These "weird" names are produced by the compiler and are called Name Mangling or Name Decoration. These names are shown by radare2 but are not produced or generated by it.
To quote from MSDN:
Functions, data, and objects in C and C++ programs are represented
internally by their decorated names. A decorated name is an encoded
string created by the compiler during compilation of an object, data,
or function definition. It records calling conventions, types,
function parameters and other information together with the name. This
name decoration, also known as name mangling, helps the linker find
the correct functions and objects when linking an executable.
The Wikipedia article about Name Mangling has some great examples of Name Mangling of C++ produced by GCC. I suggest you read it thoroughly to understand the subject better. It explains how mangled names are produced and describes the structure of it.
radare2, just as many different Disassemblers, knows to demangle the different names. There are several configuration variables that handle Name Mangling:
asm.demangle: Show demangled symbols in disasm
bin.demangle: Import demangled symbols from RBin
bin.demanglecmd: run xcrun swift-demangle and similar if available (SLOW)
bin.lang: Language for bin.demangle
So if you want radare2 to show you the demangled names on the assembly, use
e asm.demangle = true. Make sure to tell radare2 to load the demangled symbols. You can do this by setting
e bin.demangle to true. You might need to load the binary again - use
oo for this.
If you just want to demangle a specific name, you can use
iD <lang> <name> which will demangle a symbol name for a specific language. Just use it like this:
iD cxx <mangled name> for C++ Name Mangling.