Function localFrameMatrix

localFrameMatrix(
    mainMatrix: ArrayLike<number>,
    origin: [number, number],
    options?: LocalFrameOptions,
): Float64Array
Returns the matrix that draws a local frame around origin on the map: x runs east, y north and z up from the origin, in metres, scaled as LocalFrameOptions sets.
- Call it in a custom layer's render, with options.defaultProjectionData.mainMatrix.
- It composes in double precision, so a street-scale scene doesn't jitter. Copy the result into a three.js camera's projectionMatrix, or into a Float32Array for a WebGL uniform.
- It works in the mercator projection. In the globe projection, the map's matrix takes other coordinates.
Parameters
- mainMatrix: ArrayLike<number>
  The map's defaultProjectionData.mainMatrix for this frame.
- origin: [number, number]
  The frame's origin, [longitude, latitude]. Its height is altitude.
- options: LocalFrameOptions = {}
Returns Float64Array
Example
```
render(gl, options) {
    const matrix = localFrameMatrix(options.defaultProjectionData.mainMatrix, [4.8897, 52.3731], {
        centerLatitude: map.mapLibreMap.getCenter().lat,
    });
    camera.projectionMatrix.fromArray(matrix);
    camera.projectionMatrixInverse.copy(camera.projectionMatrix).invert();
}
```