2*pi appears to me to be a Constant block.
The triangle at the S port of the Ideal Angular Velocity Source is part of the way the block is drawn; https://www.mathworks.com/help/simscape/ref/idealangularvelocitysource.html and is not a block itself.
The green "furry" part feeding into the C port of the Ideal Angular Velocity Source is a Mechanical Rotation Reference block; https://www.mathworks.com/help/simscape/ref/mechanicalrotationalreference.html
I am not certain about the f(x)=0 . I have seen it before at some point, but cannot find information about it at the moment.
I was not able to figure out the black filled triangle immediately beside the pen triangle.
