1 files changed, 52 insertions, 0 deletions
diff --git a/tools/chilbert_svg.cpp b/tools/chilbert_svg.cpp
new file mode 100644
index 0000000..140b99a
--- /dev/null
+++ b/tools/chilbert_svg.cpp
@@ -0,0 +1,52 @@
+// Copyright 2018-2022 David Robillard <d@drobilla.net>
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "chilbert/chilbert.hpp"
+
+#include <array>
+#include <climits>
+#include <cmath>
+#include <cstdint>
+#include <cstdio>
+#include <cstdlib>
+
+int
+main(int argc, char** argv)
+{
+  if (argc != 2) {
+    fprintf(stderr, "Usage: %s NUM_POINTS\n", argv[0]);
+    return 1;
+  }
+
+  const unsigned long num_points = std::strtoul(argv[1], nullptr, 10);
+  if (num_points == 0 || num_points == ULONG_MAX) {
+    fprintf(stderr, "Usage: %s NUM_POINTS\n", argv[0]);
+    return 1;
+  }
+
+  const uint32_t w =
+    static_cast<uint32_t>(sqrt(1U << static_cast<uint32_t>(ceil(
+                                 log2(static_cast<double>(num_points)))))) -
+    1U;
+
+  // Header
+  printf("<svg xmlns='http://www.w3.org/2000/svg'"
+         " version='1.2' baseProfile='tiny' viewBox='0 0 %u %u'>\n",
+         w,
+         w);
+  printf("<desc>Hilbert Curve</desc>\n");
+  printf("<polyline vector-effect='non-scaling-stroke' fill='none' "
+         "stroke='black' stroke-width='1' points='");
+
+  // One polyline through all vertices
+  for (uint64_t i = 0; i <= num_points; ++i) {
+    std::array<uint32_t, 2> point{};
+    chilbert::index_to_coords(point, 32, 2, i);
+    printf("%u,%u ", point[0], point[1]);
+  }
+
+  // Close off document
+  printf("' />\n</svg>\n");
+
+  return 0;
+}