From 6594e802ab94ff1124d9157deb0ca760981e3f34 Mon Sep 17 00:00:00 2001
From: Hans Goudey <h.goudey@me.com>
Date: Mon, 28 Feb 2022 17:20:37 -0500
Subject: [PATCH] Curves: Add method to access cyclic attribute

Avoids the need to use the attribute API to access this commonly
used builtin attribute.
---
 source/blender/blenkernel/BKE_curves.hh        |  3 +++
 .../blenkernel/intern/curves_geometry.cc       | 18 ++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/source/blender/blenkernel/BKE_curves.hh b/source/blender/blenkernel/BKE_curves.hh
index 209f892c651..6fa7de49eb0 100644
--- a/source/blender/blenkernel/BKE_curves.hh
+++ b/source/blender/blenkernel/BKE_curves.hh
@@ -119,6 +119,9 @@ class CurvesGeometry : public ::CurvesGeometry {
   Span<int> offsets() const;
   MutableSpan<int> offsets();
 
+  VArray<bool> cyclic() const;
+  MutableSpan<bool> cyclic();
+
   /* --------------------------------------------------------------------
    * Operations.
    */
diff --git a/source/blender/blenkernel/intern/curves_geometry.cc b/source/blender/blenkernel/intern/curves_geometry.cc
index 68797942b56..3eea579230a 100644
--- a/source/blender/blenkernel/intern/curves_geometry.cc
+++ b/source/blender/blenkernel/intern/curves_geometry.cc
@@ -18,6 +18,7 @@ namespace blender::bke {
 static const std::string ATTR_POSITION = "position";
 static const std::string ATTR_RADIUS = "radius";
 static const std::string ATTR_CURVE_TYPE = "curve_type";
+static const std::string ATTR_CYCLIC = "cyclic";
 
 /* -------------------------------------------------------------------- */
 /** \name Constructors/Destructor
@@ -168,6 +169,23 @@ Span<int> CurvesGeometry::offsets() const
   return {this->curve_offsets, this->curve_size + 1};
 }
 
+VArray<bool> CurvesGeometry::cyclic() const
+{
+  const bool *data = (const bool *)CustomData_get_layer_named(
+      &this->curve_data, CD_PROP_INT8, ATTR_CURVE_TYPE.c_str());
+  if (data != nullptr) {
+    return VArray<bool>::ForSpan(Span(data, this->curve_size));
+  }
+  return VArray<bool>::ForSingle(false, this->curve_size);
+}
+
+MutableSpan<bool> CurvesGeometry::cyclic()
+{
+  bool *data = (bool *)CustomData_add_layer_named(
+      &this->curve_data, CD_PROP_BOOL, CD_CALLOC, nullptr, this->curve_size, ATTR_CYCLIC.c_str());
+  return {data, this->curve_size};
+}
+
 void CurvesGeometry::resize(const int point_size, const int curve_size)
 {
   if (point_size != this->point_size) {