Polygons with transparent fill not drawn properly when tilting camera

[Schumi09]

Hi there,

polygons that have a transparent fill are not drawn properly when tilting the camera.

Platform:
Android 4.4.2 (Sony Xperia P)
Mapbox SDK version:
4.0.0, 4.1.0-SNAPSHOT

Steps to trigger behavior

1. Used demo app
2. Set new Cameraposition with tilt

CameraPosition cameraPosition = new CameraPosition.Builder() .target(new LatLng(51.963493, 7.617811)) .zoom(15) .tilt(30) .build(); mMapboxMap.moveCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));

1. Set up a polygon with transparent fill, e.g.:
   • mapboxMap.addPolygon(new PolygonOptions().add(new LatLng(51.963493, 7.617811)).add(new LatLng(51.964233, 7.620922)).add(new LatLng(51.965575, 7.617070)).fillColor(Color.parseColor("#00000000")) .strokeColor(Color.parseColor("#ff000000")));

Expected behavior

Properly drawn polygons as it is without tilted camera, before 4.0.0 it worked fine I think. I did not test it again, but I'm pretty sure.

Actual behavior

[ansis]

You can work around this issue by using adding a line instead of a polygon.

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Polygon outlines are drawn with gl.LINES instead of gl.TRIANGLES. The interpolation between vertices does not work the way we expected it to. The -gl-js version of this issue: mapbox/mapbox-gl-js#1047

Switching from gl.LINES to gl.TRIANGLES rendering would fix this mapbox/mapbox-gl-js#2080

[Schumi09]

Thanks for your reply. I already used the work-around ;)