Examples: Emscripten: Tweaks for size. (#2494)

examples/.gitignore

@@ -25,6 +25,7 @@ project.xcworkspace
 xcuserdata
 
 ## Emscripten output
+*.o.tmp
 *.out.js
 *.out.wasm
 example_emscripten/example_emscripten.*

examples/example_emscripten/Makefile

@@ -24,10 +24,12 @@ UNAME_S := $(shell uname -s)
 EMS = -s USE_SDL=2 -s WASM=1
 EMS += -s ALLOW_MEMORY_GROWTH=1 -s BINARYEN_TRAP_MODE=clamp
 EMS += -s DISABLE_EXCEPTION_CATCHING=1 -s NO_EXIT_RUNTIME=0
-EMS += -s ASSERTIONS=1 -s SAFE_HEAP=1
+EMS += -s ASSERTIONS=1 -s NO_FILESYSTEM=1
+#EMS += -s SAFE_HEAP=1    ## Adds overhead
 
 CPPFLAGS = -I../ -I../../
-CPPFLAGS += -g -Wall -Wformat -O3
+#CPPFLAGS += -g
+CPPFLAGS += -Wall -Wformat -Os
 CPPFLAGS += $(EMS)
 LIBS = $(EMS)
 LDFLAGS = --shell-file shell_minimal.html

examples/example_emscripten/main.cpp

@@ -14,7 +14,7 @@
 #include <SDL.h>
 #include <SDL_opengles2.h>
 
-// Emscripten requires to have full control over the main loop. We're going to store our SDL book-keeping variables globally. 
+// Emscripten requires to have full control over the main loop. We're going to store our SDL book-keeping variables globally.
 // Having a single function that acts as a loop prevents us to store state in the stack of said function. So we need some location for this.
 SDL_Window*     g_Window = NULL;
 SDL_GLContext   g_GLContext = NULL;
@@ -63,6 +63,10 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
 
+    // For an Emscripten build we are disabling file-system access, so let's not attempt to do a fopen() of the imgui.ini file.
+    // You may manually call LoadIniSettingsFromMemory() to load settings from your own storage.
+    io.IniFilename = NULL;
+
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
@@ -90,7 +94,7 @@ int main(int, char**)
     emscripten_set_main_loop_arg(main_loop, NULL, 0, true);
 }
 
-void main_loop(void* arg) 
+void main_loop(void* arg)
 {
     ImGuiIO& io = ImGui::GetIO();
     IM_UNUSED(arg); // We can pass this argument as the second parameter of emscripten_set_main_loop_arg(), but we don't use that.