[feat] Save color palette as resources to reuse later

godotengine/godot-proposals#7946

The lack of a palette library slows down development time because swatches contain many colors that may not match the mood an artist is trying to achieve. This can hinder their workflow as they search for the right color within a large set of mostly irrelevant options.

scene/gui/color_picker.cpp

@@ -35,6 +35,7 @@
 #include "core/math/color.h"
 #include "core/os/keyboard.h"
 #include "core/os/os.h"
+#include "core/string/ustring.h"
 #include "scene/gui/color_mode.h"
 #include "scene/gui/margin_container.h"
 #include "scene/resources/image_texture.h"
@@ -75,6 +76,8 @@ void ColorPicker::_notification(int p_what) {
 			_update_drop_down_arrow(btn_preset->is_pressed(), btn_preset);
 			_update_drop_down_arrow(btn_recent_preset->is_pressed(), btn_recent_preset);
 			btn_add_preset->set_icon(theme_cache.add_preset);
+			load_swatches->set_icon(get_theme_icon(SNAME("folder"), SNAME("FileDialog")));
+			save_swatches->set_icon(get_theme_icon(SNAME("folder"), SNAME("FileDialog")));
 
 			btn_pick->set_custom_minimum_size(Size2(28 * theme_cache.base_scale, 0));
 			btn_shape->set_custom_minimum_size(Size2(28 * theme_cache.base_scale, 0));
@@ -774,6 +777,69 @@ void ColorPicker::_add_recent_preset_button(int p_size, const Color &p_color) {
 	btn_preset_new->connect("toggled", callable_mp(this, &ColorPicker::_recent_preset_pressed).bind(btn_preset_new));
 }
 
+void ColorPicker::_load_palette() {
+	List<String> extensions;
+	ResourceLoader::get_recognized_extensions_for_type("Resource", &extensions);
+
+	file_dialog->set_title(RTR("Load Palette"));
+	file_dialog->clear_filters();
+	for (const String &K : extensions) {
+		file_dialog->add_filter("*." + K);
+	}
+
+	file_dialog->set_file_mode(FileDialog::FILE_MODE_OPEN_FILE);
+	file_dialog->set_access(FileDialog::ACCESS_USERDATA);
+	file_dialog->set_current_file("");
+	file_dialog->popup_centered_ratio();
+}
+
+void ColorPicker::_save_palette() {
+	List<String> extensions;
+	ResourceLoader::get_recognized_extensions_for_type("Resource", &extensions);
+
+	file_dialog->set_title(RTR("Save Palette"));
+	file_dialog->clear_filters();
+	for (const String &K : extensions) {
+		file_dialog->add_filter("*." + K);
+	}
+
+	file_dialog->set_file_mode(FileDialog::FILE_MODE_SAVE_FILE);
+	file_dialog->set_access(FileDialog::ACCESS_USERDATA);
+	file_dialog->popup_centered_ratio();
+}
+
+void ColorPicker::_palette_file_selected(const String &p_path) {
+	switch (file_dialog->get_file_mode()) {
+		case FileDialog::FileMode::FILE_MODE_OPEN_FILE: {
+			Ref<FileAccess> file_access = FileAccess::open(p_path, FileAccess::READ);
+			ERR_FAIL_COND_MSG(file_access.is_null(), vformat("Cannot open file to Read."));
+			preset_cache.clear();
+			presets.clear();
+
+			PackedColorArray saved_presets = file_access->get_var();
+			for (int i = 0; i < saved_presets.size(); ++i) {
+				preset_cache.push_back(saved_presets[i]);
+				presets.push_back(saved_presets[i]);
+			}
+
+			_update_presets();
+		} break;
+		case FileDialog::FileMode::FILE_MODE_OPEN_FILES:
+			break;
+		case FileDialog::FileMode::FILE_MODE_OPEN_DIR:
+			break;
+		case FileDialog::FileMode::FILE_MODE_OPEN_ANY:
+			break;
+		case FileDialog::FileMode::FILE_MODE_SAVE_FILE: {
+			Ref<FileAccess> file_access = FileAccess::open(p_path, FileAccess::WRITE);
+			ERR_FAIL_COND_MSG(file_access.is_null(), vformat("Cannot open file to write."));
+			file_access->store_var(get_presets());
+		} break;
+		default:
+			break;
+	}
+}
+
 void ColorPicker::_show_hide_preset(const bool &p_is_btn_pressed, Button *p_btn_preset, Container *p_preset_container) {
 	if (p_is_btn_pressed) {
 		p_preset_container->show();
@@ -1809,6 +1875,10 @@ void ColorPicker::_bind_methods() {
 }
 
