Refactor shape gizmo interactivity to support future shape tools (#2748)

* impl GizmoHandlerTrait,Gizmo-manager and add comments

* Code review

---------

Co-authored-by: Keavon Chambers <keavon@keavon.com>

Author: 0SlowPoke0

editor/src/consts.rs

@@ -122,8 +122,8 @@ pub const DEFAULT_BRUSH_SIZE: f64 = 20.;
 // GIZMOS
 pub const POINT_RADIUS_HANDLE_SNAP_THRESHOLD: f64 = 8.;
 pub const POINT_RADIUS_HANDLE_SEGMENT_THRESHOLD: f64 = 7.9;
-pub const NUMBER_OF_POINTS_HANDLE_SPOKE_EXTENSION: f64 = 1.2;
-pub const NUMBER_OF_POINTS_HANDLE_SPOKE_LENGTH: f64 = 10.;
+pub const NUMBER_OF_POINTS_DIAL_SPOKE_EXTENSION: f64 = 1.2;
+pub const NUMBER_OF_POINTS_DIAL_SPOKE_LENGTH: f64 = 10.;
 pub const GIZMO_HIDE_THRESHOLD: f64 = 20.;
 
 // SCROLLBARS

editor/src/messages/portfolio/document/document_message_handler.rs

@@ -1624,7 +1624,7 @@ impl DocumentMessageHandler {
 					subpath.is_inside_subpath(&viewport_polygon, None, None)
 				}
 				ClickTargetType::FreePoint(point) => {
-					let mut point = point.clone();
+					let mut point = *point;
 					point.apply_transform(layer_transform);
 					viewport_polygon.contains_point(point.position)
 				}
@@ -3346,9 +3346,9 @@ mod document_message_handler_tests {
 		let rect_bbox_after = document.metadata().bounding_box_viewport(rect_layer).unwrap();
 
 		// Verifing the rectangle maintains approximately the same position in viewport space
-		let before_center = (rect_bbox_before[0] + rect_bbox_before[1]) / 2.; // TODO: Should be: DVec2(0.0, -25.0), regression (#2688) causes it to be: DVec2(100.0, 25.0)
-		let after_center = (rect_bbox_after[0] + rect_bbox_after[1]) / 2.; // TODO:    Should be: DVec2(0.0, -25.0), regression (#2688) causes it to be: DVec2(200.0, 75.0)
-		let distance = before_center.distance(after_center); // TODO:                    Should be: 0.0,               regression (#2688) causes it to be: 111.80339887498948
+		let before_center = (rect_bbox_before[0] + rect_bbox_before[1]) / 2.; // TODO: Should be: DVec2(0., -25.), regression (#2688) causes it to be: DVec2(100., 25.)
+		let after_center = (rect_bbox_after[0] + rect_bbox_after[1]) / 2.; // TODO:    Should be: DVec2(0., -25.), regression (#2688) causes it to be: DVec2(200., 75.)
+		let distance = before_center.distance(after_center); // TODO:                    Should be: 0.,               regression (#2688) causes it to be: 111.80339887498948
 
