Files
vue-flow/examples/vite/src/FloatingEdges/floating-edge-utils.ts
2022-06-03 19:32:46 +02:00

106 lines
3.3 KiB
TypeScript

import type { Edge, GraphNode, XYPosition } from '../../packages/vue-flow'
import { MarkerType, Position } from '../../packages/vue-flow'
// this helper function returns the intersection point
// of the line between the center of the intersectionNode and the target node
function getNodeIntersection(intersectionNode: GraphNode, targetNode: GraphNode): XYPosition {
// https://math.stackexchange.com/questions/1724792/an-algorithm-for-finding-the-intersection-point-between-a-center-of-vision-and-a
const {
dimensions: { width: intersectionNodeWidth, height: intersectionNodeHeight },
position: intersectionNodePosition,
} = intersectionNode
const targetPosition = targetNode.position
const w = intersectionNodeWidth / 2
const h = intersectionNodeHeight / 2
const x2 = intersectionNodePosition.x + w
const y2 = intersectionNodePosition.y + h
const x1 = targetPosition.x + w
const y1 = targetPosition.y + h
const xx1 = (x1 - x2) / (2 * w) - (y1 - y2) / (2 * h)
const yy1 = (x1 - x2) / (2 * w) + (y1 - y2) / (2 * h)
const a = 1 / (Math.abs(xx1) + Math.abs(yy1))
const xx3 = a * xx1
const yy3 = a * yy1
const x = w * (xx3 + yy3) + x2
const y = h * (-xx3 + yy3) + y2
return { x, y }
}
// returns the position (top,right,bottom or right) passed node compared to the intersection point
function getEdgePosition(node: GraphNode, intersectionPoint: XYPosition) {
const n = { ...node.position, ...node.dimensions }
const nx = Math.round(n.x)
const ny = Math.round(n.y)
const px = Math.round(intersectionPoint.x)
const py = Math.round(intersectionPoint.y)
if (px <= nx + 1) {
return Position.Left
}
if (px >= nx + n.width - 1) {
return Position.Right
}
if (py <= ny + 1) {
return Position.Top
}
if (py >= n.y + n.height - 1) {
return Position.Bottom
}
return Position.Top
}
// returns the parameters (sx, sy, tx, ty, sourcePos, targetPos) you need to create an edge
export function getEdgeParams(source: GraphNode, target: GraphNode) {
const sourceIntersectionPoint = getNodeIntersection(source, target)
const targetIntersectionPoint = getNodeIntersection(target, source)
const sourcePos = getEdgePosition(source, sourceIntersectionPoint)
const targetPos = getEdgePosition(target, targetIntersectionPoint)
return {
sx: sourceIntersectionPoint.x,
sy: sourceIntersectionPoint.y,
tx: targetIntersectionPoint.x,
ty: targetIntersectionPoint.y,
sourcePos,
targetPos,
}
}
export function createElements() {
const win = typeof window !== 'undefined' ? window : ({} as any)
const elements = []
const center = { x: win.innerWidth / 2, y: win.innerHeight / 2 }
elements.push({ id: 'target', label: 'Target', position: center })
for (let i = 0; i < 8; i++) {
const degrees = i * (360 / 8)
const radians = degrees * (Math.PI / 180)
const x = 250 * Math.cos(radians) + center.x
const y = 250 * Math.sin(radians) + center.y
elements.push({ id: `${i}`, label: 'Source', position: { x, y } })
elements.push({
id: `edge-${i}`,
target: 'target',
source: `${i}`,
type: 'floating',
markerEnd: MarkerType.Arrow,
markerStart: {
id: 'markerstart',
type: MarkerType.Arrow,
orient: 'auto-start-reverse',
},
} as Edge)
}
return elements
}