added vulkan build, and cmake files, removed premake4.lua

Why I made this - I made it as a "test task for Vulkan related job" a year ago, for me this project has no real use. I would recommend for everyone use imgui if you look for production-ready Vulkan UI, also look on egui. I will not support or update this project at all, the last update was just to fix bugs and Validation errors.

Description - nanovg in C, no external dependencies. GLFW used only by one example (look examples description, there is example without using GLFW).

Contact: Join discord server

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To launch - copy builded binary to example folder(or launch when this folder is current as on build example commands below). Because required fonts and images/shaders to load.

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Known bugs-related info:

• Bug - DPI scale is broken when it !=1, Currectly - DPI scale set to 1 always. Read danilw/nanovg-vulkan-glfw-integration-demo#1
• Bug - crash on resize on AMD-GPU only in Linux in Wayland. Read danilw/nanovg-vulkan-glfw-integration-demo#2
• Fix what Cppcheck pointing, unused variables etc, not bugs.
• Performance - after SubiyaCryolite pull #7 performance of Vulkan version very close to OpenGL.

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Build:

(use cmake to build on Windows, Windows/Linux supported and tested)

git clone --recursive https://github.com/danilw/nanovg_vulkan
cd nanovg_vulkan/example
mkdir build
cd build
cmake ../
make
cd ../
./build/example-vk
./build/example-vk_min_no_glfw

Look Examples description below there link to repository with C only minimal example without dependencies not using any library.

MoltenVK note - after TOPOLOGY_TRIANGLE_LIST update(look below) this Vulkan port does work on MoltenVK(Mac/etc) but I dont have it to test so you should make cmake config to build it and launch by yourself.

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Examples description:

Multiple frames in flight - example_vulkan.c is multiple frames in flight example, example_vulkan_min_no_glfw.c is single frame in flight. Clearly visible on FPS - with multiple frames about 3x better FPS.

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example_vulkan.c - minimal NanoVG example that use GLFW.

example_vulkan_min_no_glfw.c - same as above but not using GLFW, supported Linux and Windows.

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2023 update - huge performance improvement thanks to @SubiyaCryolite

SubiyaCryolite pull request Optimizations > Cached Descriptor Sets, Implied Multiple Frames in Flight, Fencing for faster perf

• Support for multiple command buffers, specifically one per swap-chain image / buffer
• Caching of descriptor sets, removing the need to create new ones per draw func or to call vkResetDescriptorPool per frame.
• Under example_vulkan, using vkWaitForFences to control rendering as opposed to vkQueueWaitIdle (seems to be the biggest perf booster). This change also has implied "multiple frames in flight" as dictated by the swap-chain image count.
• Using persisted mapped buffers via VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT instead of VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT , allows to skip calls to vkMap/UnmapMemory per frame

Link to version before this change 5ba9d31, this change 10d5211.

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2022 update - thanks to @nidefawl pull request with lots of changes:

In this PR:

1. Merge latest nanovg

2. Fix Stencil Strokes: I added a new enum to handle the 3 different pipelines used for stencil strokes.
   I wanted to also use enums for the fill-path (nvgFill) to make the code cleaner, but haven't done that yet.

3. I combined the 2 CMakeLists.txt into example/CMakeLists.txt and added some bits to make it easier to build and debug in MSVC/VSCode.

4. I added GLAD as default gl-loader for the GL3 example. It can be switched back to GLEW (I kept glew to allow easier merge with main nanovg)

5. I Increased the number of swapchain images to minimum 3 and updated the swapchain barrier to gain some extra performance.

6. Spacebar renders the demo multiple times to add some 'load' when comparing performance

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2021 update - fixed all errors, this code has no Validation errors and work correctly everywhere.

Thanks to @fzwoch commits by default used TOPOLOGY_TRIANGLE_LIST, because TOPOLOGY_TRIANGLE_FAN is optional in Vulkan.

To enable TOPOLOGY_TRIANGLE_FAN edit src/nanovg_vk.h and set there #define USE_TOPOLOGY_TRIANGLE_FAN

Depth order bug on AMD fix by @leranger 6ee1009.

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Screenshot of Vulkan version from Linux:

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Read original readme for more info about NanoVG API https://github.com/memononen/nanovg