worldmap-viewer: initial public history

1 files changed, 45 insertions, 0 deletions

diff --git a/viewer/js/lines.js b/viewer/js/lines.js
new file mode 100644
index 0000000..f29fe1f
--- /dev/null
+++ b/viewer/js/lines.js
@@ -0,0 +1,45 @@
+// lines.js — named groups of 1-px line segments in a three.js scene
+import * as THREE from 'three';
+
+export class LineSet {
+  constructor(scene) {
+    this.scene = scene;
+    this.objects = new Map();
+  }
+
+  set(id, positions, color, origin = null) {   // origin: positions are relative to it (float precision near the ground)
+    this.remove(id);
+    if (!positions.length) return;
+    const geom = new THREE.BufferGeometry();
+    geom.setAttribute('position', new THREE.BufferAttribute(positions, 3));
+    const obj = new THREE.LineSegments(geom, new THREE.LineBasicMaterial({ color, transparent: true, opacity: 0.85,
+      depthTest: this.depthTest ?? true, clippingPlanes: this.clip ?? null }));
+    obj.scale.setScalar(this.scale ?? 1);
+    if (origin) obj.position.set(origin[0], origin[1], origin[2]);
+    this.objects.set(id, obj);
+    this.scene.add(obj);
+  }
+
+  setClip(planes) {   // shared THREE.Plane objects: callers move them, every line follows
+    this.clip = planes;
+    for (const o of this.objects.values()) o.material.clippingPlanes = planes;
+  }
+
+  setTransform(scale, depthTest) {   // globe: hug the ground when zoomed in and draw on top of tiles
+    this.scale = scale;
+    this.depthTest = depthTest;
+    for (const o of this.objects.values()) {
+      o.scale.setScalar(scale);
+      o.material.depthTest = depthTest;
+    }
+  }
+
+  remove(id) {
+    const obj = this.objects.get(id);
+    if (!obj) return;
+    this.scene.remove(obj);
+    obj.geometry.dispose();
+    obj.material.dispose();
+    this.objects.delete(id);
+  }
+}