UI: Drag and Drop Constraints, Layout Updates

This patch implements the list panel system D7490 for constraints.
In this case the panels are still defined in Python.

The layouts are also updated to use subpanels and the a more organized
single column layout. There may be more tweaks necessary for the
layouts.

Reviewed By: Severin, billreynish, Mets

Differential Revision: https://developer.blender.org/D7499

2 files changed, 16 insertions, 9 deletions

diff --git a/source/blender/makesrna/intern/rna_constraint.c b/source/blender/makesrna/intern/rna_constraint.c
index 5405cb4e24a..af300f6e088 100644
--- a/source/blender/makesrna/intern/rna_constraint.c
+++ b/source/blender/makesrna/intern/rna_constraint.c
@@ -2483,7 +2483,7 @@ static void rna_def_constraint_location_limit(BlenderRNA *brna)
   prop = RNA_def_property(srna, "use_transform_limit", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "flag2", LIMIT_TRANSFORM);
   RNA_def_property_ui_text(
-      prop, "For Transform", "Transforms are affected by this constraint as well");
+      prop, "Affect Transform", "Transforms are affected by this constraint as well");
   RNA_def_property_update(prop, NC_OBJECT | ND_CONSTRAINT, "rna_Constraint_update");
 
   RNA_define_lib_overridable(false);
@@ -2556,7 +2556,7 @@ static void rna_def_constraint_rotation_limit(BlenderRNA *brna)
   prop = RNA_def_property(srna, "use_transform_limit", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "flag2", LIMIT_TRANSFORM);
   RNA_def_property_ui_text(
-      prop, "For Transform", "Transforms are affected by this constraint as well");
+      prop, "Affect Transform", "Transforms are affected by this constraint as well");
   RNA_def_property_update(prop, NC_OBJECT | ND_CONSTRAINT, "rna_Constraint_update");
 
   RNA_define_lib_overridable(false);
@@ -2644,7 +2644,7 @@ static void rna_def_constraint_size_limit(BlenderRNA *brna)
   prop = RNA_def_property(srna, "use_transform_limit", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "flag2", LIMIT_TRANSFORM);
   RNA_def_property_ui_text(
-      prop, "For Transform", "Transforms are affected by this constraint as well");
+      prop, "Affect Transform", "Transforms are affected by this constraint as well");
   RNA_def_property_update(prop, NC_OBJECT | ND_CONSTRAINT, "rna_Constraint_update");
 
   RNA_define_lib_overridable(false);
@@ -2684,7 +2684,7 @@ static void rna_def_constraint_distance_limit(BlenderRNA *brna)
   prop = RNA_def_property(srna, "use_transform_limit", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "flag", LIMITDIST_TRANSFORM);
   RNA_def_property_ui_text(
-      prop, "For Transform", "Transforms are affected by this constraint as well");
+      prop, "Affect Transform", "Transforms are affected by this constraint as well");
   RNA_def_property_update(prop, NC_OBJECT | ND_CONSTRAINT, "rna_Constraint_update");
 
   RNA_define_lib_overridable(false);
@@ -3380,7 +3380,7 @@ void RNA_def_constraint(BlenderRNA *brna)
 
   prop = RNA_def_property(srna, "show_expanded", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_flag(prop, PROP_NO_DEG_UPDATE);
-  RNA_def_property_boolean_sdna(prop, NULL, "flag", CONSTRAINT_EXPAND);
+  RNA_def_property_boolean_sdna(prop, NULL, "ui_expand_flag", 0);
   RNA_def_property_ui_text(prop, "Expanded", "Constraint's panel is expanded in UI");
   RNA_def_property_ui_icon(prop, ICON_DISCLOSURE_TRI_RIGHT, 1);
 
diff --git a/source/blender/makesrna/intern/rna_ui_api.c b/source/blender/makesrna/intern/rna_ui_api.c
index fd65b713d15..8bfee4cc26c 100644
--- a/source/blender/makesrna/intern/rna_ui_api.c
+++ b/source/blender/makesrna/intern/rna_ui_api.c
@@ -1213,6 +1213,15 @@ void RNA_api_ui_layout(StructRNA *srna)
   RNA_def_function_flag(func, FUNC_USE_CONTEXT);
   RNA_def_function_ui_description(func, "Generates the UI layout for the modifier stack");
 
+  func = RNA_def_function(srna, "template_constraints", "uiTemplateConstraints");
+  RNA_def_function_flag(func, FUNC_USE_CONTEXT);
+  RNA_def_function_ui_description(func, "Generates the panels for the constraint stack");
+  RNA_def_boolean(func,
+                  "use_bone_constraints",
+                  true,
+                  "",
+                  "Add panels for bone constraints instead of object constraints");
+
   func = RNA_def_function(srna, "template_greasepencil_modifier", "uiTemplateGpencilModifier");
   RNA_def_function_flag(func, FUNC_USE_CONTEXT);
   RNA_def_function_ui_description(func, "Generates the UI layout for grease pencil modifiers");
@@ -1251,12 +1260,10 @@ void RNA_api_ui_layout(StructRNA *srna)
                "",
                "Optionally limit the items which can be selected");
 
-  func = RNA_def_function(srna, "template_constraint", "uiTemplateConstraint");
-  RNA_def_function_ui_description(func, "Generates the UI layout for constraints");
+  func = RNA_def_function(srna, "template_constraint_header", "uiTemplateConstraintHeader");
+  RNA_def_function_ui_description(func, "Generates the header for constraint panels");
   parm = RNA_def_pointer(func, "data", "Constraint", "", "Constraint data");
   RNA_def_parameter_flags(parm, PROP_NEVER_NULL, PARM_REQUIRED | PARM_RNAPTR);
-  parm = RNA_def_pointer(func, "layout", "UILayout", "", "Sub-layout to put items in");
-  RNA_def_function_return(func, parm);
 
   func = RNA_def_function(srna, "template_preview", "uiTemplatePreview");
   RNA_def_function_ui_description(