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// What does this file solves?
// - Since Dear ImGui 1.00 we took pride that most of our examples applications had their entire
// main-loop inside the main() function. That's because:
// - It makes the examples easier to read, keeping the code sequential.
// - It permit the use of local variables, making it easier to try things and perform quick
// changes when someone needs to quickly test something (vs having to structure the example
// in order to pass data around). This is very important because people use those examples
// to craft easy-to-past repro when they want to discuss features or report issues.
// - It conveys at a glance that this is a no-BS framework, it won't take your main loop away from you.
// - It is generally nice and elegant.
// - However, comes Emscripten... it is a wonderful and magical tech but it requires a "main loop" function.
// - Only some of our examples would run on Emscripten. Typically the ones rendering with GL or WGPU ones.
// - I tried to refactor those examples but felt it was problematic that other examples didn't follow the
// same layout. Why would the SDL+GL example be structured one way and the SGL+DX11 be structured differently?
// Especially as we are trying hard to convey that using a Dear ImGui backend in an *existing application*
// should requires only a few dozens lines of code, and this should be consistent and symmetrical for all backends.
// - So the next logical step was to refactor all examples to follow that layout of using a "main loop" function.
// This worked, but it made us lose all the nice things we had...
// Since only about 3 examples really need to run with Emscripten, here's our solution:
// - Use some weird macros and capturing lambda to turn a loop in main() into a function.
// - Hide all that crap in this file so it doesn't make our examples unusually ugly.
// As a stance and principle of Dear ImGui development we don't use C++ headers and we don't
// want to suggest to the newcomer that we would ever use C++ headers as this would affect
// the initial judgment of many of our target audience.
// - Technique is based on this idea: https://github.com/ocornut/imgui/pull/2492/
#ifdef __EMSCRIPTEN__
#include <emscripten.h>
#include <functional>
static std::function<void()> MainLoopForEmscriptenP;
static void MainLoopForEmscripten() { MainLoopForEmscriptenP(); }
#define EMSCRIPTEN_MAINLOOP_BEGIN MainLoopForEmscriptenP = [&]()
#define EMSCRIPTEN_MAINLOOP_END ; emscripten_set_main_loop(MainLoopForEmscripten, 0, true)
#else
#define EMSCRIPTEN_MAINLOOP_BEGIN
#define EMSCRIPTEN_MAINLOOP_END
#endif
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