How do I get texture coordinates of type "wcs_channel"

When using OpenNURBS to parse 3DM files, I learned that the texture coordinates of type ON_Texture::MAPPING_CHANNEL::wcs_channel are based on the world coordinate system. However, I don’t know how to retrieve these texture coordinates. I have tried using ON_Mesh::m_S and ON_Mesh::m_T, but they do not give me the correct texture coordinates. What method should I use to obtain the UV values?
Dingtalk_20231204175802

I think I know how to get the texture coordinates in the wcs_channel mode now. In this mode, the texture coordinates are simply the values of the vertex coordinates. However, when I retrieve the values using ON_Texture::m_uvw, I get the Mapping values of the Channel mode. How can I get the Mapping values in the WCS/OCS and WCS/OCS (box style) modes?

@johnc - can you help?

Thank you for your reply. After my research, I found that the texture coordinate transformation matrices in the Mapping Channel pattern are interconnected and mutually influenced with the WCS/OCS and WCS/OCS (box style) patterns. In other words, “m_uvw” represents the transformation matrix for any of these patterns, depending on which pattern you are using. Now, I can obtain the texture coordinate transformation matrices for WCS/OCS and WCS/OCS (box style) patterns from the values of “m_uvw” . Additionally, my program can now display the correct texture.
If you have anything to add, please let me know. Thank you!