initial commit

1 files changed, 23 insertions, 0 deletions

diff --git a/src/shared/math.cc b/src/shared/math.cc
new file mode 100644
index 0000000..80eba81
--- /dev/null
+++ b/src/shared/math.cc
@@ -0,0 +1,23 @@
+#include "shared/math.hh"
+
+namespace shared {
+namespace math {
+
+glm::vec3 angle_to_dir(const angles& ang) noexcept {
+    const float x = std::cos(ang.pitch) * std::cos(ang.yaw);
+    const float y = std::sin(ang.pitch);
+    const float z = std::cos(ang.pitch) * std::sin(ang.yaw);
+    return {x, y, z};
+}
+
+bool is_inside_draw(const coords& a, const coords& b,
+                    const std::int32_t draw_distance) noexcept {
+    const auto x2 = (a.x - b.x) * (a.x - b.x);
+    const auto z2 = (a.z - b.z) * (a.z - b.z);
+    const auto dd2 = draw_distance * draw_distance;
+
+    return (x2 < dd2 - z2) && (z2 < dd2 - x2);
+}
+
+} // namespace math
+} // namespace shared