feat: some moving around

app/src/lib/graph-interface/edges/createEdgeGeometry.ts

@@ -0,0 +1,100 @@
+import { BufferGeometry, Vector3, BufferAttribute } from 'three'
+import { setXY, setXYZ, setXYZW, setXYZXYZ } from './utils.js'
+
+
+export function createEdgeGeometry(points: Vector3[]) {
+
+  let shape = 'none'
+  let shapeFunction = (p: number) => 1
+
+  // When the component first runs we create the buffer geometry and allocate the buffer attributes
+  let pointCount = points.length
+  let counters: number[] = []
+  let counterIndex = 0
+  let side: number[] = []
+  let widthArray: number[] = []
+  let doubleIndex = 0
+  let uvArray: number[] = []
+  let uvIndex = 0
+  let indices: number[] = []
+  let indicesIndex = 0
+
+  if (shape === 'taper') {
+    shapeFunction = (p: number) => 1 * Math.pow(4 * p * (1 - p), 1)
+  }
+
+  for (let j = 0; j < pointCount; j++) {
+    const c = j / points.length
+    counters[counterIndex + 0] = c
+    counters[counterIndex + 1] = c
+    counterIndex += 2
+
+    setXY(side, doubleIndex, 1, -1)
+    let width = shape === 'none' ? 1 : shapeFunction(j / (pointCount - 1))
+    setXY(widthArray, doubleIndex, width, width)
+    doubleIndex += 2
+
+    setXYZW(uvArray, uvIndex, j / (pointCount - 1), 0, j / (pointCount - 1), 1)
+    uvIndex += 4
+
+    if (j < pointCount - 1) {
+      const n = j * 2
+      setXYZ(indices, indicesIndex, n + 0, n + 1, n + 2)
+      setXYZ(indices, indicesIndex + 3, n + 2, n + 1, n + 3)
+      indicesIndex += 6
+    }
+  }
+
+  const geometry = new BufferGeometry()
+  // create these buffer attributes at the correct length but leave them empty for now
+  geometry.setAttribute('position', new BufferAttribute(new Float32Array(pointCount * 6), 3))
+  geometry.setAttribute('previous', new BufferAttribute(new Float32Array(pointCount * 6), 3))
+  geometry.setAttribute('next', new BufferAttribute(new Float32Array(pointCount * 6), 3))
+  // create and populate these buffer attributes
+  geometry.setAttribute('counters', new BufferAttribute(new Float32Array(counters), 1))
+  geometry.setAttribute('side', new BufferAttribute(new Float32Array(side), 1))
+  geometry.setAttribute('width', new BufferAttribute(new Float32Array(widthArray), 1))
+  geometry.setAttribute('uv', new BufferAttribute(new Float32Array(uvArray), 2))
+  geometry.setIndex(new BufferAttribute(new Uint16Array(indices), 1))
+
+
+
+  let positions: number[] = []
+  let previous: number[] = []
+  let next: number[] = []
+  let positionIndex = 0
+  let previousIndex = 0
+  let nextIndex = 0
+  setXYZXYZ(previous, previousIndex, points[0].x, points[0].y, points[0].z)
+  previousIndex += 6
+  for (let j = 0; j < pointCount; j++) {
+    const p = points[j]
+    setXYZXYZ(positions, positionIndex, p.x, p.y, p.z)
+    positionIndex += 6
+    if (j < pointCount - 1) {
+      setXYZXYZ(previous, previousIndex, p.x, p.y, p.z)
+      previousIndex += 6
+    }
+    if (j > 0 && j + 1 <= pointCount) {
+      setXYZXYZ(next, nextIndex, p.x, p.y, p.z)
+      nextIndex += 6
+    }
+  }
+  setXYZXYZ(
+    next,
+    nextIndex,
+    points[pointCount - 1].x,
+    points[pointCount - 1].y,
+    points[pointCount - 1].z
+  )
+  const positionAttribute = (geometry.getAttribute('position') as BufferAttribute).set(positions)
+  const previousAttribute = (geometry.getAttribute('previous') as BufferAttribute).set(previous)
+  const nextAttribute = (geometry.getAttribute('next') as BufferAttribute).set(next)
+  positionAttribute.needsUpdate = true
+  previousAttribute.needsUpdate = true
+  nextAttribute.needsUpdate = true
+  geometry.computeBoundingSphere()
+
+  return geometry;
+
+}