Add support for resizing workspace panels (#443)

* Resize panels

* Removing move_selection test pending #444 resolved

* Bind event listners and cursor to the document

* Fix flex grow on document being reset when drawing

* Call onresize when the boundry is dragged

* Add min panel size

* Add explicit function return types

* Dispatch resize event

* Lock pointer instead of setting cursor on document

Co-authored-by: otdavies <oliver@psyfer.io>
Co-authored-by: Keavon Chambers <keavon@keavon.com>

editor/src/communication/dispatcher.rs

@@ -330,6 +330,7 @@ mod test {
 		assert_eq!(&layers_after_copy[4], rect_before_copy);
 		assert_eq!(&layers_after_copy[5], ellipse_before_copy);
 	}
+
 	#[test]
 	#[ignore] // TODO: Re-enable test, see issue #444 (https://github.com/GraphiteEditor/Graphite/pull/444)
 	/// - create rect, shape and ellipse

frontend/src/App.vue

@@ -241,7 +241,7 @@ declare module "@vue/runtime-core" {
 		editor: EditorState;
 		// This must be set to optional because there is a time in the lifecycle of the component where inputManager is undefined.
 		// That's because we initialize inputManager in `mounted()` rather than `data()` since the div hasn't been created yet.
-		inputManger?: InputManager;
+		inputManager?: InputManager;
 	}
 }
 

frontend/src/components/workspace/Workspace.vue

@@ -1,6 +1,6 @@
 <template>
 	<LayoutRow class="workspace-grid-subdivision">
-		<LayoutCol class="workspace-grid-subdivision" style="flex-grow: 1597">
+		<LayoutCol class="workspace-grid-subdivision">
 			<Panel
 				:panelType="'Document'"
 				:tabCloseButtons="true"
@@ -22,12 +22,12 @@
 				ref="documentsPanel"
 			/>
 		</LayoutCol>
-		<LayoutCol class="workspace-grid-resize-gutter"></LayoutCol>
+		<LayoutCol class="workspace-grid-resize-gutter" @pointerdown="resizePanel($event)"></LayoutCol>
-		<LayoutCol class="workspace-grid-subdivision" style="flex-grow: 319">
+		<LayoutCol class="workspace-grid-subdivision" style="flex-grow: 0.17">
 			<LayoutRow class="workspace-grid-subdivision" style="flex-grow: 402">
 				<Panel :panelType="'Properties'" :tabLabels="['Properties']" :tabActiveIndex="0" />
 			</LayoutRow>
-			<LayoutRow class="workspace-grid-resize-gutter"></LayoutRow>
+			<LayoutRow class="workspace-grid-resize-gutter" @pointerdown="resizePanel($event)"></LayoutRow>
 			<LayoutRow class="workspace-grid-subdivision" style="flex-grow: 590">
 				<Panel :panelType="'LayerTree'" :tabLabels="['Layer Tree']" :tabActiveIndex="0" />
 			</LayoutRow>
@@ -72,6 +72,8 @@ import LayoutRow from "@/components/layout/LayoutRow.vue";
 import DialogModal from "@/components/widgets/floating-menus/DialogModal.vue";
 import Panel from "@/components/workspace/Panel.vue";
 
+const MIN_PANEL_SIZE = 100;
+
 export default defineComponent({
 	inject: ["documents", "dialog", "editor"],
 	components: {
@@ -85,6 +87,54 @@ export default defineComponent({
 			return this.documents.state.activeDocumentIndex;
 		},
 	},
+	methods: {
+		resizePanel(event: PointerEvent) {
+			const gutter = event.target as HTMLElement;
+			const nextSibling = gutter.nextElementSibling as HTMLElement;
+			const previousSibling = gutter.previousElementSibling as HTMLElement;
+
+			// Are we resizing horizontally?
+			const horizontal = gutter.classList.contains("layout-col");
+
+			// Get the current size in px of the panels being resized
+			const nextSiblingSize = horizontal ? nextSibling.getBoundingClientRect().width : nextSibling.getBoundingClientRect().height;
+			const previousSiblingSize = horizontal ? previousSibling.getBoundingClientRect().width : previousSibling.getBoundingClientRect().height;
+
+			// Prevent cursor flicker as mouse temporarily leaves the gutter
+			gutter.setPointerCapture(event.pointerId);
+
+			const mouseStart = horizontal ? event.clientX : event.clientY;
+
+			function updatePosition(event: PointerEvent): void {
+				const mouseCurrent = horizontal ? event.clientX : event.clientY;
+				let mouseDelta = mouseStart - mouseCurrent;
+
+				mouseDelta = Math.max(nextSiblingSize + mouseDelta, MIN_PANEL_SIZE) - nextSiblingSize;
+				mouseDelta = previousSiblingSize - Math.max(previousSiblingSize - mouseDelta, MIN_PANEL_SIZE);
+
+				nextSibling.style.flexGrow = (nextSiblingSize + mouseDelta).toString();
+				previousSibling.style.flexGrow = (previousSiblingSize - mouseDelta).toString();
+
+				window.dispatchEvent(
+					new CustomEvent("resize", {
+						detail: {},
+					})
+				);
+			}
+
+			document.addEventListener("pointermove", updatePosition);
+
+			function cleanup(event: PointerEvent): void {
+				gutter.releasePointerCapture(event.pointerId);
+				document.removeEventListener("pointermove", updatePosition);
+				document.removeEventListener("pointerleave", cleanup);
+				document.removeEventListener("pointerup", cleanup);
+			}
+
+			document.addEventListener("pointerleave", cleanup);
+			document.addEventListener("pointerup", cleanup);
+		},
+	},
 	watch: {
 		activeDocumentIndex(newIndex: number) {
 			this.$nextTick(() => {