Armature: add automatic B-Bone Scale toggles.

Currently B-Bone scaling can only be controlled via their
properties, thus requiring up to 8 drivers per joint between
B-Bones to transfer scaling factors from the handle bone.

A Scale Easing option is added to multiply the easing value
by the Y scale channels to synchronize them - this produces a
natural scaling effect where both the shape of the curve and
the scale is affected.

In addition, four toggles are added for each handle, which
multiply each of the X, Y, Z and Ease values by the matching
Local Scale channel of the handle bone, thus replacing trivial
drivers. The Scale Easing option has no effect on this process
since it's easy to just enable both Length and Ease buttons.

Differential Revision: https://developer.blender.org/D9870

1 files changed, 47 insertions, 0 deletions

diff --git a/source/blender/makesrna/intern/rna_armature.c b/source/blender/makesrna/intern/rna_armature.c
index 53ccdb3b2b7..f07aae0bb15 100644
--- a/source/blender/makesrna/intern/rna_armature.c
+++ b/source/blender/makesrna/intern/rna_armature.c
@@ -769,6 +769,13 @@ void rna_def_bone_curved_common(StructRNA *srna, bool is_posebone, bool is_editb
   RNA_def_property_ui_text(prop, "Ease Out", "Length of second Bezier Handle (for B-Bones only)");
   RNA_DEF_CURVEBONE_UPDATE(prop, is_posebone, is_editbone);
 
+  if (is_posebone == false) {
+    prop = RNA_def_property(srna, "use_scale_easing", PROP_BOOLEAN, PROP_NONE);
+    RNA_def_property_ui_text(
+        prop, "Scale Easing", "Multiply the final easing values by the Scale In/Out Y factors");
+    RNA_def_property_boolean_sdna(prop, NULL, "bbone_flag", BBONE_SCALE_EASING);
+    RNA_DEF_CURVEBONE_UPDATE(prop, is_posebone, is_editbone);
+  }
 
   /* Scale In/Out */
   prop = RNA_def_property(srna, "bbone_scalein", PROP_FLOAT, PROP_XYZ);
@@ -1053,6 +1060,7 @@ static void rna_def_bone_common(StructRNA *srna, int editbone)
   RNA_def_property_ui_range(prop, 0.0f, 1000.0f, 1, RNA_TRANSLATION_PREC_DEFAULT);
   RNA_def_property_ui_text(prop, "B-Bone Display Z Width", "B-Bone Z size");
 
+  /* B-Bone Start Handle settings. */
   prop = RNA_def_property(srna, "bbone_handle_type_start", PROP_ENUM, PROP_NONE);
   RNA_def_property_enum_sdna(prop, NULL, "bbone_prev_type");
   RNA_def_property_enum_items(prop, prop_bbone_handle_type);
@@ -1077,6 +1085,26 @@ static void rna_def_bone_common(StructRNA *srna, int editbone)
   RNA_def_property_ui_text(
       prop, "B-Bone Start Handle", "Bone that serves as the start handle for the B-Bone curve");
 
+  prop = RNA_def_property(srna, "bbone_handle_use_scale_start", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_ui_text(
+      prop,
+      "Start Handle Scale",
+      "Multiply B-Bone Scale In channels by the local scale values of the start handle. "
+      "This is done after the Scale Easing option and isn't affected by it");
+  RNA_def_property_boolean_sdna(prop, NULL, "bbone_prev_flag", BBONE_HANDLE_SCALE_X);
+  RNA_def_property_array(prop, 3);
+  RNA_def_property_update(prop, 0, "rna_Armature_update_data");
+
+  prop = RNA_def_property(srna, "bbone_handle_use_ease_start", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_ui_text(
+      prop,
+      "Start Handle Ease",
+      "Multiply the B-Bone Ease In channel by the local Y scale value of the start handle. "
+      "This is done after the Scale Easing option and isn't affected by it");
+  RNA_def_property_boolean_sdna(prop, NULL, "bbone_prev_flag", BBONE_HANDLE_SCALE_EASE);
+  RNA_def_property_update(prop, 0, "rna_Armature_update_data");
+
+  /* B-Bone End Handle settings. */
   prop = RNA_def_property(srna, "bbone_handle_type_end", PROP_ENUM, PROP_NONE);
   RNA_def_property_enum_sdna(prop, NULL, "bbone_next_type");
   RNA_def_property_enum_items(prop, prop_bbone_handle_type);
@@ -1101,6 +1129,25 @@ static void rna_def_bone_common(StructRNA *srna, int editbone)
   RNA_def_property_ui_text(
       prop, "B-Bone End Handle", "Bone that serves as the end handle for the B-Bone curve");
 
+  prop = RNA_def_property(srna, "bbone_handle_use_scale_end", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_ui_text(
+      prop,
+      "End Handle Scale",
+      "Multiply B-Bone Scale Out channels by the local scale values of the end handle. "
+      "This is done after the Scale Easing option and isn't affected by it");
+  RNA_def_property_boolean_sdna(prop, NULL, "bbone_next_flag", BBONE_HANDLE_SCALE_X);
+  RNA_def_property_array(prop, 3);
+  RNA_def_property_update(prop, 0, "rna_Armature_update_data");
+
+  prop = RNA_def_property(srna, "bbone_handle_use_ease_end", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_ui_text(
+      prop,
+      "End Handle Ease",
+      "Multiply the B-Bone Ease Out channel by the local Y scale value of the end handle. "
+      "This is done after the Scale Easing option and isn't affected by it");
+  RNA_def_property_boolean_sdna(prop, NULL, "bbone_next_flag", BBONE_HANDLE_SCALE_EASE);
+  RNA_def_property_update(prop, 0, "rna_Armature_update_data");
+
   RNA_define_lib_overridable(false);
 }