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Use current time instead of hardcoded value as random seed #15

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Use current time instead of hardcoded value as random seed #15

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2 changes: 1 addition & 1 deletion src/cloud.cpp
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Expand Up @@ -95,7 +95,7 @@ void Cloud::Reset() {
droplet.Reset();

// Reset all the RNG stuff
mt.seed(0x1234567);
mt.seed(high_resolution_clock::now().time_since_epoch().count());
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@st3w st3w Dec 23, 2021 •
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Hello @xV8IHmeZIAStqNFV8iKGyyertVIet15TS6gWrIV,

tl;dr Add a static_cast<uint32_t>, and this should be fine.

I made this deterministic to make it easier to debug things during development. I have no objections to making it truly random now.

However, count() will return a 64-bit unsigned integer, but seed() takes a 32-bit unsigned integer (mt19937 takes a 32-bit seed, mt19937_64 takes a 64-bit seed). So some compilers will warn that this operation performs an implicit narrowing conversion. If you add a static_cast<uint32_t>, then it will be fine.

A better approach would be something like:

random_device rd;
seed_seq sseq{rd(), rd()}; // 64-bits of random state used for seeding
mt.seed(sseq);

Edit: Also, I will be away from my development computer until Jan 10th. So this won't get merged for a while...


int8_t lowPair, highPair;
if (_numColorPairs < 3) {
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