Added gizmos for the constraint pivot

Added text describing how to use each constraint
Renamed the constraint axis

UnityProject/Assets/BulletUnity/Scripts/Constraints/B6DOFConstraint.cs

@@ -10,11 +10,12 @@ public class B6DOFConstraint : BTypedConstraint {
         //Todo not sure if this is working
         //Todo breaking strength
         //todo should be properties so can capture changes and propagate to scene
+        public static string HelpMessage = "\n" +
+                                            "\nTIP: To see constraint limits:\n" +
+                                            "  - In BulletPhysicsWorld turn on 'Do Debug Draw' and set 'Debug Draw Mode' flags\n" +
+                                            "  - On Constraint set 'Debug Draw Size'\n" +
+                                            "  - Press play";
 
-        [Header("Reference Frame Local To This Object")]
-        public Vector3 m_localConstraintPoint = Vector3.zero;
-        public Vector3 m_localConstraintForwardDir = Vector3.forward;
-        public Vector3 m_localConstraintUpDir = Vector3.up;
 
         [Header("Limits")]
         public Vector3 m_linearLimitLower;
@@ -72,7 +73,7 @@ internal override bool _BuildConstraint() {
 
                 BM.Matrix frameInA, frameInOther;
                 string errormsg = "";
-                if (CreateFramesA_B(m_localConstraintForwardDir, m_localConstraintUpDir, m_localConstraintPoint, out frameInA, out frameInOther, ref errormsg))
+                if (CreateFramesA_B(m_localConstraintAxisX, m_localConstraintAxisY, m_localConstraintPoint, out frameInA, out frameInOther, ref errormsg))
                 {
                     m_constraintPtr = new Generic6DofConstraint(rbb, rba, frameInOther, frameInA, true);
                 } else

UnityProject/Assets/BulletUnity/Scripts/Constraints/BBallSocketConstraint.cs

@@ -10,9 +10,11 @@ public class BBallSocketConstraint : BTypedConstraint {
 
 
         //todo should be properties so can capture changes and propagate to scene
-
-        [Header("Constraint Point Local To This Object")]
-        public Vector3 m_localConstraintPoint = Vector3.zero;
+        public static string HelpMessage =  "Only the 'Local Constraint Point' is used. X and Y are ignored.\n" +
+                                            "\nTIP: To see constraint limits:\n" +
+                                            "  - In BulletPhysicsWorld turn on 'Do Debug Draw' and set 'Debug Draw Mode' flags\n" +
+                                            "  - On Constraint set 'Debug Draw Size'\n" +
+                                            "  - Press play";
 
         //called by Physics World just before constraint is added to world.
         //the current constraint properties are used to rebuild the constraint.

UnityProject/Assets/BulletUnity/Scripts/Constraints/BConeTwistConstraint.cs

@@ -5,7 +5,6 @@
 using BM = BulletSharp.Math;
 
 namespace BulletUnity {
-    //TODO script execution order, rigid bodies before constraints & other stuff that might use them
     [System.Serializable]
     public class BConeTwistConstraint : BTypedConstraint {
         public static string HelpMessage = "btConeTwistConstraint can be used to simulate ragdoll joints (upper arm, leg etc)." +
@@ -14,14 +13,14 @@ public class BConeTwistConstraint : BTypedConstraint {
                                             "Swing is divided into swing1 and swing2 which can have different limits, giving an elliptical shape."+
                                             "(Note: the cone's base isn't flat, so this ellipse is 'embedded' on the surface of a sphere.)\n\n"+
                                             "In the contraint's frame of reference:\n"+
-                                            "  - twist is along the forward\n"+
-                                            "  - and swing 1 and 2 are along the right and up axes respectively.\n";
+                                            "  - twist is along the X (blue) twist limit is about Y (green) \n"+
+                                            "  - and swing 1 and 2 are along the Y (green) and Z (red) axes respectively.\n" +
+                                            "\nTIP: To see constraint limits:\n" + 
+                                            "  - In BulletPhysicsWorld turn on 'Do Debug Draw' and set 'Debug Draw Mode' flags\n" +
+                                            "  - On Constraint set 'Debug Draw Size'\n" +
+                                            "  - Press play";
 
 
-        [Header("Reference Frame Local To This Object")]
-        public Vector3 m_localConstraintPoint = Vector3.zero;
-        public Vector3 m_localConstraintForwardDir = Vector3.forward;
-        public Vector3 m_localConstraintUpDir = Vector3.up;
 