 		assert!(
 			distance < 1.,

editor/src/messages/tool/common_functionality/gizmos/gizmo_manager.rs

@@ -0,0 +1,246 @@
+use crate::messages::message::Message;
+use crate::messages::portfolio::document::overlays::utility_types::OverlayContext;
+use crate::messages::portfolio::document::utility_types::document_metadata::LayerNodeIdentifier;
+use crate::messages::prelude::{DocumentMessageHandler, InputPreprocessorMessageHandler};
+use crate::messages::tool::common_functionality::graph_modification_utils;
+use crate::messages::tool::common_functionality::shape_editor::ShapeState;
+use crate::messages::tool::common_functionality::shapes::polygon_shape::PolygonGizmoHandler;
+use crate::messages::tool::common_functionality::shapes::shape_utility::ShapeGizmoHandler;
+use crate::messages::tool::common_functionality::shapes::star_shape::StarGizmoHandler;
+use glam::DVec2;
+use std::collections::VecDeque;
+
+/// A unified enum wrapper around all available shape-specific gizmo handlers.
+///
+/// This abstraction allows `GizmoManager` to interact with different shape gizmos (like Star or Polygon)
+/// using a common interface without needing to know the specific shape type at compile time.
+///
+/// Each variant stores a concrete handler (e.g., `StarGizmoHandler`, `PolygonGizmoHandler`) that implements
+/// the shape-specific logic for rendering overlays, responding to input, and modifying shape parameters.
+#[derive(Clone, Debug, Default)]
+pub enum ShapeGizmoHandlers {
+	#[default]
+	None,
+	Star(StarGizmoHandler),
+	Polygon(PolygonGizmoHandler),
+}
+
+impl ShapeGizmoHandlers {
+	/// Returns the kind of shape the handler is managing, such as `"star"` or `"polygon"`.
+	/// Used for grouping logic and distinguishing between handler types at runtime.
+	pub fn kind(&self) -> &'static str {
+		match self {
+			Self::Star(_) => "star",
+			Self::Polygon(_) => "polygon",
+			Self::None => "none",
+		}
+	}
+
+	/// Dispatches interaction state updates to the corresponding shape-specific handler.
+	pub fn handle_state(&mut self, layer: LayerNodeIdentifier, mouse_position: DVec2, document: &DocumentMessageHandler, responses: &mut VecDeque<Message>) {
+		match self {
+			Self::Star(h) => h.handle_state(layer, mouse_position, document, responses),
+			Self::Polygon(h) => h.handle_state(layer, mouse_position, document, responses),
+			Self::None => {}
+		}
+	}
+
+	/// Checks if any interactive part of the gizmo is currently hovered.
+	pub fn is_any_gizmo_hovered(&self) -> bool {
+		match self {
+			Self::Star(h) => h.is_any_gizmo_hovered(),
+			Self::Polygon(h) => h.is_any_gizmo_hovered(),
+			Self::None => false,
+		}
+	}
+
+	/// Passes the click interaction to the appropriate gizmo handler if one is hovered.
+	pub fn handle_click(&mut self) {
+		match self {
+			Self::Star(h) => h.handle_click(),
+			Self::Polygon(h) => h.handle_click(),
+			Self::None => {}
+		}
+	}
+
+	/// Updates the gizmo state while the user is dragging a handle (e.g., adjusting radius).
+	pub fn handle_update(&mut self, drag_start: DVec2, document: &DocumentMessageHandler, input: &InputPreprocessorMessageHandler, responses: &mut VecDeque<Message>) {
+		match self {
+			Self::Star(h) => h.handle_update(drag_start, document, input, responses),
+			Self::Polygon(h) => h.handle_update(drag_start, document, input, responses),
+			Self::None => {}
+		}
+	}
+
+	/// Cleans up any state used by the gizmo handler.
+	pub fn cleanup(&mut self) {
+		match self {
+			Self::Star(h) => h.cleanup(),
+			Self::Polygon(h) => h.cleanup(),
+			Self::None => {}
+		}
+	}
+
+	/// Draws overlays like control points or outlines for the shape handled by this gizmo.
+	pub fn overlays(
+		&self,
+		document: &DocumentMessageHandler,
+		layer: Option<LayerNodeIdentifier>,
+		input: &InputPreprocessorMessageHandler,
+		shape_editor: &mut &mut ShapeState,
+		mouse_position: DVec2,
+		overlay_context: &mut OverlayContext,
+	) {
+		match self {
+			Self::Star(h) => h.overlays(document, layer, input, shape_editor, mouse_position, overlay_context),
+			Self::Polygon(h) => h.overlays(document, layer, input, shape_editor, mouse_position, overlay_context),
+			Self::None => {}
+		}
+	}
+
+	/// Draws live-updating overlays during drag interactions for the shape handled by this gizmo.
+	pub fn dragging_overlays(
+		&self,
+		document: &DocumentMessageHandler,
+		input: &InputPreprocessorMessageHandler,
+		shape_editor: &mut &mut ShapeState,
+		mouse_position: DVec2,
+		overlay_context: &mut OverlayContext,
+	) {
+		match self {
+			Self::Star(h) => h.dragging_overlays(document, input, shape_editor, mouse_position, overlay_context),
+			Self::Polygon(h) => h.dragging_overlays(document, input, shape_editor, mouse_position, overlay_context),
+			Self::None => {}
+		}
+	}
+}
+
+/// Central manager that coordinates shape gizmo handlers for interactive editing on the canvas.
+///
+/// The `GizmoManager` is responsible for detecting which shapes are selected, activating the appropriate
+/// shape-specific gizmo, and routing user interactions (hover, click, drag) to the correct handler.
