类型 char* 转化为 ::rust::Vec<::std::uint8_t> 的问题。The problem of converting type char* to ::rust::Vec<::std::uint8_t>. about dora HOT 6 OPEN

I'm not an expert of C++, but maybe try adding .data() at the end:

std::memcpy(PointCloud2.data.data(), output_data, output_data_len);

From memory alone, I think that PointCloud2.data is a standard vector in C++

https://chat.openai.com/c/c42af36d-9385-4db5-a168-c1337d570335

p.s: note that you can use ```c++ for syntax highlighting

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See https://cxx.rs/binding/vec.html for the type definition of rust::Vec<T>. While it's similar to a std::vector, it's a different type without any direction conversion. Unfortunately, I don't see any more efficient way to push multiple values either.

std::memcpy(PointCloud2.data.data(), output_data, output_data_len);

This is unsafe and will lead to undefined behavior if output_data_len is greater than PointCloud2.data.size().

A possible solution could be to generate two versions of each message type: one based on Rust types and one based on C++ types. The version based on C++ types would then contain normal std::vector fields instead of rust::Vec. Subscribe methods would only support the version based on Rust-types, but publish methods could support both types. The drawback is that it duplicates all message types, which could be confusing. What do you think about this approach @ShoreFlower?

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To avoid the boilerplate of the for loop, you should be able to use back_inserter together with std::copy.

Doing a pointer copy would require a public set_len method, which is being discussed upstream. However, apparently such a function isn't even available for the standard C++ vector type.

If you're concerned about efficiency, you should try doing a benchmark with link-time optimization enabled. I can imagine that the compiler/linker optimizes the for loop and push_back calls to some quite efficient code.

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To make the push_back operation cheap you can call reserve with the required capacity beforehand. Then no reallocation is required anymore.

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Thank you for your answer, for having used std::copy can solve the data problem.
std::copy(output_data + 16, output_data + output_data_len, std::back_inserter(PointCloud2.data));

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