Render large amount of entities

Andrea_Vicari · April 15, 2017, 9:36pm

Hi,
I am trying to visualize ~19000 entities on the Cesium widget in order to render the buildings of a city.

I have the coordinates of the perimeter of every building in the city and I generate a different polygon and put it on the map.

The problem I am facing is the following: whenever the number of buildings to render is quite high (around 1000) Cesium starts lagging and after a while WebGL completely crashes and this error box from Cesium appears:

This is my code:

var buildings = new Cesium.CustomDataSource();
    $.ajax({
               url: SERVER_URL + "/building/max=46.061271,8.875321&min=45.940576,8.996019/", //COORDINATES TO GET BUILDINGS
               type: "GET",
               success: function (data) {
                   viewer.entities.suspendEvents();
                   for (var i = 0; i < data.length; i++) {
                       if (data[i]) {
                           var list = createList(data[i].ringGlobalCoords);
                           var height = (data[i].floors + 2) * 2;

                           viewer.entities.add({
                                             id: 'building_' + data[i].id,
                                             name: 'edificio',
                                             description: 'edificio desc',
                                             polygon: {
                                                 hierarchy: Cesium.Cartesian3.fromDegreesArray(list),
                                                 height: data[i].altitude,
                                                 extrudedHeight: (data[i].floors + 2) * 2,
                                                 material: Cesium.Color.WHITE,
                                                 outline: false,
                                                 closeTop: true,
                                                 closeBottom: false,
                                                 distanceDisplayCondition: new Cesium.DistanceDisplayCondition(0, 15000.0)
                                             }
                                         });
                       }
                   }
                   viewer.entities.resumeEvents();
               }
           });
    };

Do you have any idea how could I solve this problem or optimize the rendering of the buildings?

Thank you,
Andrea

Rachel_Hwang · April 18, 2017, 6:33pm

Hi Andrea,

For that much data, I would point you to 3d-tiles. See this forum discussion for details: https://groups.google.com/d/msg/cesium-dev/tCCooBxpZFU/7hxT_E4pGgAJ

3d-tiles should handle it!

Best,

Rachel

Andrea_Vicari · April 19, 2017, 3:46pm

Hi Rachel,

thank you for your answer. I have a question, though.

In order to render the entities, I have an array of coordinates that generates the perimeter of every 3d polygon and then I set the height.
As far as I understood from the 3D-tiles documentation, I would need a 3d tileset. Am I right?

Since I only have coordinates, how could I procede in this case?

I am looking forward to hearing from you.

Best,
Andrea

hannah · April 19, 2017, 7:15pm

Hello Andrea,

Yes, you would need to build a 3d tileset from the data you have. Right now, I don’t know of any tools to help you do this.

However, we have been working on a new website that will have services to help you process your data into 3D Tiles. Learn more information at https://www.cesium.com/

Best,

Hannah