Sorting std::vector of vec2(x, y) points [duplicate]

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• Sorting a vector of custom objects 13 answers

How can I sort std::vector<vec2> containing vec2(x, y) coordinates based on their distance from point 0.0?

Example: I'd like to sort this:

std::vector<vec2> vec = { vec2(9,9), vec2(1,1), vec2(5,5), vec2(4,4) };

Into this:

std::vector<vec2> vec = { vec2(1,1), vec2(4,4), vec2(5,5), vec2(9,9) };