Geometry Nodes: Port sample curves node to new data-block

Use the newer more generic sampling and interpolation functions
developed recently (ab444a80a280) instead of the `CurveEval` type.
Functions are split up a bit more internally, to allow a separate mode
for supplying the curve index directly in the future (T92474).

In one basic test, the performance seems mostly unchanged from 3.1.

Differential Revision: https://developer.blender.org/D14621

1 files changed, 28 insertions, 15 deletions

diff --git a/source/blender/blenlib/BLI_length_parameterize.hh b/source/blender/blenlib/BLI_length_parameterize.hh
index 1b494c021a3..d81bcbe1e7a 100644
--- a/source/blender/blenlib/BLI_length_parameterize.hh
+++ b/source/blender/blenlib/BLI_length_parameterize.hh
@@ -6,6 +6,7 @@
  * \ingroup bli
  */
 
+#include "BLI_index_mask.hh"
 #include "BLI_math_base.hh"
 #include "BLI_math_color.hh"
 #include "BLI_math_vector.hh"
@@ -41,26 +42,38 @@ void accumulate_lengths(const Span<T> values, const bool cyclic, MutableSpan<flo
 }
 
 template<typename T>
-inline void interpolate(const Span<T> src,
-                        const Span<int> indices,
-                        const Span<float> factors,
-                        MutableSpan<T> dst)
+inline void interpolate_to_masked(const Span<T> src,
+                                  const Span<int> indices,
+                                  const Span<float> factors,
+                                  const IndexMask dst_mask,
+                                  MutableSpan<T> dst)
 {
   BLI_assert(indices.size() == factors.size());
-  BLI_assert(indices.size() == dst.size());
+  BLI_assert(indices.size() == dst_mask.size());
   const int last_src_index = src.size() - 1;
 
-  for (const int i : dst.index_range()) {
-    const int prev_index = indices[i];
-    const float factor = factors[i];
-    const bool is_cyclic_case = prev_index == last_src_index;
-    if (is_cyclic_case) {
-      dst[i] = math::interpolate(src.last(), src.first(), factor);
+  dst_mask.to_best_mask_type([&](auto dst_mask) {
+    for (const int i : IndexRange(dst_mask.size())) {
+      const int prev_index = indices[i];
+      const float factor = factors[i];
+      const bool is_cyclic_case = prev_index == last_src_index;
+      if (is_cyclic_case) {
+        dst[dst_mask[i]] = math::interpolate(src.last(), src.first(), factor);
+      }
+      else {
+        dst[dst_mask[i]] = math::interpolate(src[prev_index], src[prev_index + 1], factor);
+      }
     }
-    else {
-      dst[i] = math::interpolate(src[prev_index], src[prev_index + 1], factor);
-    }
-  }
+  });
+}
+
+template<typename T>
+inline void interpolate(const Span<T> src,
+                        const Span<int> indices,
+                        const Span<float> factors,
+                        MutableSpan<T> dst)
+{
+  interpolate_to_masked(src, indices, factors, dst.index_range(), dst);
 }
 
 /**