Add transform-pointer-intent.ts for handling pointer down events

src/viewport-three/transform-pointer-intent.ts

@@ -0,0 +1,31 @@
+import type { TransformSessionState } from "../core/transform-session";
+import type { ViewportPanelId } from "./viewport-layout";
+
+export interface TransformPointerDownIntent {
+  commitActiveTransform: boolean;
+  allowGizmoInteraction: boolean;
+}
+
+export function resolveTransformPointerDownIntent(
+  transformSession: TransformSessionState,
+  panelId: ViewportPanelId
+): TransformPointerDownIntent {
+  if (transformSession.kind !== "active") {
+    return {
+      commitActiveTransform: false,
+      allowGizmoInteraction: true
+    };
+  }
+
+  if (transformSession.sourcePanelId !== panelId) {
+    return {
+      commitActiveTransform: false,
+      allowGizmoInteraction: false
+    };
+  }
+
+  return {
+    commitActiveTransform: true,
+    allowGizmoInteraction: false
+  };
+}