Splines: Add a method for reversing a Spline

This moved the spline reversing logic out of the Curve Reverse geometry
node and into the spline class. This allows a spline to reverse itself
with a call to `my_spline.reverse()`

The base class will reverse position, radii & tilt, while specialized
versions are created for Bezier and Nurbs splines to reverse the
additional data that these classes encapsulate.

Differential Revision: https://developer.blender.org/D12501

1 files changed, 29 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/spline_base.cc b/source/blender/blenkernel/intern/spline_base.cc
index 732fabc6582..a8871777420 100644
--- a/source/blender/blenkernel/intern/spline_base.cc
+++ b/source/blender/blenkernel/intern/spline_base.cc
@@ -19,6 +19,8 @@
 #include "BLI_task.hh"
 #include "BLI_timeit.hh"
 
+#include "BKE_attribute_access.hh"
+#include "BKE_attribute_math.hh"
 #include "BKE_spline.hh"
 
 #include "FN_generic_virtual_array.hh"
@@ -28,6 +30,8 @@ using blender::float3;
 using blender::IndexRange;
 using blender::MutableSpan;
 using blender::Span;
+using blender::attribute_math::convert_to_static_type;
+using blender::bke::AttributeIDRef;
 using blender::fn::GMutableSpan;
 using blender::fn::GSpan;
 using blender::fn::GVArray;
@@ -110,6 +114,31 @@ void Spline::transform(const blender::float4x4 &matrix)
   this->mark_cache_invalid();
 }
 
+void Spline::reverse()
+{
+  this->positions().reverse();
+  this->radii().reverse();
+  this->tilts().reverse();
+
+  this->attributes.foreach_attribute(
+      [&](const AttributeIDRef &id, const AttributeMetaData &meta_data) {
+        std::optional<blender::fn::GMutableSpan> attribute = this->attributes.get_for_write(id);
+        if (!attribute) {
+          BLI_assert_unreachable();
+          return false;
+        }
+        convert_to_static_type(meta_data.data_type, [&](auto dummy) {
+          using T = decltype(dummy);
+          attribute->typed<T>().reverse();
+        });
+        return true;
+      },
+      ATTR_DOMAIN_POINT);
+
+  this->reverse_impl();
+  this->mark_cache_invalid();
+}
+
 int Spline::evaluated_edges_size() const
 {
   const int eval_size = this->evaluated_points_size();