Conversions like this are basically as fast as a memcpy, which will always be required in this system. Did either you or dcode try actually profiling the extra time spent?
Despite that speed is not the critical concern (asymmetric value spaces are), UTF-8 must guard against invalid byte sequences, while WTF-16, where all possible values are valid as long as byte length is a multiple of 2, does not. In practice, the guard in UTF-8 is part of the copy loop over a boundary, typically from untyped memory to untyped memory, while WTF-16 can indeed just memcpy. Unless SIMD can be utilized, the difference is about that of a loop over a load into a branch vs. a memcpy, in case this helps to quantify. Expect an additional final memcpy if the UTF-8 copy should fail before storing anything to the receiver's memory.
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Conversions like this are basically as fast as a memcpy, which will always be required in this system. Did either you or dcode try actually profiling the extra time spent?
Despite that speed is not the critical concern (asymmetric value spaces are), UTF-8 must guard against invalid byte sequences, while WTF-16, where all possible values are valid as long as byte length is a multiple of 2, does not. In practice, the guard in UTF-8 is part of the copy loop over a boundary, typically from untyped memory to untyped memory, while WTF-16 can indeed just memcpy. Unless SIMD can be utilized, the difference is about that of a loop over a load into a branch vs. a memcpy, in case this helps to quantify. Expect an additional final memcpy if the UTF-8 copy should fail before storing anything to the receiver's memory.