I want to add water material to 3dtiles,But it's not feasibl ?

1. A concise explanation of the problem you're experiencing.

I want to add water material to 3dtiles,But it's not feasibl

2. A minimal code example. If you've found a bug, this helps us reproduce and repair it.

<script>
    var worldTerrain = Cesium.createWorldTerrain({
    requestWaterMask: true,
    requestVertexNormals: true
    });

    var viewer = new Cesium.Viewer('cesiumContainer', {
        terrainProvider: worldTerrain
    });

    var tileset = new Cesium.Cesium3DTileset({
        // url: ‘../../cesiumLab3dtiles/tileset.json’
         url: ‘http://localhost:8030/jinjiangData_3dtiles/tileset.json
    });

    var rectangle;

    tileset.readyPromise.then(function (tileset) {
          viewer.scene.primitives.add(tileset);
          var cartographic = Cesium.Cartographic.fromCartesian(tileset.boundingSphere.center);
          var surface = Cesium.Cartesian3.fromRadians(cartographic.longitude, cartographic.latitude, 0.0);
          var offset = Cesium.Cartesian3.fromRadians(cartographic.longitude, cartographic.latitude, 2.0);
          var translation = Cesium.Cartesian3.subtract(offset, surface, new Cesium.Cartesian3());
          tileset.modelMatrix = Cesium.Matrix4.fromTranslation(translation);
          viewer.zoomTo(tileset);
     }).otherwise(function(error) {
          console.log(error);
    });

function createPrimitives(scene) {
    rectangle = scene.primitives.add(new Cesium.GroundPrimitive({
        geometryInstances : new Cesium.GeometryInstance({
            geometry : new Cesium.PolygonGeometry({
                        polygonHierarchy : new Cesium.PolygonHierarchy(
                            Cesium.Cartesian3.fromDegreesArray( [112.16245241220456,22.26306407983288,112.16471144587265,22.26259584538233,112.16488040107146,22.26228180104898,112.16531192642532,22.26178655362098,112.16544305720755,22.262004561143097,112.16603461588957,22.26178718090819,112.1658874569952,22.26116962178944,112.16533945017264,22.26087417748411,112.16459935219373,22.26045067488058,112.16495228305284,22.2593670578392,112.16523853725937,22.258686629225963,112.1653752618481,22.25823538504829,112.16548886914792,22.25752735407626,112.16546121933982,22.256823942104013,112.16505423738998,22.256778880111597,112.16417391635653,22.247614376360875,112.16320701238239,22.246638177345762,112.16199919280076,22.245053935888226,112.16137620080613,22.24473864515594,112.1613019420769,22.243944197129153,112.16101776254885,22.243892101295508,112.16084462629308,22.243916071451103,112.16059341739938,22.243475029948865,112.16067364765551,22.24289679840787,112.16054491403355,22.2429510632919,112.15811464977565,22.24298244587892,112.15786729312002,22.24383679772685,112.1568784598097,22.243773277785877,112.1566834626063,22.244713117225032,112.155808823767,22.244762083245078,112.15586425189474,22.247551963170142,112.15389234965383,22.247539862570665,112.15376227800613,22.248530331906483,112.1527889697874,22.248504624994368,112.15282033195271,22.248573577120187,112.15268069785994,22.249511927660606,112.15210652740747,22.24987051996244,112.15190549594676,22.25295003520852,112.14757789914799,22.259234514524877,112.14268914304724,22.26158624919961,112.14261437418023,22.262897175306257,112.14341389120706,22.262980705405145,112.14441209969013,22.263089370414963,112.14456889198357,22.263907089781025,112.14632580645994,22.26377400428064,112.14769406779865,22.264659145302275,112.14981696909862,22.264604608772288,112.1495338397549,22.265618359592615,112.15119898151433,22.265573388663167,112.15108535107538,22.266652734866,112.1511315179183,22.266810737987683,112.15313976934056,22.266857680838562,112.15320521963447,22.2675975522776,112.15334554226354,22.267850672101144,112.15521364029752,22.267696045873688,112.16156586042219,22.261730762857038,112.1625290416967,22.263010804888378])
                          ),
                vertexFormat : Cesium.EllipsoidSurfaceAppearance.VERTEX_FORMAT
            })
        }),
        appearance : new Cesium.EllipsoidSurfaceAppearance({
            aboveGround : false
        }),
        classificationType : Cesium.ClassificationType.CESIUM_3D_TILE
    }));

}

function applyWaterMaterial(primitive, scene) {
    primitive.appearance.material = new Cesium.Material({
        fabric : {
            type : 'Water',
            uniforms : {
                normalMap: './WaterMaterialHelper/waterNormals.jpg',
                frequency: 10000.0,
                animationSpeed: 0.01,
                amplitude: 1.0
            }
        }
    });
}

var scene = viewer.scene;

createPrimitives(scene);
applyWaterMaterial(rectangle, scene);
</script>

Hint error : All GeometryInstances must have the same color attribute except via GroundPrimitives

3. Context. Why do you need to do this? We might know a better way to accomplish your goal.

I want to add water material to the 3dtiles model to simulate a surface effect.

4. The Cesium version you're using, your operating system and browser.

webkit 63.0

Is this the error you’re running into?

We plan on adding support for materials on 3D Tiles eventually, we’re tracking the issue here: https://github.com/AnalyticalGraphicsInc/cesium/issues/6636