Is sample : from key 
            0x025f37d20e5b18909361e0ead7ed17c69b417bee70746c9e9c2bcb1394d921d4ae 

resulting address is      
0xd09D3103CcABfb769eDc3e9B01500Ca7241D470A

I have using algorithm from keccak-tiny.c by David Leon Gil with change: padding with 0x01 instead 0x06: 7 bytes of message "testing" give me 5f16f4c7f149ac4f9510d9cf8cf384038ad348b3bcdc01915f95de12df9d1b02 as is in "Which cryptographic hash function does Ethereum use?"

In "Generating an address from a public key" is algorithm, but I have questions:
how exactly means getPublic,keyFromPublic ?
   
    before keccak I must convert fro 33 byte key to 65 byte key (address will be compact-independent)?
    or keccak is applied on hex string text form, not bytes?
    how checksum address with upper/lower case?

How do it with C++?