Add native window/taskbar icon support for Windows and macOS.

Co-authored-by: Markus Törnqvist <mjt@nysv.org>

11 files changed, 209 insertions, 2 deletions

diff --git a/core/bind/core_bind.cpp b/core/bind/core_bind.cpp
index ba595b9627..d571b4a479 100644
--- a/core/bind/core_bind.cpp
+++ b/core/bind/core_bind.cpp
@@ -611,6 +611,11 @@ uint64_t _OS::get_dynamic_memory_usage() const {
 	return OS::get_singleton()->get_dynamic_memory_usage();
 }
 
+void _OS::set_native_icon(const String &p_filename) {
+
+	OS::get_singleton()->set_native_icon(p_filename);
+}
+
 void _OS::set_icon(const Ref<Image> &p_icon) {
 
 	OS::get_singleton()->set_icon(p_icon);
@@ -1199,6 +1204,7 @@ void _OS::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("get_system_time_secs"), &_OS::get_system_time_secs);
 	ClassDB::bind_method(D_METHOD("get_system_time_msecs"), &_OS::get_system_time_msecs);
 
+	ClassDB::bind_method(D_METHOD("set_native_icon", "filename"), &_OS::set_native_icon);
 	ClassDB::bind_method(D_METHOD("set_icon", "icon"), &_OS::set_icon);
 
 	ClassDB::bind_method(D_METHOD("get_exit_code"), &_OS::get_exit_code);
diff --git a/core/bind/core_bind.h b/core/bind/core_bind.h
index 2906de4a4a..cf2014ef27 100644
--- a/core/bind/core_bind.h
+++ b/core/bind/core_bind.h
@@ -275,6 +275,7 @@ public:
 
 	void set_use_file_access_save_and_swap(bool p_enable);
 
+	void set_native_icon(const String &p_filename);
 	void set_icon(const Ref<Image> &p_icon);
 
 	int get_exit_code() const;
diff --git a/core/os/os.cpp b/core/os/os.cpp
index ea378c9e83..1a3c9ac5f8 100644
--- a/core/os/os.cpp
+++ b/core/os/os.cpp
@@ -465,6 +465,9 @@ void OS::_ensure_user_data_dir() {
 	memdelete(da);
 }
 
+void OS::set_native_icon(const String &p_filename) {
+}
+
 void OS::set_icon(const Ref<Image> &p_icon) {
 }
 
diff --git a/core/os/os.h b/core/os/os.h
index 07865b636e..4f6a539e78 100644
--- a/core/os/os.h
+++ b/core/os/os.h
@@ -451,6 +451,7 @@ public:
 	virtual void make_rendering_thread();
 	virtual void swap_buffers();
 
+	virtual void set_native_icon(const String &p_filename);
 	virtual void set_icon(const Ref<Image> &p_icon);
 
 	virtual int get_exit_code() const;
diff --git a/doc/classes/OS.xml b/doc/classes/OS.xml
index c9c83bc0e0..ec2ee78701 100644
--- a/doc/classes/OS.xml
+++ b/doc/classes/OS.xml
@@ -697,7 +697,19 @@
 			<argument index="0" name="icon" type="Image">
 			</argument>
 			<description>
-				Sets the game's icon.
+				Sets the game's icon using an [Image] resource.
+				The same image is used for window caption, taskbar/dock and window selection dialog. Image is scaled as needed.
+			</description>
+		</method>
+		<method name="set_native_icon">
+			<return type="void">
+			</return>
+			<argument index="0" name="filename" type="String">
+			</argument>
+			<description>
+				Sets the game's icon using a multi-size platform-specific icon file ([code]*.ico[/code] on Windows and [code]*.icns[/code] on macOS).
+				Appropriate size sub-icons are used for window caption, taskbar/dock and window selection dialog.
+				Note: This method is only implemented on macOS and Windows.
 			</description>
 		</method>
 		<method name="set_ime_active">
diff --git a/editor/editor_export.cpp b/editor/editor_export.cpp
index 6751e58bb2..af4d2ea37d 100644
--- a/editor/editor_export.cpp
+++ b/editor/editor_export.cpp
@@ -692,6 +692,10 @@ Error EditorExportPlatform::export_project_files(const Ref<EditorExportPreset> &
 		}
 	}
 
