support emscripten compile

em.ini

@@ -0,0 +1,9 @@
+[binaries]
+c = ['c:/dev/_tools/emsdk/upstream/emscripten/emcc.bat']
+ar =['c:/dev/_tools/emsdk/upstream/emscripten/emar.bat']
+
+[host_machine]
+system = 'emscripten'
+cpu_family = 'wasm'
+cpu = 'wasm'
+endian = 'little'

meson.build

@@ -1,4 +1,10 @@
-project('skunkworks', 'c', default_options: ['buildtype=release'])
+project('skunkworks', 'c',
+	default_options: [
+		'buildtype=release',
+		'strip=true',
+		'debug=false'
+	]
+)
 
 cmake = import('cmake')
 
@@ -20,9 +26,18 @@ opt.add_cmake_defines({
 opt.append_compile_args('c', '-I../subprojects/zlib-1.2.13', '-Isubprojects/zlib-1.2.13/__CMake_build')
 libpng = cmake.subproject('lpng1639', options: opt).dependency('png_static')
 
-libglfw = cmake.subproject('glfw-3.3.8').dependency('glfw')
+opt = cmake.subproject_options()
+opt.add_cmake_defines({'GLFW_BUILD_DOCS': false})
 
-libglew = subproject('glew-2.1.0').get_variable('libglew_dep')
+
+if host_machine.system() == 'emscripten'
+   #libglfw = meson.get_compiler('c').find_library('glfw')
+   deps = [libz, libpng]
+else
+	libglfw = cmake.subproject('glfw-3.3.8', options: opt).dependency('glfw')
+	libglew = subproject('glew-2.1.0').get_variable('libglew_dep')
+	deps = [libz, libpng, libglew, libglfw]
+endif
 
 skunk_sources = [
 	'src/skunkworks.c',
@@ -31,4 +46,8 @@ skunk_sources = [
 	'src/window.c'
 ]
 
-executable('skunktest', skunk_sources, include_directories: 'include', dependencies: [libz, libpng, libglew, libglfw])
+if host_machine.system() == 'emscripten'
+   executable('skunktest', skunk_sources, include_directories: 'include', dependencies: deps, link_args: ['-lglfw', '-lGL', '-s', 'USE_GLFW=3'], name_suffix: 'html')
+else
+	executable('skunktest', skunk_sources, include_directories: 'include', dependencies: deps)
+endif

prebuildem.bat

@@ -0,0 +1,2 @@
+@echo off
+meson setup --cross-file=em.ini --prefer-static buildem

src/gl.h

@@ -3,3 +3,9 @@
 #include <GL/glew.h>
 #pragma clang diagnostic pop
 #include <GLFW/glfw3.h>
+
+#ifdef __EMSCRIPTEN__
+#include <emscripten.h>
+#define GL_GLEXT_PROTOTYPES
+#define EGL_EGLEXT_PROTOTYPES
+#endif

src/test.c

@@ -5,19 +5,30 @@
 
 #include "gl.h"
 
+struct window *win;
+
+void tick();
+
 int main(int argc, char *argv[]) {
-	struct window *win;
 
 	printf("hello world\n");
 	win = sw_window_create(sw_vec2i(640, 480), "Skunkworks");
 	png_sig_cmp(0, 0, 0);
 	glClearColor(0.1f, 0.2f, 0.3f, 1.f);
 
+#ifdef __EMSCRIPTEN__
+	emscripten_set_main_loop(tick, 0, 1);
+#else
 	while (!glfwWindowShouldClose(win->_window)) {
-		glClear(GL_COLOR_BUFFER_BIT);
-		glfwSwapBuffers(win->_window);
-		glfwPollEvents();
+		tick();
 	}
+#endif
 
 	return 0;
 }
+
+void tick() {
+	glClear(GL_COLOR_BUFFER_BIT);
+	glfwSwapBuffers(win->_window);
+	glfwPollEvents();
+}

subprojects/glew-2.1.0/meson.build

@@ -3,6 +3,10 @@ project('glew', 'c')
 gl = dependency('gl')
 inc = include_directories('include')
 c_args = ['-DGLEW_STATIC']
-lib = static_library('glew', 'src/glew.c', include_directories: inc, c_args: c_args, dependencies: gl)
+if host_machine.system() == 'emscripten'
+   lib = static_library('glew', 'src/glew.c', include_directories: inc, c_args: c_args)
+else
+	lib = static_library('glew', 'src/glew.c', include_directories: inc, c_args: c_args, dependencies: gl)
+endif
 
 libglew_dep = declare_dependency(include_directories: inc, link_with: lib, compile_args: c_args)

subprojects/zlib-1.2.13/CMakeLists.txt

@@ -147,10 +147,10 @@ if(MINGW)
     set(ZLIB_DLL_SRCS ${CMAKE_CURRENT_BINARY_DIR}/zlib1rc.obj)
 endif(MINGW)
 
-add_library(zlib SHARED ${ZLIB_SRCS} ${ZLIB_DLL_SRCS} ${ZLIB_PUBLIC_HDRS} ${ZLIB_PRIVATE_HDRS})
+#add_library(zlib SHARED ${ZLIB_SRCS} ${ZLIB_DLL_SRCS} ${ZLIB_PUBLIC_HDRS} ${ZLIB_PRIVATE_HDRS})
 add_library(zlibstatic STATIC ${ZLIB_SRCS} ${ZLIB_PUBLIC_HDRS} ${ZLIB_PRIVATE_HDRS})
-set_target_properties(zlib PROPERTIES DEFINE_SYMBOL ZLIB_DLL)
-set_target_properties(zlib PROPERTIES SOVERSION 1)
+#set_target_properties(zlib PROPERTIES DEFINE_SYMBOL ZLIB_DLL)
+#set_target_properties(zlib PROPERTIES SOVERSION 1)
 
 if(NOT CYGWIN)
     # This property causes shared libraries on Linux to have the full version
@@ -160,7 +160,7 @@ if(NOT CYGWIN)
     #
     # This has no effect with MSVC, on that platform the version info for
     # the DLL comes from the resource file win32/zlib1.rc
-    set_target_properties(zlib PROPERTIES VERSION ${ZLIB_FULL_VERSION})
+    #set_target_properties(zlib PROPERTIES VERSION ${ZLIB_FULL_VERSION})
 endif()
 
 if(UNIX)
@@ -175,7 +175,7 @@ elseif(BUILD_SHARED_LIBS AND WIN32)
 endif()
 
 if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL )
-    install(TARGETS zlib zlibstatic
+    install(TARGETS zlibstatic
         RUNTIME DESTINATION "${INSTALL_BIN_DIR}"
         ARCHIVE DESTINATION "${INSTALL_LIB_DIR}"
         LIBRARY DESTINATION "${INSTALL_LIB_DIR}" )