setLayerZoomRange causing rasters to be re-requested

[nreese]

Whenever setLayerZoomRange is called with new min/max values on a layer containing raster tiles, all tiles are requested. Is this expected behavior? I am using mapbox-gl version 0.45.0 in Chrome 71.0.3578.98.

Below is the code used to create the layer.

    mbMap.addSource(sourceId, {
      type: 'raster',
      tiles: [url],
      tileSize: 256,
      scheme: 'xyz',
    });

    mbMap.addLayer({
      id: mbLayerId,
      type: 'raster',
      source: sourceId,
      minzoom: 0,
      maxzoom: 22,
    });

Then if mbMap.setLayerZoomRange(mbLayerId, 0, 15); is called, all tiles are re-fetched. Why are the tiles re-fetched? The map is at zoom level 3 so the change should have no effect on the current tiles.

[mourner]

@nreese

• Did you make sure the behavior is the same on the latest version, v0.52.0 or v0.53.0-beta.1?
• Can you set up a minimal reproducible test case to demonstrate this (e.g. with JSFiddle)?

[nreese]

@mourner The problem exists in v0.52.0. Here is a js-fiddle that demonstrates the problem https://jsfiddle.net/reesenathan/pwb6nz74/. Adjust the slider in the top left corner and notice that when you release the slider and setLayerZoomRange is triggered, the tiles flicker because they are getting re-fetched.

[peterqliu]

Looks like killing this line removes the flicker, while preserving the method functionality both when inside the new zoom range or not:

mapbox-gl-js/src/style/style.js

Line 735 in ead961f

this._updateLayer(layer);

any downsides to not reloading the layer source after calling setLayerZoomRange, and not pausing the SourceCache, that I'm not seeing?