[Bf-blender-cvs] [99eafedf8ba] temp-angavrilov-constraints: Limit Rotation: add an Euler Order option and orthogonalize the matrix.

[Alexander Gavrilov]

Commit: 99eafedf8ba606a8760f23fee9755734512d125c
Author: Alexander Gavrilov
Date:   Sun Nov 22 14:17:21 2020 +0300
Branches: temp-angavrilov-constraints
https://developer.blender.org/rB99eafedf8ba606a8760f23fee9755734512d125c

Limit Rotation: add an Euler Order option and orthogonalize the matrix.

Since Limit Rotation is based on Euler decomposition, it should allow
specifying the order to use for the same reasons as Copy Rotation does,
namely, if the bone uses Quaternion rotation for its animation channels,
there is no way to choose the order for the constraint.

In addition, add a call to orthogonalize the matrix before processing
for the same reasons as D8915, and an early exit in case no limits are
enabled for a bit of extra efficiency.

Since the constraint goes through Euler decomposition, it would remove
shear even before the change, but the rotation won't make much sense.

Differential Revision: https://developer.blender.org/D9626

===================================================================

M	release/scripts/startup/bl_ui/properties_constraint.py
M	source/blender/blenkernel/intern/constraint.c
M	source/blender/makesdna/DNA_constraint_types.h
M	source/blender/makesrna/intern/rna_constraint.c

===================================================================

diff --git a/release/scripts/startup/bl_ui/properties_constraint.py b/release/scripts/startup/bl_ui/properties_constraint.py
index 71a7b056d07..a7ac96508f4 100644
--- a/release/scripts/startup/bl_ui/properties_constraint.py
+++ b/release/scripts/startup/bl_ui/properties_constraint.py
@@ -245,6 +245,7 @@ class ConstraintButtonsPanel(Panel):
         sub.prop(con, "max_z", text="Max")
         row.label(icon="BLANK1")
 
+        layout.prop(con, "euler_order", text="Order")
         layout.prop(con, "use_transform_limit")
         self.space_template(layout, con, target=False, owner=True)
 
diff --git a/source/blender/blenkernel/intern/constraint.c b/source/blender/blenkernel/intern/constraint.c
index 9b3c6e3c955..5bd8a2bc576 100644
--- a/source/blender/blenkernel/intern/constraint.c
+++ b/source/blender/blenkernel/intern/constraint.c
@@ -1647,10 +1647,28 @@ static void rotlimit_evaluate(bConstraint *con, bConstraintOb *cob, ListBase *UN
   float eul[3];
   float size[3];
 
+  /* This constraint is based on euler rotation math, which doesn't work well with shear.
+   * The Y axis is chosen as the main one because constraints are most commonly used on bones.
+   * This also allows using the constraint to simply remove shear. */
+  orthogonalize_m4_stable(cob->matrix, 1, false);
+
+  /* Only do the complex processing if some limits are actually enabled. */
+  if (!(data->flag & (LIMIT_XROT | LIMIT_YROT | LIMIT_ZROT))) {
+    return;
+  }
+
+  /* Select the Euler rotation order, defaulting to the owner value. */
+  short rot_order = cob->rotOrder;
+
+  if (data->euler_order != CONSTRAINT_EULER_AUTO) {
+    rot_order = data->euler_order;
+  }
+
+  /* Decompose the matrix using the specified order. */
   copy_v3_v3(loc, cob->matrix[3]);
   mat4_to_size(size, cob->matrix);
 
-  mat4_to_eulO(eul, cob->rotOrder, cob->matrix);
+  mat4_to_eulO(eul, rot_order, cob->matrix);
 
   /* constraint data uses radians internally */
 
@@ -1683,7 +1701,7 @@ static void rotlimit_evaluate(bConstraint *con, bConstraintOb *cob, ListBase *UN
     }
   }
 
-  loc_eulO_size_to_mat4(cob->matrix, loc, eul, size, cob->rotOrder);
+  loc_eulO_size_to_mat4(cob->matrix, loc, eul, size, rot_order);
 }
 
 static bConstraintTypeInfo CTI_ROTLIMIT = {
diff --git a/source/blender/makesdna/DNA_constraint_types.h b/source/blender/makesdna/DNA_constraint_types.h
index d3f0809204b..20b60a52077 100644
--- a/source/blender/makesdna/DNA_constraint_types.h
+++ b/source/blender/makesdna/DNA_constraint_types.h
@@ -536,6 +536,8 @@ typedef struct bRotLimitConstraint {
   float zmin, zmax;
   short flag;
   short flag2;
+  char euler_order;
+  char _pad[3];
 } bRotLimitConstraint;
 
 /* Limit Scale Constraint */
diff --git a/source/blender/makesrna/intern/rna_constraint.c b/source/blender/makesrna/intern/rna_constraint.c
index 343318726c7..eeed8d2f9b3 100644
--- a/source/blender/makesrna/intern/rna_constraint.c
+++ b/source/blender/makesrna/intern/rna_constraint.c
@@ -2602,6 +2602,12 @@ static void rna_def_constraint_rotation_limit(BlenderRNA *brna)
   RNA_def_property_ui_text(prop, "Maximum Z", "Highest Z value to allow");
   RNA_def_property_update(prop, NC_OBJECT | ND_CONSTRAINT, "rna_Constraint_update");
 
+  prop = RNA_def_property(srna, "euler_order", PROP_ENUM, PROP_NONE);
+  RNA_def_property_enum_sdna(prop, NULL, "euler_order");
+  RNA_def_property_enum_items(prop, euler_order_items);
+  RNA_def_property_ui_text(prop, "Euler Order", "Explicitly specify the euler rotation order");
+  RNA_def_property_update(prop, NC_OBJECT | ND_CONSTRAINT, "rna_Constraint_update");
+
   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(