+	//add native icons to non-resource include list
+	_edit_filter_list(paths, String("*.icns"), false);
+	_edit_filter_list(paths, String("*.ico"), false);
+
 	_edit_filter_list(paths, p_preset->get_include_filter(), false);
 	_edit_filter_list(paths, p_preset->get_exclude_filter(), true);
 
diff --git a/main/main.cpp b/main/main.cpp
index da77962c8a..9a156102e5 100644
--- a/main/main.cpp
+++ b/main/main.cpp
@@ -1189,6 +1189,12 @@ Error Main::setup2(Thread::ID p_main_tid_override) {
 	GLOBAL_DEF("application/config/icon", String());
 	ProjectSettings::get_singleton()->set_custom_property_info("application/config/icon", PropertyInfo(Variant::STRING, "application/config/icon", PROPERTY_HINT_FILE, "*.png,*.webp"));
 
+	GLOBAL_DEF("application/config/macos_native_icon", String());
+	ProjectSettings::get_singleton()->set_custom_property_info("application/config/macos_native_icon", PropertyInfo(Variant::STRING, "application/config/macos_native_icon", PROPERTY_HINT_FILE, "*.icns"));
+
+	GLOBAL_DEF("application/config/windows_native_icon", String());
+	ProjectSettings::get_singleton()->set_custom_property_info("application/config/windows_native_icon", PropertyInfo(Variant::STRING, "application/config/windows_native_icon", PROPERTY_HINT_FILE, "*.ico"));
+
 	InputDefault *id = Object::cast_to<InputDefault>(Input::get_singleton());
 	if (id) {
 		if (bool(GLOBAL_DEF("input_devices/pointing/emulate_touch_from_mouse", false)) && !(editor || project_manager)) {
@@ -1739,8 +1745,24 @@ bool Main::start() {
 				ERR_FAIL_COND_V(!scene, false)
 				sml->add_current_scene(scene);
 
+#ifdef OSX_ENABLED
+				String mac_iconpath = GLOBAL_DEF("application/config/macos_native_icon", "Variant()");
+				if (mac_iconpath != "") {
+					OS::get_singleton()->set_native_icon(mac_iconpath);
+					hasicon = true;
+				}
+#endif
+
+#ifdef WINDOWS_ENABLED
+				String win_iconpath = GLOBAL_DEF("application/config/windows_native_icon", "Variant()");
+				if (win_iconpath != "") {
+					OS::get_singleton()->set_native_icon(win_iconpath);
+					hasicon = true;
+				}
+#endif
+
 				String iconpath = GLOBAL_DEF("application/config/icon", "Variant()");
-				if (iconpath != "") {
+				if ((iconpath != "") && (!hasicon)) {
 					Ref<Image> icon;
 					icon.instance();
 					if (ImageLoader::load_image(iconpath, icon) == OK) {
diff --git a/platform/osx/os_osx.h b/platform/osx/os_osx.h
index d2a6f38b01..212966af11 100644
--- a/platform/osx/os_osx.h
+++ b/platform/osx/os_osx.h
@@ -186,6 +186,7 @@ public:
 	virtual Size2 get_window_size() const;
 	virtual Size2 get_real_window_size() const;
 
+	virtual void set_native_icon(const String &p_filename);
 	virtual void set_icon(const Ref<Image> &p_icon);
 
 	virtual MainLoop *get_main_loop() const;
diff --git a/platform/osx/os_osx.mm b/platform/osx/os_osx.mm
index fc97bd4a20..113c6636f0 100644
--- a/platform/osx/os_osx.mm
+++ b/platform/osx/os_osx.mm
@@ -1858,6 +1858,31 @@ void OS_OSX::set_window_title(const String &p_title) {
 	[window_object setTitle:[NSString stringWithUTF8String:p_title.utf8().get_data()]];
 }
 
