DriftEngineThe 2D layer · function
routeScrollWheel
Give a wheel to the innermost container under the pointer that can use it, then outwards.
Explained in Sprites and tilemaps.
function routeScrollWheel(root: UiNode, x: number, y: number, dx: number, dy: number): UiNode | nullimport { routeScrollWheel } from '@driftengine/ui2d';Parameters
| Parameter | Type | Description |
|---|---|---|
root | UiNode | |
x | number | |
y | number | |
dx | number | |
dy | number |
In depth
Innermost first is the order a person expects and the opposite of the order the tree makes convenient, so the chain is collected on the way down and walked back up. Returns the node that consumed it, or null when nothing did — which is a caller's signal to let the page have it.