ANDROID: Add GLAD support

backends/graphics/android/android-graphics.cpp

@@ -223,8 +223,7 @@ void AndroidGraphicsManager::touchControlNotifyChanged() {
 void *AndroidGraphicsManager::getProcAddress(const char *name) const {
 	ENTER("%s", name);
 
-	// TODO: Support dynamically loaded OpenGL
-	return nullptr;
+	return androidGLgetProcAddress(name);
 }
 
 bool AndroidGraphicsManager::notifyMousePosition(Common::Point &mouse) {

backends/graphics3d/android/android-graphics3d.h

@@ -134,8 +134,6 @@ protected:
 
 	void refreshScreen();
 
-	void *getProcAddress(const char *name) const;
-
 private:
 	void initOverlay();
 

backends/platform/android/android.cpp

@@ -40,6 +40,7 @@
 // for the Android port
 #define FORBIDDEN_SYMBOL_EXCEPTION_printf
 
+#include <EGL/egl.h>
 #include <sys/time.h>
 #include <sys/resource.h>
 #include <sys/system_properties.h>
@@ -120,6 +121,11 @@ void checkGlError(const char *expr, const char *file, int line) {
 }
 #endif
 
+void *androidGLgetProcAddress(const char *name) {
+	// This exists since Android 2.3 (API Level 9)
+	return (void *)eglGetProcAddress(name);
+}
+
 OSystem_Android::OSystem_Android(int audio_sample_rate, int audio_buffer_size) :
 	_audio_sample_rate(audio_sample_rate),
 	_audio_buffer_size(audio_buffer_size),

backends/platform/android/android.h

@@ -93,6 +93,8 @@ extern void checkGlError(const char *expr, const char *file, int line);
 #define GLTHREADCHECK do {  } while (false)
 #endif
 
+void *androidGLgetProcAddress(const char *name);
+
 class OSystem_Android : public ModularGraphicsBackend, Common::EventSource {
 private:
 	// passed from the dark side

backends/platform/android3d/android.cpp

@@ -40,6 +40,7 @@
 // for the Android port
 #define FORBIDDEN_SYMBOL_EXCEPTION_printf
 
+#include <EGL/egl.h>
 #include <sys/time.h>
 #include <sys/resource.h>
 #include <sys/system_properties.h>
@@ -118,6 +119,11 @@ void checkGlError(const char *expr, const char *file, int line) {
 }
 #endif
 
+void *androidGLgetProcAddress(const char *name) {
+       // This exists since Android 2.3 (API Level 9)
+       return (void *)eglGetProcAddress(name);
+}
+
 OSystem_Android::OSystem_Android(int audio_sample_rate, int audio_buffer_size) :
 	_audio_sample_rate(audio_sample_rate),
 	_audio_buffer_size(audio_buffer_size),

backends/platform/android3d/android.h

@@ -100,6 +100,8 @@ extern void checkGlError(const char *expr, const char *file, int line);
 #define GLTHREADCHECK do {  } while (false)
 #endif
 
+void *androidGLgetProcAddress(const char *name);
+
 class OSystem_Android : public ModularGraphicsBackend, Common::EventSource {
 private:
 	// passed from the dark side

backends/platform/android3d/graphics.h

@@ -114,8 +114,6 @@ protected:
 
 	void refreshScreen();
 
-	void *getProcAddress(const char *name) const;
-
 private:
 	void setCursorPaletteInternal(const byte *colors, uint start, uint num);
 	void disableCursorPalette();

configure

@@ -5334,10 +5334,12 @@ if test "$_opengl_mode" != none ; then
 		android)
 			# We require API level 16 while GLES2 APIs have been added in level 8 so we are safe for compilation
 			_opengl_mode=gles2
+			_opengl_glad=yes
 			;;
 		android3d)
 			# We require API level 16 while GLES2 APIs have been added in level 8 so we are safe for compilation
 			_opengl_mode=gles2
+			_opengl_glad=yes
 			;;
 		openpandora)
 			# Enable GLES only if user explicitely requested it
@@ -6125,7 +6127,7 @@ case $_host_os in
 		system_libs=''
 		for lib in $LIBS; do
 			case $lib in
-			-lz|-lm|-ldl|-lGLESv2)
+			-lz|-lm|-ldl)
 				system_libs="$system_libs $lib"
 				;;
 			*)
@@ -6137,7 +6139,7 @@ case $_host_os in
 		# -lgcc is carefully placed here - we want to catch
 		# all toolchain symbols in *our* libraries rather
 		# than pick up anything unhygenic from the Android libs.
-		LIBS="-Wl,-Bstatic $static_libs -Wl,-Bdynamic -lgcc $system_libs -llog -landroid -ljnigraphics -lGLESv2"
+		LIBS="-Wl,-Bstatic $static_libs -Wl,-Bdynamic -lgcc $system_libs -llog -landroid -ljnigraphics -lEGL"
 		;;
 	ds)
 		# Moved -Wl,--gc-sections here to avoid it interfering with the library checks

graphics/opengl/context.cpp

@@ -38,6 +38,15 @@
 static GLADapiproc loadFunc(void *userptr, const char *name) {
 	return (GLADapiproc)SDL_GL_GetProcAddress(name);
 }
+
+#elif defined(__ANDROID__)
+// To keep includes light, don't include EGL here and don't include Android headers
+void *androidGLgetProcAddress(const char *name);
+
+static GLADapiproc loadFunc(void *userptr, const char *name) {
+	return (GLADapiproc)androidGLgetProcAddress(name);
+}
+
 #else
 #error Not implemented
 #endif