Google map: How to rotate `groundoverlay` need trick

问题

I'm making map project for use like adding shapes and location on map and save it.

but i'm getting problem with groundoverlay.

i know there is no property exist for rotation in google map document. but i need a way/trick to rotate groundoverlay image, by any other way.

here code

var srcImage = "http://demo/image/uploads/demo.jpg";
var bounds = {
    north: 44.599,
    south: 44.490,
    east: -78.443,
    west: -78.649
}
var overlay = new google.maps.GroundOverlay(srcImage ,bounds);
overlay.setMap(map);

i am using slider for rotate overlay.

$("#overlayslider").slider().on('slide',function(e){
     var angle = e.newVal;
     // i want rotate overlay by angle/degree as per slider
})

I have tried with projection but no success.

Any posible way will be appreciate.

Any help will be useful, thank you.

回答1:

You can achieve this by using a custom overlay: https://developers.google.com/maps/documentation/javascript/examples/overlay-simple.

Add an event listener to the overlay slider in USGSOverlay.prototype.onAdd and then set the rotation of the div on input.

document.getElementById('overlayslider').addEventListener('input', function() {
    div.style.transform = 'rotate(' + this.value + 'deg)';
});

And here is the modified custom overlay example: https://jsfiddle.net/b0tLd46u/4/. You can set the rotation of the overlay by the range slider above the map.

回答2:

Here is my solution mostly inspirered from This Answer

rotated-overlay.ts

export class CustomOverlay extends google.maps.OverlayView {
  private div;

  constructor(
    private bounds: google.maps.LatLngBounds,
    private image: string,
    private rotation: number
  ) {
    super();

    // Define a property to hold the image's div. We'll
    // actually create this div upon receipt of the onAdd()
    // method so we'll leave it null for now.
    this.div = null;
  }

  /**
   * onAdd is called when the map's panes are ready and the overlay has been
   * added to the map.
   */
  onAdd() {
    const div = document.createElement('div');
    div.style.borderStyle = 'none';
    div.style.borderWidth = '0px';
    div.style.position = 'absolute';

    // Create the img element and attach it to the div.
    const img = document.createElement('img');
    img.src = this.image;
    img.style.width = '100%';
    img.style.height = '100%';
    img.style.position = 'absolute';
    div.appendChild(img);

    this.div = div;

    // Add the element to the "overlayLayer" pane.
    const panes = this.getPanes();
    panes.overlayLayer.appendChild(div);
  };

  draw() {

    // We use the south-west and north-east
    // coordinates of the overlay to peg it to the correct position and size.
    // To do this, we need to retrieve the projection from the overlay.
    const overlayProjection = this.getProjection();

    // Retrieve the south-west and north-east coordinates of this overlay
    // in LatLngs and convert them to pixel coordinates.
    // We'll use these coordinates to resize the div.
    const sw = overlayProjection.fromLatLngToDivPixel(this.bounds.getSouthWest());
    const ne = overlayProjection.fromLatLngToDivPixel(this.bounds.getNorthEast());

    // Resize the image's div to fit the indicated dimensions.
    const div = this.div;
    div.style.left = sw.x + 'px';
    div.style.top = ne.y + 'px';
    div.style.width = (ne.x - sw.x) + 'px';
    div.style.height = (sw.y - ne.y) + 'px';
    div.style.transform = 'rotate(' + this.rotation + 'deg)';
  };

  // The onRemove() method will be called automatically from the API if
  // we ever set the overlay's map property to 'null'.
  onRemove() {
    this.div.parentNode.removeChild(this.div);
    this.div = null;
  };
};

map-component.ts

public addOverlay(imageUrl: string, rotation: number, bounds: google.maps.LatLngBounds, map: google.maps.Map){
  let overlay = new CustomOverlay(
    bounds,
    imageUrl,
    rotation,
    
  );
  overlay.setMap(map);
}

来源：https://stackoverflow.com/questions/52948764/google-map-how-to-rotate-groundoverlay-need-trick