Add phylotree layout

src/scripts/layout/cladogram.ts

+import { hierarchy, cluster } from "d3-hierarchy";
+import { RawPhyloTreeNode, PhyloTreeNode } from "../types";
+import { defaultSeparation } from "./phylotree";
+export default function () {
+  let dx = 1;
+  let dy = 1;
+  let nodeSize: boolean | null = null;
+  let separation = defaultSeparation;
+  function cladogram(data: RawPhyloTreeNode) {
+    // Apply the layout hierarchy.
+    cluster()
+      .separation(separation)
+      (hierarchy(data))
+    return data;
+  }
+
+  // PUBLIC
+  cladogram.nodeSize = function (size: [number, number]) {
+    nodeSize = true;
+    dx = +size[0];
+    dy = +size[1];
+    return cladogram;
+  };
+
+  cladogram.size = function (size: [number, number]) {
+    dx = +size[0];
+    dy = +size[1];
+    return cladogram;
+  }
+
+  cladogram.separation = function <T>(
+    separationCb: (a: d3.HierarchyNode<T>, b:d3.HierarchyNode<T>) => number
+  ) {
+    separation = separationCb;
+  }
+
+
+  return cladogram;
+
+}
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src/scripts/layout/phylotree.ts

+
+export function defaultSeparation<T>(
+  a: d3.HierarchyPointNode<T>, b: d3.HierarchyPointNode<T>
+): number {
+  return 1;
+  // return (a && b && a.parent === b.parent) ? 1 : 2;
+}
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