DriftEngineMaths · function
raySphere
The nearest positive distance along a ray to a sphere's surface, or -1.
Explained in Coordinates and units.
function raySphere(origin: ArrayLike<number>, direction: ArrayLike<number>, centre: ArrayLike<number>, radius: number): numberimport { raySphere } from '@driftengine/core';Parameters
| Parameter | Type | Description |
|---|---|---|
origin | ArrayLike<number> | |
direction | ArrayLike<number> | |
centre | ArrayLike<number> | |
radius | number |
In depth
An origin inside the sphere reports the far root rather than a miss, which is the
same choice rayAabb makes for the same reason: a camera that has got inside something
pickable is still looking at it, and reporting a miss makes the object impossible to
click from close up.
direction must be unit length, which is what lets the quadratic drop its leading
coefficient.