Skip to main content
Solved

Are Cesium 3DTiles already DRACO compressed?

  • July 30, 2024
  • 1 reply
  • 172 views
oliverwesp
Participant
Forum|alt.badge.img+3

Hi,

I currently work with the Cesium 3DTiles writer and stumpled upon some requests asking for support for the DRACO compression.
I tried to do apply the compression afterwards using ‘3d-tiles-tools’ with no luck. So I took a deeper look on the b3dm Files using ‘3d-tiles-tools analyze’ and it looks to me like it’s already DRACO compressed. 

‘3d-tiles-tools analyze’ gives me:

{
  "asset": {
    "generator": "FME 2022.2.5.0",
    "version": "2.0"
  }, 
[...]
"meshes": [
    {
      "primitives": [
        {
          "attributes": {
            "_BATCHID": 4,
            "NORMAL": 2,
            "POSITION": 1,
            "COLOR_0": 3
          },
          "indices": 0,
          "material": 0,
          "mode": 4,
          "extensions": {
            "KHR_draco_mesh_compression": {
              "bufferView": 0,
              "attributes": {
                "_BATCHID": 3,
                "POSITION": 0,
                "NORMAL": 1,
                "COLOR_0": 2
              }
            }
          }
        }
      ]
    }
  ],
  [...]
  "scene": 0,
  "extensionsUsed": [
    "CESIUM_RTC",
    "KHR_draco_mesh_compression"
  ],
  "extensionsRequired": [
    "CESIUM_RTC",
    "KHR_draco_mesh_compression"
  ],
[...]
}

Can somebody confirm that the Cesium 3D Tiles writer is already doing DRACO compression? Or am I missing something?

best regards,
Oliver

Best answer by virtualcitymatt

Yes, the extension present suggests draco compression is already in use.

One thing which you can do is to use 3d-tiles-tools to decompress and then recompress. You might find that the compression is better. I’ve seen this in the past. 

Draco compression was added I think with FME 2021 or FME 2022.

This post is closed to further activity.
It may be an old question, an answered question, an implemented idea, or a notification-only post.
Please check post dates before relying on any information in a question or answer.
For follow-up or related questions, please post a new question or idea.
If there is a genuine update to be made, please contact us and request that the post is reopened.

1 reply

virtualcitymatt
Celebrity
Forum|alt.badge.img+47

Yes, the extension present suggests draco compression is already in use.

One thing which you can do is to use 3d-tiles-tools to decompress and then recompress. You might find that the compression is better. I’ve seen this in the past. 

Draco compression was added I think with FME 2021 or FME 2022.

oliverwesp

Community Stats

32,154
Posts
122,043
Replies
39,812
Members

Latest FME

Terms & ConditionsCookie settingsAccessibility statement
A product of
Safe Software respectfully acknowledges that we live, learn and work on the traditional and unceded territories of the Kwantlen, Katzie, and Semiahmoo First Nations.