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<title>Hash.combine — Ludic</title>
<meta name="description" content="Fold several ints into one deterministic seed.">
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<div class="crumbs"><a href="api.html">API Reference</a> <span>›</span> <a href="ns-hash.html">Hash</a> <span>›</span> <span class="here">Hash.combine</span></div>
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<span class="kind-badge kind-method">method</span>
<h1 id="top">Hash.combine</h1>
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<code class="sig">Hash.combine(...) -&gt; int</code>
<div class="desc"><p>Mixes any number of integers into a single 32-bit value. It folds the arguments left to right with the classic hash-combine step (each value is spread with the golden-ratio constant <code>0x9e3779b9</code> and stirred into the running seed), so the result depends on every input and on their order — <code>Hash.combine(1, 2, 3)</code> and <code>Hash.combine(3, 2, 1)</code> differ. The whole point is a per-thing deterministic seed: hash a world seed with a chunk's coordinates to drive procedural generation, so the same chunk always regenerates identically. Pair it with the noise and random libraries, which take a seed.</p></div>
<div class="examples"><h2>Example</h2><pre data-lang="ludic">program ChunkSeed {
entry {
let world_seed = 1337
let cx = 4
let cy = -2
let seed = Hash.combine(world_seed, cx, cy) # this chunk's stable seed
print(seed)
print(Hash.combine(world_seed, cx, cy) == seed) # 1 — reproducible
}
}</pre></div>
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