[Bf-blender-cvs] [d7aa4812317] geometry-nodes-curve-support: Splines: Add comments

[Hans Goudey]

Commit: d7aa48123174c08a07366cfb7f5e3544b5c2fbb0
Author: Hans Goudey
Date:   Thu Apr 22 12:24:52 2021 -0500
Branches: geometry-nodes-curve-support
https://developer.blender.org/rBd7aa48123174c08a07366cfb7f5e3544b5c2fbb0

Splines: Add comments

===================================================================

M	source/blender/blenkernel/intern/spline_nurbs.cc

===================================================================

diff --git a/source/blender/blenkernel/intern/spline_nurbs.cc b/source/blender/blenkernel/intern/spline_nurbs.cc
index 4181e8c6df6..f81dec2d8f3 100644
--- a/source/blender/blenkernel/intern/spline_nurbs.cc
+++ b/source/blender/blenkernel/intern/spline_nurbs.cc
@@ -301,6 +301,7 @@ static void calculate_basis_for_point(const float parameter,
     }
   }
 
+  /* Shrink the range of calculated values to avoid storing unecessary zeros. */
   while (basis_buffer[start] == 0.0f && start < end) {
     start++;
   }
@@ -334,6 +335,8 @@ void NURBSpline::calculate_basis_cache() const
 
   MutableSpan<BasisCache> basis_cache = this->weight_cache_;
 
+  /* This buffer is reused by each basis calculation to store temporary values.
+   * Theoretically it could likely be optimized away in the future. */
   Array<float> basis_buffer(this->knots_size());
 
   const float start = knots[order - 1];