Why this code use target key points to predict source key points?

[hailong23-jin]

I found that this code use the target key points to prediction source keys points as shown in the code: https://github.com/SunghwanHong/Cost-Aggregation-transformers/blob/main/utils_training/evaluation.py#L25.

However, the other papers leverage the source key points to predict target points.

https://github.com/juhongm999/chm/blob/main/common/evaluation.py#L13

https://github.com/wintersun661/MMNet/blob/main/evaluation_tools/evaluation.py#L10

https://github.com/wookiekim/transformatcher/blob/main/logger.py#L179

Why not just follow the most common settings?