Make it easier to enable support for compiling emscripten to wasm.

Add some documentation.


git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/branches/ogl-es@5638 dfc29bdd-3216-0410-991c-e03cc46cb475

examples/01.HelloWorld_emscripten/Makefile

@@ -48,7 +48,11 @@ all_win32 clean_win32 static_win32: SYSTEM=Win32-gcc
 all_win32 clean_win32 static_win32: SUF=.exe
 all_emscripten clean_emscripten: SUF=.html
 all_emscripten: CXXFLAGS += -fno-exceptions -fno-rtti -fstrict-aliasing  -std=gnu++11 -U__STRICT_ANSI__
+# Pass on a custom html file.
+#all_emscripten: CXXFLAGS += --shell-file shell_minimal.html
 all_emscripten: LDFLAGS += -lGL -lSDL --preload-file ../../media@/media -s ALLOW_MEMORY_GROWTH=1 -s NO_EXIT_RUNTIME=1
+#If you know the maximum memory (in bytes) which your application need then set it. It can speed things up a lot.
+#all_emscripten: LDFLAGS += -s TOTAL_MEMORY=268435456
 # You need the FULL_ES2 when using EDT_OGLES2 driver
 #all_emscripten: LDFLAGS += -s FULL_ES2=1 
 static_win32: CPPFLAGS += -D_IRR_STATIC_LIB_
@@ -57,6 +61,13 @@ static_win32: LDFLAGS += -lgdi32 -lwinspool -lcomdlg32 -lole32 -loleaut32 -luuid
 # name of the binary - only valid for targets which set SYSTEM
 DESTPATH = $(BinPath)/$(Target)$(SUF)
 
+# Enable compiling to WASM and not just asm.js (you have to set it in the engine Makefile as well)
+ifdef EMSCRIPTEN
+  ifdef WASM
+    CXXFLAGS += -s WASM=1
+  endif
+endif
+
 emscripten: all_emscripten
 
 all_linux all_win32 all_emscripten static_win32:

examples/01.HelloWorld_emscripten/readme.txt

@@ -20,3 +20,5 @@ emmake make emscripten
 
 Go into examples/01.HelloWord_emscripten folder and call:
 emmake make all_emscripten
+
+Note: The shell_minimal.html is currently not used (as resizing isn't working yet correctly), but can be enabled in the Makefile.

source/Irrlicht/Makefile

@@ -90,6 +90,9 @@ ifdef EMSCRIPTEN
   else
     CFLAGS := -O3 -DPNG_THREAD_UNSAFE_OK -DPNG_NO_MMX_CODE -DPNG_NO_MNG_FEATURES
   endif
+  ifdef WASM
+    CXXFLAGS += -s WASM=1
+  endif  
 else
   CFLAGS := -O3 -fexpensive-optimizations -DPNG_THREAD_UNSAFE_OK -DPNG_NO_MMX_CODE -DPNG_NO_MNG_FEATURES
 endif