 ColorPicker::ColorPicker() {
+	file_dialog = memnew(FileDialog);
+	add_child(file_dialog);
+	file_dialog->connect("file_selected", callable_mp(this, &ColorPicker::_palette_file_selected));
+
 	internal_margin = memnew(MarginContainer);
 	add_child(internal_margin, false, INTERNAL_MODE_FRONT);
 
@@ -1991,14 +2061,38 @@ ColorPicker::ColorPicker() {
 
 	preset_group.instantiate();
 
+	HBoxContainer *swatch_box = memnew(HBoxContainer);
+	swatch_box->set_h_size_flags(SIZE_EXPAND_FILL);
+	real_vbox->add_child(swatch_box);
+
 	btn_preset = memnew(Button);
 	btn_preset->set_text("Swatches");
 	btn_preset->set_flat(true);
 	btn_preset->set_toggle_mode(true);
 	btn_preset->set_focus_mode(FOCUS_NONE);
 	btn_preset->set_text_alignment(HORIZONTAL_ALIGNMENT_LEFT);
 	btn_preset->connect("toggled", callable_mp(this, &ColorPicker::_show_hide_preset).bind(btn_preset, preset_container));
-	real_vbox->add_child(btn_preset);
+	swatch_box->add_child(btn_preset);
+
+	HBoxContainer *padding_box = memnew(HBoxContainer);
+	padding_box->set_h_size_flags(SIZE_EXPAND_FILL);
+	swatch_box->add_child(padding_box);
+
+	load_swatches = memnew(Button);
+	load_swatches->set_flat(true);
+	load_swatches->set_tooltip_text(RTR("Load existing color palette"));
+	load_swatches->set_toggle_mode(true);
+	load_swatches->set_focus_mode(FOCUS_NONE);
+	load_swatches->connect("pressed", callable_mp(this, &ColorPicker::_load_palette));
+	swatch_box->add_child(load_swatches);
+
+	save_swatches = memnew(Button);
+	save_swatches->set_flat(true);
+	save_swatches->set_tooltip_text(RTR("Save the current color palette to reuse later"));
+	save_swatches->set_toggle_mode(true);
+	save_swatches->set_focus_mode(FOCUS_NONE);
+	save_swatches->connect("pressed", callable_mp(this, &ColorPicker::_save_palette));
+	swatch_box->add_child(save_swatches);
 
 	real_vbox->add_child(preset_container);
 

scene/gui/color_picker.h

@@ -35,6 +35,7 @@
 #include "scene/gui/box_container.h"
 #include "scene/gui/button.h"
 #include "scene/gui/control.h"
+#include "scene/gui/file_dialog.h"
 #include "scene/gui/grid_container.h"
 #include "scene/gui/label.h"
 #include "scene/gui/line_edit.h"
@@ -134,6 +135,9 @@ class ColorPicker : public VBoxContainer {
 	Label *picker_preview_label = nullptr;
 	Ref<StyleBoxFlat> picker_preview_style_box;
 	Color picker_color;
+	FileDialog *file_dialog = nullptr;
+	Button *load_swatches = nullptr;
+	Button *save_swatches = nullptr;
 
 	MarginContainer *internal_margin = nullptr;
 	Control *uv_edit = nullptr;
@@ -286,6 +290,9 @@ class ColorPicker : public VBoxContainer {
 	inline int _get_preset_size();
 	void _add_preset_button(int p_size, const Color &p_color);
 	void _add_recent_preset_button(int p_size, const Color &p_color);
+	void _save_palette();
+	void _load_palette();
+	void _palette_file_selected(const String &p_path);
 
 	void _show_hide_preset(const bool &p_is_btn_pressed, Button *p_btn_preset, Container *p_preset_container);
 	void _update_drop_down_arrow(const bool &p_is_btn_pressed, Button *p_btn_preset);