Specialize function by argument values known at compile time in C++

I have some function with 2 arguments: distance and radius

float expensive_function(float distance, float radius) {
    return distance + radius;
}

The whole project only uses 2 different radiuses and they both are known at compile time (1.2f and 3.4f). Is there a way to specialize this function knowing that? I would like something like that, but it doesn’t compile:

template <float RADIUS>
float expensive_function(float distance) {
    return distance + RADIUS;
}

expensive_function<1.2f>(run_time_distance);
expensive_function<3.4f>(run_time_distance);

Compiler says:
Candidate template ignored: invalid explicitly-specified argument for template parameter 'RADIUS'
and
No matching function for call to 'expensive_function'

I’m not very familiar with C++ template programming, so I didn’t expect it to work. I don’t know if what I’m looking for even possible. I just want to make sure compiler will generate the most performant code for either cases, plus it’s better semantically in my opinion.

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