Fix erratic glTF progress values

[bghgary]

See https://forum.babylonjs.com/t/sceneloader-load-progress-rollback/50805.

The main problem is that we were removing the requests from the array which is used for calculating the total, making the total drop as requests complete. But even if we stop removing the requests, it won't always work properly if there are requests with lengthComputable = false. To solve this, we can force lengthComputable to true and set total to loaded when the request is complete to make sure the progress is counted.

[bjsplat]

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[bjsplat]

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[Jeggery]

we can force lengthComputable to true and set total to loaded when the request is complete to make sure the progress is counted.

Will it still take effect if gzipped is used？

[bjsplat]

WebGL2 visualization test reporter:

https://babylonsnapshots.z22.web.core.windows.net/refs/pull/15136/merge/testResults/webgl2playwright/index.html

[bjsplat]

Visualization tests for WebGPU (Experimental)

https://babylonsnapshots.z22.web.core.windows.net/refs/pull/15136/merge/testResults/webgpuplaywright/index.html

[bghgary]

we can force lengthComputable to true and set total to loaded when the request is complete to make sure the progress is counted.

Will it still take effect if gzipped is used？

I'm not sure what you mean by "take effect". If a file is gzipped on the server, the lengthComputable will likely be false. The total property will not be available. With the new code, all I'm doing is pretending that lengthComputable is true and that the length is the amount of data loaded when the request is complete to aid in computing the total of all the requests. This means that the total progress won't be available while loading a request where lengthComputable is false, but it will be available as soon as that request completes.

[Jeggery]

we can force lengthComputable to true and set total to loaded when the request is complete to make sure the progress is counted.

Will it still take effect if gzipped is used？

I'm not sure what you mean by "take effect". If a file is gzipped on the server, the lengthComputable will likely be false. The total property will not be available. With the new code, all I'm doing is pretending that lengthComputable is true and that the length is the amount of data loaded when the request is complete to aid in computing the total of all the requests. This means that the total progress won't be available while loading a request where lengthComputable is false, but it will be available as soon as that request completes.

Thank you. I get it