HERE 地图中的标签非常小

Question

根据 HERE Maps JS API platform.createDefaultLayers，通过更改 ppi 参数，将调整字体大小。但是，我无法在地图上看到任何差异。从下面的截图中可以看出，标签太小了。如何使标签在 7 英寸 1080p 显示器上可读？

var defaultLayers = platform.createDefaultLayers(512,  320 );
  
 //Step 2: initialize a map
 var map = new H.Map(document.getElementById('slide-map'),
    defaultLayers.vector.normal.map,{
    center: {lat:27.7279, lng:85.3284},
    zoom: 18,
    pixelRatio: 1
  });

Answer 1

carnav 方案和 normal.day.custom 只接受正常的 ppi。参见：https://developer.here.com/documentation/map-tile/dev_guide/topics/resource-base-basetile.html#resource-base-basetile__includes-query-parameters

Answer 2

这里有一些方法可以根据设备像素比调整图块大小。

var defaultLayers = platform.createDefaultLayers({
      tileSize: devicePixelRatio > 1 ? 512 : 256,
      ppi: devicePixelRatio > 1 ? 320 : 72
    });

    // Step 3: initialize the map
    var map = new H.Map(
      document.getElementById('map'),
      defaultLayers.normal.map,
      {
        center: { lat: 47.056, lng: 2.350 },
        zoom: 6,
        pixelRatio: Math.min(devicePixelRatio, 2)  // capping at 2 since some devices have a pixel ratio above 2 
      }
    );

更多详情请查看-

https://developer.here.com/documentation/map-tile/dev_guide/topics/resource-base-basetile.html#resource-base-basetile__includes-query-parameters

Answer 3

当我将 defaultLayers.vector.normal.map 更改为 defaultLayers.raster.normal.map 时，tileSize 和 ppi 参数开始影响标签大小。

var defaultLayers = platform.createDefaultLayers(512,  320 );
  
 //Step 2: initialize a map
 var map = new H.Map(document.getElementById('slide-map'),
    defaultLayers.raster.normal.map,{
    center: {lat:27.7279, lng:85.3284},
    zoom: 18,
    pixelRatio: 1
  });

HERE 地图中的标签非常小

Very small labels in HERE Maps

here-api