Improve 2D editor zoom logic

- Add 1-5 shortcuts to zoom between 100% and 1600% quickly
  (similar to GIMP).
- When holding down Alt, go through integer zoom values if above 100%
  or fractional zoom values with integer denominators if below 100%
  (50%, ~33.3%, 25%, …).

1 files changed, 30 insertions, 4 deletions

diff --git a/editor/plugins/canvas_item_editor_plugin.cpp b/editor/plugins/canvas_item_editor_plugin.cpp
index 7282475ddf..94cd8ce17d 100644
--- a/editor/plugins/canvas_item_editor_plugin.cpp
+++ b/editor/plugins/canvas_item_editor_plugin.cpp
@@ -1149,8 +1149,9 @@ bool CanvasItemEditor::_gui_input_zoom_or_pan(const Ref<InputEvent> &p_event, bo
 				view_offset.y += int(EditorSettings::get_singleton()->get("editors/2d/pan_speed")) / zoom * b->get_factor();
 				update_viewport();
 			} else {
-				zoom_widget->set_zoom_by_increments(-1);
-				if (b->get_factor() != 1.f) {
+				zoom_widget->set_zoom_by_increments(-1, Input::get_singleton()->is_key_pressed(KEY_ALT));
+				if (!Math::is_equal_approx(b->get_factor(), 1.0f)) {
+					// Handle high-precision (analog) scrolling.
 					zoom_widget->set_zoom(zoom * ((zoom_widget->get_zoom() / zoom - 1.f) * b->get_factor() + 1.f));
 				}
 				_zoom_on_position(zoom_widget->get_zoom(), b->get_position());
@@ -1164,8 +1165,9 @@ bool CanvasItemEditor::_gui_input_zoom_or_pan(const Ref<InputEvent> &p_event, bo
 				view_offset.y -= int(EditorSettings::get_singleton()->get("editors/2d/pan_speed")) / zoom * b->get_factor();
 				update_viewport();
 			} else {
-				zoom_widget->set_zoom_by_increments(1);
-				if (b->get_factor() != 1.f) {
+				zoom_widget->set_zoom_by_increments(1, Input::get_singleton()->is_key_pressed(KEY_ALT));
+				if (!Math::is_equal_approx(b->get_factor(), 1.0f)) {
+					// Handle high-precision (analog) scrolling.
 					zoom_widget->set_zoom(zoom * ((zoom_widget->get_zoom() / zoom - 1.f) * b->get_factor() + 1.f));
 				}
 				_zoom_on_position(zoom_widget->get_zoom(), b->get_position());
@@ -1194,6 +1196,20 @@ bool CanvasItemEditor::_gui_input_zoom_or_pan(const Ref<InputEvent> &p_event, bo
 
 	Ref<InputEventKey> k = p_event;
 	if (k.is_valid()) {
+		if (k->is_pressed()) {
+			if (ED_GET_SHORTCUT("canvas_item_editor/zoom_100_percent")->is_shortcut(p_event)) {
+				_update_zoom(1.0 * MAX(1, EDSCALE));
+			} else if (ED_GET_SHORTCUT("canvas_item_editor/zoom_200_percent")->is_shortcut(p_event)) {
+				_update_zoom(2.0 * MAX(1, EDSCALE));
+			} else if (ED_GET_SHORTCUT("canvas_item_editor/zoom_400_percent")->is_shortcut(p_event)) {
+				_update_zoom(4.0 * MAX(1, EDSCALE));
+			} else if (ED_GET_SHORTCUT("canvas_item_editor/zoom_800_percent")->is_shortcut(p_event)) {
+				_update_zoom(8.0 * MAX(1, EDSCALE));
+			} else if (ED_GET_SHORTCUT("canvas_item_editor/zoom_1600_percent")->is_shortcut(p_event)) {
+				_update_zoom(16.0 * MAX(1, EDSCALE));
+			}
+		}
+
 		bool is_pan_key = pan_view_shortcut.is_valid() && pan_view_shortcut->is_shortcut(p_event);
 
 		if (is_pan_key && (EditorSettings::get_singleton()->get("editors/2d/simple_panning") || drag_type != DRAG_NONE)) {
@@ -5610,6 +5626,16 @@ CanvasItemEditor::CanvasItemEditor(EditorNode *p_editor) {
 	skeleton_menu->get_popup()->set_item_checked(skeleton_menu->get_popup()->get_item_index(SKELETON_SHOW_BONES), true);
 	singleton = this;
 
+	// To ensure that scripts can parse the list of shortcuts correctly, we have to define
+	// those shortcuts one by one.
+	// Resetting zoom to 100% is a duplicate shortcut of `canvas_item_editor/reset_zoom`,
+	// but it ensures both 1 and Ctrl + 0 can be used to reset zoom.
+	ED_SHORTCUT("canvas_item_editor/zoom_100_percent", TTR("Zoom To 100%"), KEY_1);
+	ED_SHORTCUT("canvas_item_editor/zoom_200_percent", TTR("Zoom To 200%"), KEY_2);
+	ED_SHORTCUT("canvas_item_editor/zoom_400_percent", TTR("Zoom To 400%"), KEY_3);
+	ED_SHORTCUT("canvas_item_editor/zoom_800_percent", TTR("Zoom To 800%"), KEY_4);
+	ED_SHORTCUT("canvas_item_editor/zoom_1600_percent", TTR("Zoom To 1600%"), KEY_5);
+
 	set_process_unhandled_key_input(true);
 
 	// Update the menus' checkboxes