[bug] rgl:::triangulateSimple fails with 3 Points

[discoleo]

rgl:::triangulateSimple fails with 3 Points

Note: polygon3d calls rgl:::triangulateSimple;

The variable good is defined only inside the while-loop:
while ((m <- length(verts)) > 3) {...}

But this while-loop is skipped for 3 points, generating an error.