Geometry Nodes: Curve Parameter Node

This commit adds a field input node that outputs the fraction of the
total length of the spline on each control point. This is useful for
anything that involves varying a value depending on how far along
the spline it is.

It also works when evaluated on the spline domain, where it outputs
the fraction of the total length of all of the splines at the start.

The operation isn't as well defined for NURB splines for the reasons
noted in the code comment. That can be said explicitly in the docs.

Differential Revision: https://developer.blender.org/D12548

1 files changed, 1 insertions, 0 deletions

diff --git a/source/blender/nodes/NOD_geometry.h b/source/blender/nodes/NOD_geometry.h
index 91d79d9e7b6..24f60263d8a 100644
--- a/source/blender/nodes/NOD_geometry.h
+++ b/source/blender/nodes/NOD_geometry.h
@@ -59,6 +59,7 @@ void register_node_type_geo_convex_hull(void);
 void register_node_type_geo_curve_endpoints(void);
 void register_node_type_geo_curve_fill(void);
 void register_node_type_geo_curve_length(void);
+void register_node_type_geo_curve_parameter(void);
 void register_node_type_geo_curve_sample(void);
 void register_node_type_geo_curve_primitive_bezier_segment(void);
 void register_node_type_geo_curve_primitive_circle(void);