg for my projects and it works surprisingly well for its size. It integration is pretty simple .... if you know a little bit of OpenGL, otherwise there is a slight learning curve.

The "engine" is built on top of amazing https://www.lwjgl.org/ and https://github.com/bkaradzic/bgfx/, and UI system is baked by https://github.com/memononen/nanovg and https://github.com/facebook/yoga

It's a library for drawing vector shapes, sort of like SVG - https://github.com/memononen/nanovg The old way in the SDK was with GDI+, but the benefit of a vector format is scalability to higher resolutions and better GPU usage. The workaround potentially costs some frames, but its better than bust panels for now.

If you are a beginner in computer graphics, I strongly suggest you to look at the nanovg library: it contains all the primitives you might want to render (circles, lines, filled polygons, text, images, ...). Integrating it in existing codebase is not that hard, since the library is rather small.

NanoVG is the closest thing I came across when I had a similar quesiton: https://github.com/memononen/NanoVG

unfortunately it doesn't seem like it's getting steady updates now unlike the last time I checked. But I imagine it's pretty mature at this point. There also seem to be ports in Metal/DX11 if you didn't want to be stuck in OpenGL.

Also there's NanoVG if you really want a vector api in C, but don't need anti-aliased clipping.

Getting sufficient antialiasing quality for 2D graphics is difficult on GPUs. https://github.com/memononen/nanovg accomplishes this with GL2/GLES2 level hardware for most of the stuff one would want to render as part of a GUI. My project https://github.com/styluslabs/nanovgXC supports rendering arbitrary paths with exact coverage antialiasing, but requires GLES3.1 or GL4 level hardware for reasonable performance.

> to learn the 'nuts and bolts' of rendering

These nuts and bolts are very different between CPU and GPU. CPU-based libraries are painting pixels in bitmaps in system memory. Most GPU-based libraries are uploading indexed triangle meshes, and rendering them with weird shaders.

Worse, there're no good open source implementations of GPU-based ones. Microsoft ships an implementation as a part of OS (Direct2D) but it's not open source. Linux simply doesn't have an equivalent.

At least for initial versions, consider C interop with this https://github.com/memononen/nanovg It cuts a few corners (no cleartype for text, CPU overhead for repeated rendering of same static paths) but it's still good overall, simple, and easy to use.

> My only concern with C# is the cross compatibility

Works well on Linux, Windows and OSX, including ARM CPUs. Not sure about Android and iOS, never tested.

My largest concern with C# would be performance. Technically the language allows to code in any style, but most guides and examples are using OO-heavy one.

include(cmake/CPM.cmake) function(raylib_imgui_setup_dependencies) message(STATUS "Include Dear ImGui") FetchContent_Declare( ImGui GIT_REPOSITORY https://github.com/ocornut/imgui GIT_TAG 277ae93c41314ba5f4c7444f37c4319cdf07e8cf) # v1.90.4 FetchContent_MakeAvailable(ImGui) FetchContent_GetProperties(ImGui SOURCE_DIR IMGUI_DIR) add_library( imgui STATIC ${imgui_SOURCE_DIR}/imgui.cpp ${imgui_SOURCE_DIR}/imgui_draw.cpp ${imgui_SOURCE_DIR}/imgui_widgets.cpp ${imgui_SOURCE_DIR}/imgui_tables.cpp) target_include_directories(imgui INTERFACE ${imgui_SOURCE_DIR}) include(cmake/CPM.cmake) message(STATUS "Include dbg-macro") cpmaddpackage( "gh:sharkdp/dbg-macro#fb9976f410f8b29105818b20278cd0be0e853fe8" )# v0.5.1 message(STATUS "Include fmtlib") cpmaddpackage("gh:fmtlib/fmt#e69e5f977d458f2650bb346dadf2ad30c5320281" )# 10.x message(STATUS "Include raylib") cpmaddpackage("gh:raysan5/raylib#ae50bfa2cc569c0f8d5bc4315d39db64005b1b0" )# v5.0 message(STATUS "Include spdlog") cpmaddpackage("gh:gabime/spdlog#7c02e204c92545f869e2f04edaab1f19fe8b19fd" )# v1.13.0 message(STATUS "Include rlImGui") FetchContent_Declare( rlImGui GIT_REPOSITORY https://github.com/raylib-extras/rlImGui GIT_TAG d765c1ef3d37cf939f88aaa272a59a2713d654c9) FetchContent_MakeAvailable(rlImGui) FetchContent_GetProperties(rlImGui SOURCE_DIR RLIMGUI_DIR) add_library(rlimgui STATIC ${rlimgui_SOURCE_DIR}/rlImgui.cpp) target_link_libraries(rlimgui PRIVATE imgui raylib) target_include_directories(rlimgui INTERFACE ${rlimgui_SOURCE_DIR}) endfunction()

Immediate mode is a fuzzy concept, as witnessed by this writeup: https://github.com/ocornut/imgui/wiki/About-the-IMGUI-paradi...

It's fun to see the evolution in e.g. these examples of image loading for Dear Imgui:

https://github.com/ocornut/imgui/wiki/Image-Loading-and-Disp...

DirectX9 will even load the image for you, DirectX11 okay we get a few more structures to fill out, DirectX12 is where it goes off the rails and we are filling out a bunch of UNKNOWN DONT_CARE JUST_DO_IT. Then of course Vulkan is the one that gets the big fat "this probably won't actually work for you" warning.

I understand whats happening, but you know sometimes I just want to display a fucking image.

ImGui is engine/GPU agnostic

Themeing isn't a just a retained mode thing, you can do wonders with immediate UIs, even thought (dear)ImGui doesn't provide much, you can still do wonders: https://github.com/ocornut/imgui/issues/707#issuecomment-362...

More on that topic: https://www.youtube.com/watch?v=Z1qyvQsjK5Y

Bonus: If you want to make desktop app with UI, then this is another great C++ library and it's also simple to learn as well. https://github.com/ocornut/imgui.

AFAIK the Rust equivalent to C++'s Dear ImGui is egui.

They use a Dear ImGui, a C++ GUI library.

Aside from bugs and driver issues, Wayland has some unfortunate design limitations. For example, Dear ImGui multi-viewports don't work because "Wayland doesn't let application read or write windows positions."

https://github.com/ocornut/imgui/wiki/Multi-Viewports

This is a feature available on Windows, macOS, and of course X11. Making choices like this means desktop Linux becomes even more of a weird island that nobody wants to support.