I try to read the example .i3dm file in Sandcastle of 3d-tiles-transform branch, and have problems about the Specs\Data\Cesium3DTiles\Instanced\InstancedWithBatchTable\instancedWithBatchTable.i3dm
In this file, the BATCH_ID property is hard to interpret.
Firstly, the featureTableBinaryByteLength = 452, the BATCH_ID.byteOffset = 300; So I think the length of batch_id in binary should be 152 byte. Since the datatype of bathch_id is uint16 (2 byte), there are 76 batchid for 25 instances. So how many vertices in each instances have batch_id?
Secondly, I used nodejs buffer.readUint16LE() to read batch_id, the first 25 values are from 0 to 24. But from the 26th one, the values all became 0, and the last value is an extremely large one.
I can’t find any description about batch_id in featureTable specification. It will be really helpful to have someone point out my mistake.
Any help appreciated