feat: some moving around

app/src/lib/graph-interface/edges/Edge.svelte

@@ -0,0 +1,112 @@
+<script context="module" lang="ts">
+  const color = new Color(0x202020);
+  color.convertLinearToSRGB();
+
+  const color2 = color.clone();
+  color2.convertSRGBToLinear();
+
+  const circleMaterial = new MeshBasicMaterial({
+    color,
+    toneMapped: false,
+  });
+
+  const lineCache = new Map<number, BufferGeometry>();
+
+  const curve = new CubicBezierCurve(
+    new Vector2(0, 0),
+    new Vector2(0, 0),
+    new Vector2(0, 0),
+    new Vector2(0, 0),
+  );
+</script>
+
+<script lang="ts">
+  import { T } from "@threlte/core";
+  import { MeshLineMaterial } from "@threlte/extras";
+  import { BufferGeometry, MeshBasicMaterial, Vector3 } from "three";
+  import { Color } from "three/src/math/Color.js";
+  import { CubicBezierCurve } from "three/src/extras/curves/CubicBezierCurve.js";
+  import { Vector2 } from "three/src/math/Vector2.js";
+  import { createEdgeGeometry } from "./createEdgeGeometry.js";
+
+  export let from: { x: number; y: number };
+  export let to: { x: number; y: number };
+
+  let samples = 5;
+
+  let geometry: BufferGeometry;
+
+  let lastId: number | null = null;
+
+  const primeA = 31;
+  const primeB = 37;
+
+  export const update = function () {
+    const new_x = to.x - from.x;
+    const new_y = to.y - from.y;
+    const curveId = new_x * primeA + new_y * primeB;
+    if (lastId === curveId) {
+      return;
+    }
+
+    const mid = new Vector2(new_x / 2, new_y / 2);
+
+    if (lineCache.has(curveId)) {
+      geometry = lineCache.get(curveId)!;
+      return;
+    }
+
+    const length = Math.floor(
+      Math.sqrt(Math.pow(new_x, 2) + Math.pow(new_y, 2)) / 4,
+    );
+    samples = Math.min(Math.max(10, length), 60);
+
+    curve.v0.set(0, 0);
+    curve.v1.set(mid.x, 0);
+    curve.v2.set(mid.x, new_y);
+    curve.v3.set(new_x, new_y);
+
+    const points = curve
+      .getPoints(samples)
+      .map((p) => new Vector3(p.x, 0, p.y))
+      .flat();
+
+    geometry = createEdgeGeometry(points);
+    lineCache.set(curveId, geometry);
+  };
+
+  $: if (from || to) {
+    update();
+  }
+</script>
+
+<T.Mesh
+  position.x={from.x}
+  position.z={from.y}
+  position.y={0.8}
+  rotation.x={-Math.PI / 2}
+  material={circleMaterial}
+>
+  <T.CircleGeometry args={[0.3, 16]} />
+</T.Mesh>
+
+<T.Mesh
+  position.x={to.x}
+  position.z={to.y}
+  position.y={0.8}
+  rotation.x={-Math.PI / 2}
+  material={circleMaterial}
+>
+  <T.CircleGeometry args={[0.3, 16]} />
+</T.Mesh>
+
+{#if geometry}
+  <T.Mesh position.x={from.x} position.z={from.y} position.y={0.1} {geometry}>
+    <MeshLineMaterial
+      width={4}
+      attenuate={false}
+      color={color2}
+      toneMapped={false}
+    />
+  </T.Mesh>
+{/if}