+void OS_OSX::set_native_icon(const String &p_filename) {
+
+	FileAccess *f = FileAccess::open(p_filename, FileAccess::READ);
+	ERR_FAIL_COND(!f);
+
+	Vector<uint8_t> data;
+	uint32_t len = f->get_len();
+	data.resize(len);
+	f->get_buffer((uint8_t *)&data.write[0], len);
+	memdelete(f);
+
+	NSData *icon_data = [[[NSData alloc] initWithBytes:&data.write[0] length:len] autorelease];
+	if (!icon_data) {
+		ERR_EXPLAIN("Error reading icon data");
+		ERR_FAIL();
+	}
+	NSImage *icon = [[[NSImage alloc] initWithData:icon_data] autorelease];
+	if (!icon) {
+		ERR_EXPLAIN("Error loading icon");
+		ERR_FAIL();
+	}
+
+	[NSApp setApplicationIconImage:icon];
+}
+
 void OS_OSX::set_icon(const Ref<Image> &p_icon) {
 
 	Ref<Image> img = p_icon;
diff --git a/platform/windows/os_windows.cpp b/platform/windows/os_windows.cpp
index 4c6e4e96b5..e3494a1dbf 100644
--- a/platform/windows/os_windows.cpp
+++ b/platform/windows/os_windows.cpp
@@ -2577,6 +2577,117 @@ String OS_Windows::get_executable_path() const {
 	return s;
 }
 
+void OS_Windows::set_native_icon(const String &p_filename) {
+
+	FileAccess *f = FileAccess::open(p_filename, FileAccess::READ);
+	ERR_FAIL_COND(!f);
+
+	ICONDIR *icon_dir = (ICONDIR *)memalloc(sizeof(ICONDIR));
+	int pos = 0;
+
+	icon_dir->idReserved = f->get_32();
+	pos += sizeof(WORD);
+	f->seek(pos);
+
+	icon_dir->idType = f->get_32();
+	pos += sizeof(WORD);
+	f->seek(pos);
+
+	if (icon_dir->idType != 1) {
+		ERR_EXPLAIN("Invalid icon file format!");
+		ERR_FAIL();
+	}
+
+	icon_dir->idCount = f->get_32();
+	pos += sizeof(WORD);
+	f->seek(pos);
+
+	icon_dir = (ICONDIR *)memrealloc(icon_dir, 3 * sizeof(WORD) + icon_dir->idCount * sizeof(ICONDIRENTRY));
+	f->get_buffer((uint8_t *)&icon_dir->idEntries[0], icon_dir->idCount * sizeof(ICONDIRENTRY));
+
+	int small_icon_index = -1; // Select 16x16 with largest color count
+	int small_icon_cc = 0;
+	int big_icon_index = -1; // Select largest
+	int big_icon_width = 16;
+	int big_icon_cc = 0;
+
+	for (int i = 0; i < icon_dir->idCount; i++) {
+		int colors = (icon_dir->idEntries[i].bColorCount == 0) ? 32768 : icon_dir->idEntries[i].bColorCount;
+		int width = (icon_dir->idEntries[i].bWidth == 0) ? 256 : icon_dir->idEntries[i].bWidth;
+		if (width == 16) {
+			if (colors >= small_icon_cc) {
+				small_icon_index = i;
+				small_icon_cc = colors;
+			}
+		}
+		if (width >= big_icon_width) {
+			if (colors >= big_icon_cc) {
+				big_icon_index = i;
+				big_icon_width = width;
+				big_icon_cc = colors;
+			}
+		}
+	}
+
+	if (big_icon_index == -1) {
+		ERR_EXPLAIN("No valid icons found!");
+		ERR_FAIL();
+	}
+
+	if (small_icon_index == -1) {
+		WARN_PRINTS("No small icon found, reusing " + itos(big_icon_width) + "x" + itos(big_icon_width) + " @" + itos(big_icon_cc) + " icon!");
+		small_icon_index = big_icon_index;
+		small_icon_cc = big_icon_cc;
+	}
+
+	// Read the big icon
+	DWORD bytecount_big = icon_dir->idEntries[big_icon_index].dwBytesInRes;
+	Vector<uint8_t> data_big;
+	data_big.resize(bytecount_big);
+	pos = icon_dir->idEntries[big_icon_index].dwImageOffset;
+	f->seek(pos);
+	f->get_buffer((uint8_t *)&data_big.write[0], bytecount_big);
+	HICON icon_big = CreateIconFromResource((PBYTE)&data_big.write[0], bytecount_big, TRUE, 0x00030000);
+	if (!icon_big) {
+		ERR_EXPLAIN("Could not create " + itos(big_icon_width) + "x" + itos(big_icon_width) + " @" + itos(big_icon_cc) + " icon, error: " + format_error_message(GetLastError()));
+		ERR_FAIL();
+	}
+
+	// Read the small icon
+	DWORD bytecount_small = icon_dir->idEntries[small_icon_index].dwBytesInRes;
+	Vector<uint8_t> data_small;
+	data_small.resize(bytecount_small);
+	pos = icon_dir->idEntries[small_icon_index].dwImageOffset;
+	f->seek(pos);
+	f->get_buffer((uint8_t *)&data_small.write[0], bytecount_small);
+	HICON icon_small = CreateIconFromResource((PBYTE)&data_small.write[0], bytecount_small, TRUE, 0x00030000);
+	if (!icon_small) {
+		ERR_EXPLAIN("Could not create 16x16 @" + itos(small_icon_cc) + " icon, error: " + format_error_message(GetLastError()));
+		ERR_FAIL();
+	}
+
+	// Online tradition says to be sure last error is cleared and set the small icon first
+	int err = 0;
+	SetLastError(err);
+
+	SendMessage(hWnd, WM_SETICON, ICON_SMALL, (LPARAM)icon_small);
+	err = GetLastError();
+	if (err) {
+		ERR_EXPLAIN("Error setting ICON_SMALL: " + format_error_message(err));
+		ERR_FAIL();
+	}
+
+	SendMessage(hWnd, WM_SETICON, ICON_BIG, (LPARAM)icon_big);
+	err = GetLastError();
+	if (err) {
+		ERR_EXPLAIN("Error setting ICON_BIG: " + format_error_message(err));
+		ERR_FAIL();
+	}
+
+	memdelete(f);
+	memdelete(icon_dir);
+}
+
 void OS_Windows::set_icon(const Ref<Image> &p_icon) {
 
