remove "primitivetype" property
This is no longer a part of mesh3d:
https://github.com/rforge/rgl/commit/87bcf7445cc7d7a28df7076cbf314128c6b29f07#diff-fb1a2ca62de6cfcab71eef95a8103b38
you're expected to look only for it or ib arrays for the type/s of primitives available (mesh3d can have both, and there might be other types but I'm not sure).
readobj already got there:
https://github.com/jefferis/readobj/blob/99e38c3e04d3756bc435e6806f5056675b40f53e/tests/testthat/test-loadobj.R#L16-L29
Also need to add meshColor
threed still has primitivetype: https://github.com/coolbutuseless/threed/blob/8a178036e090bb87c3aebbde01d3b0089e31d76c/R/mesh3d-conversion.R