Geometry Nodes: Field on Domain Node

As described in T98943, this commit adds a node that can
evaluate a field on a separate domain in a larger field context.
This is potentially useful in many cases, to avoid relying on
a separate capture attribute node, which can make it easier
to build reusable fields that don't need geometry inputs.

Internally, the node just evaluates the input field in the larger
field context and then uses the generic domain interpolation,
so the code is simple. One future optimization might be using
the input selection to only evaluate part of the input field, but
then the selection has to be interpolated as well, and that might
not always be worth it.

Differential Revision: https://developer.blender.org/D15289

1 files changed, 19 insertions, 0 deletions

diff --git a/source/blender/makesrna/intern/rna_nodetree.c b/source/blender/makesrna/intern/rna_nodetree.c
index 65a8d8bf24a..1a8f47605a3 100644
--- a/source/blender/makesrna/intern/rna_nodetree.c
+++ b/source/blender/makesrna/intern/rna_nodetree.c
@@ -10702,6 +10702,25 @@ static void def_geo_field_at_index(StructRNA *srna)
   RNA_def_property_update(prop, NC_NODE | NA_EDITED, "rna_GeometryNode_socket_update");
 }
 
+static void def_geo_field_on_domain(StructRNA *srna)
+{
+  PropertyRNA *prop;
+
+  prop = RNA_def_property(srna, "domain", PROP_ENUM, PROP_NONE);
+  RNA_def_property_enum_sdna(prop, NULL, "custom1");
+  RNA_def_property_enum_items(prop, rna_enum_attribute_domain_items);
+  RNA_def_property_ui_text(prop, "Domain", "Domain the field is evaluated in");
+  RNA_def_property_update(prop, NC_NODE | NA_EDITED, "rna_GeometryNode_socket_update");
+
+  prop = RNA_def_property(srna, "data_type", PROP_ENUM, PROP_NONE);
+  RNA_def_property_enum_sdna(prop, NULL, "custom2");
+  RNA_def_property_enum_items(prop, rna_enum_attribute_type_items);
+  RNA_def_property_enum_funcs(
+      prop, NULL, NULL, "rna_GeometryNodeAttributeType_type_with_socket_itemf");
+  RNA_def_property_ui_text(prop, "Data Type", "");
+  RNA_def_property_update(prop, NC_NODE | NA_EDITED, "rna_GeometryNode_socket_update");
+}
+
 static void def_geo_scale_elements(StructRNA *srna)
 {
   PropertyRNA *prop;