+/// It allows editing multiple shapes of the same type or focusing on a single active shape when a gizmo is hovered.
+///
+/// ## Responsibilities:
+/// - Detect which selected layers support shape gizmos (e.g., stars, polygons)
+/// - Activate the correct handler and manage state between frames
+/// - Route click, hover, and drag events to the proper shape gizmo
+/// - Render overlays and dragging visuals
+#[derive(Clone, Debug, Default)]
+pub struct GizmoManager {
+	active_shape_handler: Option<ShapeGizmoHandlers>,
+	layers_handlers: Vec<(ShapeGizmoHandlers, Vec<LayerNodeIdentifier>)>,
+}
+
+impl GizmoManager {
+	/// Detects and returns a shape gizmo handler based on the layer type (e.g., star, polygon).
+	///
+	/// Returns `None` if the given layer does not represent a shape with a registered gizmo.
+	pub fn detect_shape_handler(layer: LayerNodeIdentifier, document: &DocumentMessageHandler) -> Option<ShapeGizmoHandlers> {
+		// Star
+		if graph_modification_utils::get_star_id(layer, &document.network_interface).is_some() {
+			return Some(ShapeGizmoHandlers::Star(StarGizmoHandler::default()));
+		}
+
+		// Polygon
+		if graph_modification_utils::get_polygon_id(layer, &document.network_interface).is_some() {
+			return Some(ShapeGizmoHandlers::Polygon(PolygonGizmoHandler::default()));
+		}
+
+		None
+	}
+
+	/// Returns `true` if a gizmo is currently active (hovered or being interacted with).
+	pub fn hovering_over_gizmo(&self) -> bool {
+		self.active_shape_handler.is_some()
+	}
+
+	/// Called every frame to check selected layers and update the active shape gizmo, if hovered.
+	///
+	/// Also groups all shape layers with the same kind of gizmo to support overlays for multi-shape editing.
+	pub fn handle_actions(&mut self, mouse_position: DVec2, document: &DocumentMessageHandler, responses: &mut VecDeque<Message>) {
+		let mut handlers_layer: Vec<(ShapeGizmoHandlers, Vec<LayerNodeIdentifier>)> = Vec::new();
+
+		for layer in document.network_interface.selected_nodes().selected_visible_and_unlocked_layers(&document.network_interface) {
+			if let Some(mut handler) = Self::detect_shape_handler(layer, document) {
+				handler.handle_state(layer, mouse_position, document, responses);
+				let is_hovered = handler.is_any_gizmo_hovered();
+
+				if is_hovered {
+					self.layers_handlers.clear();
+					self.active_shape_handler = Some(handler);
+					return;
+				}
+
+				// Try to group this handler with others of the same type
+				if let Some((_, layers)) = handlers_layer.iter_mut().find(|(existing_handler, _)| existing_handler.kind() == handler.kind()) {
+					layers.push(layer);
+				} else {
+					handlers_layer.push((handler, vec![layer]));
+				}
+			}
+		}
+
+		self.layers_handlers = handlers_layer;
+		self.active_shape_handler = None;
+	}
+
+	/// Handles click interactions if a gizmo is active. Returns `true` if a gizmo handled the click.
+	pub fn handle_click(&mut self) -> bool {
+		if let Some(handle) = &mut self.active_shape_handler {
+			handle.handle_click();
+			return true;
+		}
+		false
+	}
+
+	pub fn handle_cleanup(&mut self) {
+		if let Some(handle) = &mut self.active_shape_handler {
+			handle.cleanup();
+		}
+	}
+
+	/// Passes drag update data to the active gizmo to update shape parameters live.
+	pub fn handle_update(&mut self, drag_start: DVec2, document: &DocumentMessageHandler, input: &InputPreprocessorMessageHandler, responses: &mut VecDeque<Message>) {
+		if let Some(handle) = &mut self.active_shape_handler {
+			handle.handle_update(drag_start, document, input, responses);
+		}
+	}
+
+	/// Draws overlays for the currently active shape gizmo during a drag interaction.
+	pub fn dragging_overlays(
+		&self,
+		document: &DocumentMessageHandler,
+		input: &InputPreprocessorMessageHandler,
+		shape_editor: &mut &mut ShapeState,
+		mouse_position: DVec2,
+		overlay_context: &mut OverlayContext,
+	) {
+		if let Some(handle) = &self.active_shape_handler {
+			handle.dragging_overlays(document, input, shape_editor, mouse_position, overlay_context);
+		}
+	}
+
+	/// Draws overlays for either the active gizmo (if hovered) or all grouped selected gizmos.
+	///
+	/// If no single gizmo is active, it renders overlays for all grouped layers with associated handlers.
+	pub fn overlays(
+		&self,
+		document: &DocumentMessageHandler,
+		input: &InputPreprocessorMessageHandler,
+		shape_editor: &mut &mut ShapeState,
+		mouse_position: DVec2,
+		overlay_context: &mut OverlayContext,
+	) {
+		if let Some(handler) = &self.active_shape_handler {
+			handler.overlays(document, None, input, shape_editor, mouse_position, overlay_context);
+			return;
+		}
+
+		for (handler, selected_layers) in &self.layers_handlers {
+			for layer in selected_layers {
+				handler.overlays(document, Some(*layer), input, shape_editor, mouse_position, overlay_context);
+			}
+		}
+	}
+}

editor/src/messages/tool/common_functionality/gizmos/mod.rs

@@ -0,0 +1,2 @@
+pub mod gizmo_manager;
+pub mod shape_gizmos;

editor/src/messages/tool/common_functionality/gizmos/shape_gizmos/mod.rs

@@ -0,0 +1,2 @@
+pub mod number_of_points_dial;
+pub mod point_radius_handle;