36 lines
1.2 KiB
Plaintext
36 lines
1.2 KiB
Plaintext
Title: Optimized Incremental Delaunay
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Brief: Classic triangulation algorithm to use for one by one insertion of points, with SIMD and caching.
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Date: 1694711563
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Tags: Programming, Zig, Generation
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CSS: /style.css
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Based on [this paper](https://www.cs.umd.edu/class/spring2020/cmsc754/Lects/lect13-delaun-alg.pdf)
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Full usable isolated code is [here](/articles/incremental-delaunay/incremental-delaunay.zig.txt).
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### Usage example ###
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```zig
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var gpa = std.heap.GeneralPurposeAllocator(.{}){};
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defer std.debug.assert(gpa.deinit() == .ok);
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var triangulator = try Delaunay.Builder.init(gpa.allocator(), Delaunay.Area{-1, -1, 1, 1});
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const point_count = 128;
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var prng = std.rand.DefaultPrng.init(123123);
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const rng = prng.random();
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for (0..point_count) |_| {
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const x = rng.float(f32) * 2 - 1;
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const y = rng.float(f32) * 2 - 1;
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try triangulator.insertAtRandom(Delaunay.Vertex{ x, y }, rng);
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}
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var triangles: [point_count * 2 + 2]gfx.triangle.ScreenspaceTriangle = undefined;
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for (&triangles, triangulator.triangles.items) |*out, in| {
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out.a = triangulator.vertices.items[in.points[0]];
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out.b = triangulator.vertices.items[in.points[1]];
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out.c = triangulator.vertices.items[in.points[2]];
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}
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```
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