Complete imaging and meshing integration gate (#44)

crates/libremetaverse-prim-mesher/benches/meshing.rs

@@ -0,0 +1,54 @@
+use std::alloc::System;
+use std::hint::black_box;
+use std::time::Instant;
+
+use libremetaverse_prim_mesher::{PathType, PrimMesh};
+use stats_alloc::{INSTRUMENTED_SYSTEM, Region, StatsAlloc};
+
+#[global_allocator]
+static ALLOCATOR: &StatsAlloc<System> = &INSTRUMENTED_SYSTEM;
+
+fn main() {
+    let mut mesh = PrimMesh::new(128, 0.03, 0.97, 0.35, 64)
+        .expect("large benchmark profile must fit the documented bounds");
+    mesh.viewer_mode = true;
+    mesh.calc_vertex_normals = true;
+    mesh.path_cut_begin = 0.02;
+    mesh.path_cut_end = 0.98;
+    mesh.hole_size_x = 0.7;
+    mesh.hole_size_y = 0.3;
+    mesh.twist_begin = -45;
+    mesh.twist_end = 270;
+    mesh.taper_x = 0.15;
+    mesh.taper_y = -0.1;
+    mesh.skew = 0.2;
+    mesh.radius = 0.1;
+    mesh.revolutions = 1.5;
+    mesh.steps_per_revolution = 96;
+
+    let allocation_region = Region::new(ALLOCATOR);
+    let started = Instant::now();
+    mesh.extrude(PathType::Circular)
+        .expect("bounded circular extrusion");
+    let indexer = mesh
+        .get_vertex_indexer()
+        .expect("checked viewer indexing")
+        .expect("viewer-mode indexer");
+    let elapsed = started.elapsed();
+    let allocation_stats = allocation_region.change();
+
+    assert!(!mesh.coords.is_empty());
+    assert!(!mesh.faces.is_empty());
+    assert!(!mesh.viewer_faces.is_empty());
+    assert!(mesh.viewer_faces.len() <= mesh.faces.len());
+    black_box((&mesh, &indexer));
+    println!(
+        "meshing pipeline: {} coordinates, {} triangles, {} prim faces in {elapsed:?}, {} allocations, {} reallocations, {} bytes allocated",
+        mesh.coords.len(),
+        mesh.faces.len(),
+        indexer.num_prim_faces,
+        allocation_stats.allocations,
+        allocation_stats.reallocations,
+        allocation_stats.bytes_allocated,
+    );
+}