Geometry Nodes: Begin conversion to new curves

This commit changes `CurveComponent` to store the new curve
type by adding conversions to and from `CurveEval` in most nodes.
This will temporarily make performance of curves in geometry nodes
much worse, but as functionality is implemented for the new type
and it is used in more places, performance will become better than
before.

We still use `CurveEval` for drawing curves, because the new `Curves`
data-block has no evaluated points yet. So the `Curve` ID is still
generated for rendering in the same way as before. It's also still
needed for drawing curve object edit mode overlays.

The old curve component isn't removed yet, because it is still used
to implement the conversions to and from `CurveEval`.

A few more attributes are added to make this possible:
- `nurbs_weight`: The weight for each control point on NURBS curves.
- `nurbs_order`: The order of the NURBS curve
- `knots_mode`: Necessary for conversion, not defined yet.
- `handle_type_{left/right}`: An 8 bit integer attribute.

Differential Revision: https://developer.blender.org/D14145

1 files changed, 14 insertions, 12 deletions

diff --git a/source/blender/blenkernel/intern/geometry_set.cc b/source/blender/blenkernel/intern/geometry_set.cc
index 13441b4914a..73572e30d61 100644
--- a/source/blender/blenkernel/intern/geometry_set.cc
+++ b/source/blender/blenkernel/intern/geometry_set.cc
@@ -7,6 +7,7 @@
 
 #include "BKE_attribute.h"
 #include "BKE_attribute_access.hh"
+#include "BKE_curves.hh"
 #include "BKE_geometry_set.hh"
 #include "BKE_lib_id.h"
 #include "BKE_mesh.h"
@@ -186,8 +187,9 @@ bool GeometrySet::compute_boundbox_without_instances(float3 *r_min, float3 *r_ma
   if (volume != nullptr) {
     have_minmax |= BKE_volume_min_max(volume, *r_min, *r_max);
   }
-  const CurveEval *curve = this->get_curve_for_read();
-  if (curve != nullptr) {
+  const Curves *curves = this->get_curve_for_read();
+  if (curves != nullptr) {
+    std::unique_ptr<CurveEval> curve = curves_to_curve_eval(*curves);
     /* Using the evaluated positions is somewhat arbitrary, but it is probably expected. */
     have_minmax |= curve->bounds_min_max(*r_min, *r_max, true);
   }
@@ -258,7 +260,7 @@ const Volume *GeometrySet::get_volume_for_read() const
   return (component == nullptr) ? nullptr : component->get_for_read();
 }
 
-const CurveEval *GeometrySet::get_curve_for_read() const
+const Curves *GeometrySet::get_curve_for_read() const
 {
   const CurveComponent *component = this->get_component_for_read<CurveComponent>();
   return (component == nullptr) ? nullptr : component->get_for_read();
@@ -285,7 +287,7 @@ bool GeometrySet::has_volume() const
 bool GeometrySet::has_curve() const
 {
   const CurveComponent *component = this->get_component_for_read<CurveComponent>();
-  return component != nullptr && component->has_curve();
+  return component != nullptr && component->has_curves();
 }
 
 bool GeometrySet::has_realized_data() const
@@ -327,12 +329,12 @@ GeometrySet GeometrySet::create_with_pointcloud(PointCloud *pointcloud,
   return geometry_set;
 }
 
-GeometrySet GeometrySet::create_with_curve(CurveEval *curve, GeometryOwnershipType ownership)
+GeometrySet GeometrySet::create_with_curve(Curves *curves, GeometryOwnershipType ownership)
 {
   GeometrySet geometry_set;
-  if (curve != nullptr) {
+  if (curves != nullptr) {
     CurveComponent &component = geometry_set.get_component_for_write<CurveComponent>();
-    component.replace(curve, ownership);
+    component.replace(curves, ownership);
   }
   return geometry_set;
 }
@@ -351,18 +353,18 @@ void GeometrySet::replace_mesh(Mesh *mesh, GeometryOwnershipType ownership)
   component.replace(mesh, ownership);
 }
 
-void GeometrySet::replace_curve(CurveEval *curve, GeometryOwnershipType ownership)
+void GeometrySet::replace_curve(Curves *curves, GeometryOwnershipType ownership)
 {
-  if (curve == nullptr) {
+  if (curves == nullptr) {
     this->remove<CurveComponent>();
     return;
   }
-  if (curve == this->get_curve_for_read()) {
+  if (curves == this->get_curve_for_read()) {
     return;
   }
   this->remove<CurveComponent>();
   CurveComponent &component = this->get_component_for_write<CurveComponent>();
-  component.replace(curve, ownership);
+  component.replace(curves, ownership);
 }
 
 void GeometrySet::replace_pointcloud(PointCloud *pointcloud, GeometryOwnershipType ownership)
@@ -411,7 +413,7 @@ Volume *GeometrySet::get_volume_for_write()
   return component == nullptr ? nullptr : component->get_for_write();
 }
 
-CurveEval *GeometrySet::get_curve_for_write()
+Curves *GeometrySet::get_curve_for_write()
 {
   CurveComponent *component = this->get_component_ptr<CurveComponent>();
   return component == nullptr ? nullptr : component->get_for_write();