[HTML5] Make GDNative support feature-based.

This is suboptimal as it requires adding an extra compile flag, but
rewriting how feature tags work is beyond the scope of this work.

modules/gdnative/gdnative_library_editor_plugin.cpp

@@ -310,7 +310,7 @@ GDNativeLibraryEditor::GDNativeLibraryEditor() {
 
 		NativePlatformConfig platform_html5;
 		platform_html5.name = "HTML5";
-		platform_html5.entries.push_back("web");
+		platform_html5.entries.push_back("wasm32");
 		platform_html5.library_extension = "*.wasm";
 		platforms["HTML5"] = platform_html5;
 

platform/javascript/SCsub

@@ -52,6 +52,7 @@ if env["gdnative_enabled"]:
 
     # The side library, containing all Godot code.
     wasm_env = env.Clone()
+    wasm_env.Append(CPPDEFINES=["WASM_GDNATIVE"])  # So that OS knows it can run GDNative libraries.
     wasm_env.Append(CCFLAGS=["-s", "SIDE_MODULE=2"])
     wasm_env.Append(LINKFLAGS=["-s", "SIDE_MODULE=2"])
     wasm = wasm_env.add_program("#bin/godot.side${PROGSUFFIX}.wasm", javascript_files)

platform/javascript/export/export.cpp

@@ -330,6 +330,12 @@ void EditorExportPlatformJavaScript::get_preset_features(const Ref<EditorExportP
 			r_features->push_back("etc2");
 		}
 	}
+	ExportMode mode = (ExportMode)(int)p_preset->get("variant/export_type");
+	if (mode == EXPORT_MODE_THREADS) {
+		r_features->push_back("threads");
+	} else if (mode == EXPORT_MODE_GDNATIVE) {
+		r_features->push_back("wasm32");
+	}
 }
 
 void EditorExportPlatformJavaScript::get_export_options(List<ExportOption> *r_options) {

platform/javascript/os_javascript.cpp

@@ -128,12 +128,24 @@ int OS_JavaScript::get_process_id() const {
 }
 
 bool OS_JavaScript::_check_internal_feature_support(const String &p_feature) {
-	if (p_feature == "HTML5" || p_feature == "web")
+	if (p_feature == "HTML5" || p_feature == "web") {
 		return true;
+	}
 
 #ifdef JAVASCRIPT_EVAL_ENABLED
-	if (p_feature == "JavaScript")
+	if (p_feature == "JavaScript") {
+		return true;
+	}
+#endif
+#ifndef NO_THREADS
+	if (p_feature == "threads") {
 		return true;
+	}
+#endif
+#if WASM_GDNATIVE
+	if (p_feature == "wasm32") {
+		return true;
+	}
 #endif
 
 	return false;