Curves: Add a utility to count curves of each type

This commit adds a utility that returns an array with the number
of curves of every type. One use case for this is detecting whether
to remove handle or NURBS attributes when changing curve types.
It's best to avoid using this when it's not necessary, but sometimes
it can't really be avoided, and having a utility at least makes using
an optimized version simple.

In the future, this information can be cached in the curves runtime.

Differential Revision: https://developer.blender.org/D14448

1 files changed, 2 insertions, 0 deletions

diff --git a/source/blender/blenkernel/BKE_curves.hh b/source/blender/blenkernel/BKE_curves.hh
index 0f2ae8a02a6..96963dcbd8d 100644
--- a/source/blender/blenkernel/BKE_curves.hh
+++ b/source/blender/blenkernel/BKE_curves.hh
@@ -146,6 +146,8 @@ class CurvesGeometry : public ::CurvesGeometry {
   MutableSpan<int8_t> curve_types();
 
   bool has_curve_with_type(const CurveType type) const;
+  /** Return the number of curves with each type. */
+  std::array<int, CURVE_TYPES_NUM> count_curve_types() const;
 
   MutableSpan<float3> positions();
   Span<float3> positions() const;