Model matrix not getting applied to tileset correctly

[lilleyse]

This bug goes back to at least 1.42.

The modelMatrix property seems to have some weird interaction with the ContextCapture tileset posted here. The tileset uses the CESIUM_RTC extension but is in local coordinates.

Default view at center of the Earth:

With model matrix applied

Debugging Sandcastle demo

The good thing is when upgrading the tileset with 3d-tiles-tools (links to the 2.0-tools branch) the tileset is correct. Also needs to be running on a branch that combines #7035 and #6805. Hopefully it is easy to track down.

Debugging Sandcastle demo

[lilleyse]

The reason for the bad positions in the second image is CESIUM_RTC applies its translation after the model matrix. Saw the same problem in here: #6755 (comment).

The summary here is CESIUM_RTC doesn't work well with model matrices that have rotation. Upgrading the tileset with 3d-tiles-tools, which changes CESIUM_RTC to RTC_CENTER, is the best fix.

[OmarShehata]

Same issue in this forum thread, retiling with Cesium ion fixes it.

[engineerhe]

I can not upgrade my model , the problem as above

[engineerhe]

The reason for the bad positions in the second image is CESIUM_RTC applies its translation after the model matrix. Saw the same problem in here: #6755 (comment).

The summary here is CESIUM_RTC doesn't work well with model matrices that have rotation. Upgrading the tileset with 3d-tiles-tools, which changes CESIUM_RTC to RTC_CENTER, is the best fix.

I can not resolve it , the 3d-tiles-tools is not working properly

[OmarShehata]

@engineerhe just to narrow down the issue here, can you confirm if tiling your source data with Cesium ion produces a tileset that works as expected?

[engineerhe]

@OmarShehata,Thanks for your patient answer,I followed the steps below to solve the problem.
Firstly,i use obj23dtiles tool tiling my data and generate 3dtiles.
Secondly , i use 3d-tiles-tools to upgrade tileset ,but it always reports an error which Binary gLTF version is not 1.
so,i want to know besides upgrading the tileset or retiling the tileset ,is there any other way to solve the problom?

[engineerhe]

@OmarShehata,i have solved it . Thanks！

[OmarShehata]

@engineerhe can you describe what the solution was?

[engineerhe]

Sorry, I didn't see the message until now.The solution is very sample , you just switch obj23dtiles tool into branch 2.0.

[lvfeijian]

Sorry, I didn't see the message until now.The solution is very sample , you just switch obj23dtiles tool into branch 2.0.
obj23dtiles the address https://github.com/engineerhe/objTo3d-tiles??