display artefacts with polygons

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jau...@gmail.com

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Sep 20, 2019, 10:09:55 AM9/20/19
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When zooming really closer to a polygon entity, it disappears partially which is not expected.
Then, when zoomed out, it appears again fully.
Here is a screenshot which display the artefact:

polygon_display_artefact.png


It would be the following indeed:

polygon_display_good.png


I do not understand why it disappears, the polygon would be fully rendered anytime.

Code which reproduce the issue.

var viewer = new Cesium.Viewer('cesiumContainer');
var bluePolygon = viewer.entities.add({
    polygon
: {
        hierarchy
: {
            positions
: Cesium.Cartesian3.fromDegreesArray([-99.0, 30.0,
                                                           
-85.0, 30.0,
                                                           
-85.0, 40.0,
                                                           
-99.0, 40.0]),
       
},
        material
: Cesium.Color.BLUE.withAlpha(0.5),
        height
: 0,
        outline
: true // height is required for outline to display
   
}
});
viewer
.zoomTo(viewer.entities);

Cesium 1.61
Windows 10
Chrome 76 / Firefox 69

Could be reproduced with height > 0, with or without outline, with "recent" releases of cesium, browsers, etc.
I just would like to know if this is a "famous issue" which cannot be solved and if I can do something to workaround it.

Thank you to give me help.

Omar Shehata

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Sep 23, 2019, 1:05:19 PM9/23/19
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This is a known issue with the logarithmic depth buffer. See: https://github.com/AnalyticalGraphicsInc/cesium/issues/6573

You can turn it off with:

viewer.scene.logarithmicDepthBuffer = false;

What kind of application are you working on?

jau...@gmail.com

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Sep 24, 2019, 5:31:34 AM9/24/19
to cesium-dev
Thanks Omar, it works perfectly !
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