Polyline with arrow material is blurry

[hpinkos]

Reported on the forum: https://groups.google.com/forum/?hl=en#!topic/cesium-dev/sFOMs4XMJQk

It's particularly noticeable when the polyline has a large width:

var viewer = new Cesium.Viewer('cesiumContainer');

var purpleArrow = viewer.entities.add({
    name : 'Purple straight arrow at height',
    polyline : {
        positions : Cesium.Cartesian3.fromDegreesArrayHeights([-75, 43, 500000,
                                                               -125, 43, 500000]),
        width : 100,
        arcType : Cesium.ArcType.NONE,
        material : new Cesium.PolylineArrowMaterialProperty(Cesium.Color.PURPLE)
    }
});

[mramato]

This also has major issues at horoizon views. Look at it from the front and you'll see crazy zig-zagging and jumping around the atmosphere overlap.

[hpinkos]

BONUS: It'd be nice of the width parameter was used for the width of the polyline, not the width of the arrow head. And the arrow head should maintain a nice proportion. It doesn't look good all stretched out like this for a polyline with a large width.

Requested here: https://groups.google.com/forum/?hl=en#!topic/cesium-dev/9rOaI3JGTAM

[klingerj]

Came across the issue that @mramato described by chance today, @emackey thought it was worth uploading a screenshot demonstrating the issue:

and here it is at a higher width:

[mccoy1]

This is an old issue, any traction on this?

[mramato]

@mccoy1 Good news/bad news.

Good: The artifacts/twistyness/jumping are all fixed by #8706 and #8727 which are in master now and will go out with the May 1st release. (Thanks again @kring!)

Bad: The blurriness on wide lines is still a problem for the arrow material.

@emackey Any idea on the blurriness? Since it's specific to the arrow material I'm assuming it's something specific to its shader?

[emackey]

Ah nerd-sniping me on this one eh? Back at ya: #8791 😄