Examples: Fix for Emscripten. GLFW+WGPU: rework examples main loop to handle minimization. (#7844)
Amend 8874787, 71ee2ce
Amend ea39841f (emscripten_mainloop_stub.h)
diff --git a/examples/example_glfw_wgpu/main.cpp b/examples/example_glfw_wgpu/main.cpp
index c5872bd..f510987 100644
--- a/examples/example_glfw_wgpu/main.cpp
+++ b/examples/example_glfw_wgpu/main.cpp
@@ -151,6 +151,11 @@
// - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
// Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
glfwPollEvents();
+ if (glfwGetWindowAttrib(window, GLFW_ICONIFIED) != 0)
+ {
+ ImGui_ImplGlfw_Sleep(10);
+ continue;
+ }
// React to changes in screen size
int width, height;
diff --git a/examples/example_sdl3_sdlrenderer3/main.cpp b/examples/example_sdl3_sdlrenderer3/main.cpp
index 9511415..6efd275 100644
--- a/examples/example_sdl3_sdlrenderer3/main.cpp
+++ b/examples/example_sdl3_sdlrenderer3/main.cpp
@@ -167,6 +167,9 @@
ImGui_ImplSDLRenderer3_RenderDrawData(ImGui::GetDrawData(), renderer);
SDL_RenderPresent(renderer);
}
+#ifdef __EMSCRIPTEN__
+ EMSCRIPTEN_MAINLOOP_END;
+#endif
// Cleanup
ImGui_ImplSDLRenderer3_Shutdown();
diff --git a/examples/libs/emscripten/emscripten_mainloop_stub.h b/examples/libs/emscripten/emscripten_mainloop_stub.h
index 05cf60f..8c4c48e 100644
--- a/examples/libs/emscripten/emscripten_mainloop_stub.h
+++ b/examples/libs/emscripten/emscripten_mainloop_stub.h
@@ -17,20 +17,21 @@
// - 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:
+// Since only about 4 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/
+// - The do { } while (0) is to allow our code calling continue in the main loop.
#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)
+#define EMSCRIPTEN_MAINLOOP_BEGIN MainLoopForEmscriptenP = [&]() { do
+#define EMSCRIPTEN_MAINLOOP_END while (0); }; emscripten_set_main_loop(MainLoopForEmscripten, 0, true)
#else
#define EMSCRIPTEN_MAINLOOP_BEGIN
#define EMSCRIPTEN_MAINLOOP_END