 	ERR_FAIL_COND(!p_icon.is_valid());
diff --git a/platform/windows/os_windows.h b/platform/windows/os_windows.h
index 59aeb01b51..0aacbcb9ff 100644
--- a/platform/windows/os_windows.h
+++ b/platform/windows/os_windows.h
@@ -58,6 +58,25 @@
 /**
 	@author Juan Linietsky <reduzio@gmail.com>
 */
+
+typedef struct {
+	BYTE bWidth; // Width, in pixels, of the image
+	BYTE bHeight; // Height, in pixels, of the image
+	BYTE bColorCount; // Number of colors in image (0 if >=8bpp)
+	BYTE bReserved; // Reserved ( must be 0)
+	WORD wPlanes; // Color Planes
+	WORD wBitCount; // Bits per pixel
+	DWORD dwBytesInRes; // How many bytes in this resource?
+	DWORD dwImageOffset; // Where in the file is this image?
+} ICONDIRENTRY, *LPICONDIRENTRY;
+
+typedef struct {
+	WORD idReserved; // Reserved (must be 0)
+	WORD idType; // Resource Type (1 for icons)
+	WORD idCount; // How many images?
+	ICONDIRENTRY idEntries[1]; // An entry for each image (idCount of 'em)
+} ICONDIR, *LPICONDIR;
+
 class JoypadWindows;
 class OS_Windows : public OS {
 
@@ -276,6 +295,8 @@ public:
 	CursorShape get_cursor_shape() const;
 	virtual void set_custom_mouse_cursor(const RES &p_cursor, CursorShape p_shape, const Vector2 &p_hotspot);
 	void GetMaskBitmaps(HBITMAP hSourceBitmap, COLORREF clrTransparent, OUT HBITMAP &hAndMaskBitmap, OUT HBITMAP &hXorMaskBitmap);
+
+	void set_native_icon(const String &p_filename);
 	void set_icon(const Ref<Image> &p_icon);
 
 	virtual String get_executable_path() const;