Initial project import

node_modules/three-stdlib/math/MeshSurfaceSampler.cjs

@@ -0,0 +1,104 @@
+"use strict";
+Object.defineProperty(exports, Symbol.toStringTag, { value: "Module" });
+const THREE = require("three");
+const _face = /* @__PURE__ */ new THREE.Triangle();
+const _color = /* @__PURE__ */ new THREE.Vector3();
+class MeshSurfaceSampler {
+  constructor(mesh) {
+    let geometry = mesh.geometry;
+    if (geometry.index) {
+      console.warn("THREE.MeshSurfaceSampler: Converting geometry to non-indexed BufferGeometry.");
+      geometry = geometry.toNonIndexed();
+    }
+    this.geometry = geometry;
+    this.randomFunction = Math.random;
+    this.positionAttribute = this.geometry.getAttribute("position");
+    this.colorAttribute = this.geometry.getAttribute("color");
+    this.weightAttribute = null;
+    this.distribution = null;
+  }
+  setWeightAttribute(name) {
+    this.weightAttribute = name ? this.geometry.getAttribute(name) : null;
+    return this;
+  }
+  build() {
+    const positionAttribute = this.positionAttribute;
+    const weightAttribute = this.weightAttribute;
+    const faceWeights = new Float32Array(positionAttribute.count / 3);
+    for (let i = 0; i < positionAttribute.count; i += 3) {
+      let faceWeight = 1;
+      if (weightAttribute) {
+        faceWeight = weightAttribute.getX(i) + weightAttribute.getX(i + 1) + weightAttribute.getX(i + 2);
+      }
+      _face.a.fromBufferAttribute(positionAttribute, i);
+      _face.b.fromBufferAttribute(positionAttribute, i + 1);
+      _face.c.fromBufferAttribute(positionAttribute, i + 2);
+      faceWeight *= _face.getArea();
+      faceWeights[i / 3] = faceWeight;
+    }
+    this.distribution = new Float32Array(positionAttribute.count / 3);
+    let cumulativeTotal = 0;
+    for (let i = 0; i < faceWeights.length; i++) {
+      cumulativeTotal += faceWeights[i];
+      this.distribution[i] = cumulativeTotal;
+    }
+    return this;
+  }
+  setRandomGenerator(randomFunction) {
+    this.randomFunction = randomFunction;
+    return this;
+  }
+  sample(targetPosition, targetNormal, targetColor) {
+    const faceIndex = this.sampleFaceIndex();
+    return this.sampleFace(faceIndex, targetPosition, targetNormal, targetColor);
+  }
+  sampleFaceIndex() {
+    const cumulativeTotal = this.distribution[this.distribution.length - 1];
+    return this.binarySearch(this.randomFunction() * cumulativeTotal);
+  }
+  binarySearch(x) {
+    const dist = this.distribution;
+    let start = 0;
+    let end = dist.length - 1;
+    let index = -1;
+    while (start <= end) {
+      const mid = Math.ceil((start + end) / 2);
+      if (mid === 0 || dist[mid - 1] <= x && dist[mid] > x) {
+        index = mid;
+        break;
+      } else if (x < dist[mid]) {
+        end = mid - 1;
+      } else {
+        start = mid + 1;
+      }
+    }
+    return index;
+  }
+  sampleFace(faceIndex, targetPosition, targetNormal, targetColor) {
+    let u = this.randomFunction();
+    let v = this.randomFunction();
+    if (u + v > 1) {
+      u = 1 - u;
+      v = 1 - v;
+    }
+    _face.a.fromBufferAttribute(this.positionAttribute, faceIndex * 3);
+    _face.b.fromBufferAttribute(this.positionAttribute, faceIndex * 3 + 1);
+    _face.c.fromBufferAttribute(this.positionAttribute, faceIndex * 3 + 2);
+    targetPosition.set(0, 0, 0).addScaledVector(_face.a, u).addScaledVector(_face.b, v).addScaledVector(_face.c, 1 - (u + v));
+    if (targetNormal !== void 0) {
+      _face.getNormal(targetNormal);
+    }
+    if (targetColor !== void 0 && this.colorAttribute !== void 0) {
+      _face.a.fromBufferAttribute(this.colorAttribute, faceIndex * 3);
+      _face.b.fromBufferAttribute(this.colorAttribute, faceIndex * 3 + 1);
+      _face.c.fromBufferAttribute(this.colorAttribute, faceIndex * 3 + 2);
+      _color.set(0, 0, 0).addScaledVector(_face.a, u).addScaledVector(_face.b, v).addScaledVector(_face.c, 1 - (u + v));
+      targetColor.r = _color.x;
+      targetColor.g = _color.y;
+      targetColor.b = _color.z;
+    }
+    return this;
+  }
+}
+exports.MeshSurfaceSampler = MeshSurfaceSampler;
+//# sourceMappingURL=MeshSurfaceSampler.cjs.map