From f07b075052878d6e5247082dcbe019e7a3b0d642 Mon Sep 17 00:00:00 2001
From: Sebastian Krzyszkowiak <dos@dosowisko.net>
Date: Tue, 8 Jan 2019 04:57:30 +0100
Subject: [PATCH] emscripten: install a callback for visibility changes

Fixes an issue where focus blur event was being dispatched only after
the game has been focused again.
---
 src/libsuperderpy.c | 7 +++++++
 src/libsuperderpy.h | 1 +
 2 files changed, 8 insertions(+)

diff --git a/src/libsuperderpy.c b/src/libsuperderpy.c
index 6a1d744..aff4cc0 100644
--- a/src/libsuperderpy.c
+++ b/src/libsuperderpy.c
@@ -384,6 +384,12 @@ SYMBOL_INTERNAL void libsuperderpy_emscripten_mainloop(void* game) {
 		emscripten_cancel_main_loop();
 	}
 }
+
+SYMBOL_INTERNAL EM_BOOL libsuperderpy_emscripten_visibility_change(int eventType, const EmscriptenVisibilityChangeEvent* visibilityChangeEvent, void* game) {
+	libsuperderpy_emscripten_mainloop(game);
+	return false;
+}
+
 #endif
 
 SYMBOL_EXPORT int libsuperderpy_run(struct Game* game) {
@@ -392,6 +398,7 @@ SYMBOL_EXPORT int libsuperderpy_run(struct Game* game) {
 		return ret;
 	}
 #ifdef __EMSCRIPTEN__
+	emscripten_set_visibilitychange_callback(game, false, libsuperderpy_emscripten_visibility_change);
 	emscripten_set_main_loop_arg(libsuperderpy_emscripten_mainloop, game, 0, true);
 	return 0;
 #else
diff --git a/src/libsuperderpy.h b/src/libsuperderpy.h
index 9ccecdd..b9d90fa 100644
--- a/src/libsuperderpy.h
+++ b/src/libsuperderpy.h
@@ -63,6 +63,7 @@ struct GamestateResources;
 #include <allegro5/allegro_iphone.h>
 #elif defined(__EMSCRIPTEN__)
 #include <emscripten/emscripten.h>
+#include <emscripten/html5.h>
 #endif
 
 #include "character.h"