Curve: Improve NURBS knot generation modes

This patch enables all 8 combinations of Nurbs modes: Cyclic,
Bezier and Endpoint. Also removes restriction on Bezier Nurbs order.

The most significant changes are mode combinations bringing new
meaning. In D13891 is a scheme showing NURBS with same control
points in a modes, and also further description of each possible case.

Differential Revision: https://developer.blender.org/D13891

1 files changed, 50 insertions, 13 deletions

diff --git a/source/blender/makesrna/intern/rna_curve.c b/source/blender/makesrna/intern/rna_curve.c
index 891de95a2a2..2c1ed483de6 100644
--- a/source/blender/makesrna/intern/rna_curve.c
+++ b/source/blender/makesrna/intern/rna_curve.c
@@ -562,6 +562,38 @@ static void rna_Curve_offset_set(PointerRNA *ptr, float value)
   cu->offset = 1.0f + value;
 }
 
+static int rna_Nurb_valid_message_u_length(PointerRNA *ptr)
+{
+  char buff[64];
+  Nurb *nu = (Nurb *)ptr->data;
+  BKE_nurb_valid_message(
+      nu->pntsu, nu->orderu, nu->flagu, nu->type, nu->pntsv > 1, "U", buff, sizeof(buff));
+  return strlen(buff);
+}
+
+static void rna_Nurb_valid_message_u(PointerRNA *ptr, char *value)
+{
+  Nurb *nu = (Nurb *)ptr->data;
+  BKE_nurb_valid_message(
+      nu->pntsu, nu->orderu, nu->flagu, nu->type, nu->pntsv > 1, "U", value, 64);
+}
+
+static int rna_Nurb_valid_message_v_length(PointerRNA *ptr)
+{
+  char buff[64];
+  Nurb *nu = (Nurb *)ptr->data;
+  BKE_nurb_valid_message(
+      nu->pntsv, nu->orderv, nu->flagv, nu->type, nu->pntsv > 1, "V", buff, sizeof(buff));
+  return strlen(buff);
+}
+
+static void rna_Nurb_valid_message_v(PointerRNA *ptr, char *value)
+{
+  Nurb *nu = (Nurb *)ptr->data;
+  BKE_nurb_valid_message(
+      nu->pntsv, nu->orderv, nu->flagv, nu->type, nu->pntsv > 1, "V", value, 64);
+}
+
 static int rna_Curve_body_length(PointerRNA *ptr);
 static void rna_Curve_body_get(PointerRNA *ptr, char *value)
 {
@@ -1995,24 +2027,20 @@ static void rna_def_curve_nurb(BlenderRNA *brna)
   RNA_def_property_ui_text(prop, "Cyclic V", "Make this surface a closed loop in the V direction");
   RNA_def_property_update(prop, 0, "rna_Nurb_update_cyclic_v");
 
-  /* NOTE: endpoint and bezier flags should never be on at the same time! */
   prop = RNA_def_property(srna, "use_endpoint_u", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "flagu", CU_NURB_ENDPOINT);
   RNA_def_property_clear_flag(prop, PROP_ANIMATABLE);
   RNA_def_property_ui_text(
       prop,
       "Endpoint U",
-      "Make this nurbs curve or surface meet the endpoints in the U direction "
-      "(Cyclic U must be disabled)");
+      "Make this nurbs curve or surface meet the endpoints in the U direction");
   RNA_def_property_update(prop, 0, "rna_Nurb_update_knot_u");
 
   prop = RNA_def_property(srna, "use_endpoint_v", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "flagv", CU_NURB_ENDPOINT);
   RNA_def_property_clear_flag(prop, PROP_ANIMATABLE);
-  RNA_def_property_ui_text(prop,
-                           "Endpoint V",
-                           "Make this nurbs surface meet the endpoints in the V direction "
-                           "(Cyclic V must be disabled)");
+  RNA_def_property_ui_text(
+      prop, "Endpoint V", "Make this nurbs surface meet the endpoints in the V direction ");
   RNA_def_property_update(prop, 0, "rna_Nurb_update_knot_v");
 
   prop = RNA_def_property(srna, "use_bezier_u", PROP_BOOLEAN, PROP_NONE);
@@ -2021,19 +2049,28 @@ static void rna_def_curve_nurb(BlenderRNA *brna)
   RNA_def_property_ui_text(
       prop,
       "Bezier U",
-      "Make this nurbs curve or surface act like a Bezier spline in the U direction "
-      "(Order U must be 3 or 4, Cyclic U must be disabled)");
+      "Make this nurbs curve or surface act like a Bezier spline in the U direction");
   RNA_def_property_update(prop, 0, "rna_Nurb_update_knot_u");
 
   prop = RNA_def_property(srna, "use_bezier_v", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "flagv", CU_NURB_BEZIER);
   RNA_def_property_clear_flag(prop, PROP_ANIMATABLE);
-  RNA_def_property_ui_text(prop,
-                           "Bezier V",
-                           "Make this nurbs surface act like a Bezier spline in the V direction "
-                           "(Order V must be 3 or 4, Cyclic V must be disabled)");
+  RNA_def_property_ui_text(
+      prop, "Bezier V", "Make this nurbs surface act like a Bezier spline in the V direction");
   RNA_def_property_update(prop, 0, "rna_Nurb_update_knot_v");
 
+  prop = RNA_def_property(srna, "valid_message_u", PROP_STRING, PROP_NONE);
+  RNA_def_property_clear_flag(prop, PROP_EDITABLE);
+  RNA_def_property_string_funcs(
+      prop, "rna_Nurb_valid_message_u", "rna_Nurb_valid_message_u_length", NULL);
+  RNA_def_property_ui_text(prop, "Valid U", "Validation message for NURBS definition in U");
+
+  prop = RNA_def_property(srna, "valid_message_v", PROP_STRING, PROP_NONE);
+  RNA_def_property_clear_flag(prop, PROP_EDITABLE);
+  RNA_def_property_string_funcs(
+      prop, "rna_Nurb_valid_message_v", "rna_Nurb_valid_message_v_length", NULL);
+  RNA_def_property_ui_text(prop, "Valid V", "Validation message for NURBS definition in V");
+
   prop = RNA_def_property(srna, "use_smooth", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "flag", CU_SMOOTH);
   RNA_def_property_ui_text(prop, "Smooth", "Smooth the normals of the surface or beveled curve");