         [Header("Limits")]
         public float m_swingSpan1Radians = Mathf.PI;
@@ -66,7 +65,7 @@ internal override bool _BuildConstraint() {
                 }
                 BM.Matrix frameInA, frameInOther;
                 string errormsg = "";
-                if (CreateFramesA_B(m_localConstraintForwardDir, m_localConstraintUpDir, m_localConstraintPoint, out frameInA, out frameInOther, ref errormsg))
+                if (CreateFramesA_B(m_localConstraintAxisX, m_localConstraintAxisY, m_localConstraintPoint, out frameInA, out frameInOther, ref errormsg))
                 {
                     m_constraintPtr = new ConeTwistConstraint((RigidBody)m_otherRigidBody.GetCollisionObject(), (RigidBody)targetRigidBodyA.GetCollisionObject(), frameInOther, frameInA);
                 } else
@@ -81,7 +80,7 @@ internal override bool _BuildConstraint() {
                 //TODO this is broken
                 string errormsg = "";
                 BM.Matrix frameInB = BM.Matrix.Identity;
-                if (CreateFrame(m_localConstraintForwardDir, m_localConstraintUpDir, m_localConstraintPoint, ref frameInB, ref errormsg))
+                if (CreateFrame(m_localConstraintAxisX, m_localConstraintAxisY, m_localConstraintPoint, ref frameInB, ref errormsg))
                 {
                     m_constraintPtr = new ConeTwistConstraint((RigidBody)targetRigidBodyA.GetCollisionObject(), frameInB);
                 } else

UnityProject/Assets/BulletUnity/Scripts/Constraints/BFixedConstraint.cs

@@ -9,10 +9,6 @@ namespace BulletUnity {
     public class BFixedConstraint : BTypedConstraint {
 
         //todo should be properties so can capture changes and propagate to scene
-        [Header("Reference Frame Local To This Object")]
-        public Vector3 m_localConstraintPoint = Vector3.zero;
-        public Vector3 m_localConstraintForwardDir = Vector3.forward;
-        public Vector3 m_localConstraintUpDir = Vector3.up;
 
         //called by Physics World just before constraint is added to world.
         //the current constraint properties are used to rebuild the constraint.
@@ -62,7 +58,7 @@ internal override bool _BuildConstraint() {
             }
             BM.Matrix frameInA, frameInOther;
             string errormsg = "";
-            if (CreateFramesA_B(m_localConstraintForwardDir, m_localConstraintUpDir, m_localConstraintPoint, out frameInA, out frameInOther, ref errormsg))
+            if (CreateFramesA_B(m_localConstraintAxisX, m_localConstraintAxisY, m_localConstraintPoint, out frameInA, out frameInOther, ref errormsg))
             {
                 m_constraintPtr = new FixedConstraint(rbb, rba, frameInOther, frameInA);
             } else

UnityProject/Assets/BulletUnity/Scripts/Constraints/BHingedConstraint.cs

@@ -9,13 +9,11 @@ namespace BulletUnity {
     public class BHingedConstraint : BTypedConstraint {
 
         //todo should be properties so can capture changes and propagate to scene
-        /// <summary>
-        /// In targetRigidbody local coordinates
-        /// </summary>
-        [Header("Reference Frame Local To This Object")]
-        public Vector3 m_localConstraintPoint = Vector3.zero;
-        public Vector3 m_localConstraintForwardDir = Vector3.forward;
-        public Vector3 m_localConstraintUpDir = Vector3.up;
+        public static string HelpMessage = "X (red) is axis of the hinge.\n" +
+                                            "\nTIP: To see constraint limits:\n" +
+                                            "  - In BulletPhysicsWorld turn on 'Do Debug Draw' and set 'Debug Draw Mode' flags\n" +
+                                            "  - On Constraint set 'Debug Draw Size'\n" +
+                                            "  - Press play";
 
         public bool m_enableMotor;
         public float m_targetMotorAngularVelocity = 0f;
@@ -54,7 +52,7 @@ internal override bool _BuildConstraint() {
             {
                 world.AddRigidBody(targetRigidBodyA);
             }
-            if (m_localConstraintForwardDir == Vector3.zero)
+            if (m_localConstraintAxisX == Vector3.zero)
             {
                 Debug.LogError("Constaint axis cannot be zero vector");
                 return false;
@@ -83,7 +81,7 @@ internal override bool _BuildConstraint() {
                 }
                 BM.Matrix frameInA, frameInOther;
                 string errormsg = "";
-                if (CreateFramesA_B(m_localConstraintForwardDir, m_localConstraintUpDir, m_localConstraintPoint, out frameInA, out frameInOther, ref errormsg))
+                if (CreateFramesA_B(m_localConstraintAxisX, m_localConstraintAxisY, m_localConstraintPoint, out frameInA, out frameInOther, ref errormsg))
                 {
                     //warning the frameInA, frameInB version of the constructor is broken
                     m_constraintPtr = new HingeConstraint(rbb, rba, frameInOther.Origin, frameInA.Origin, (BM.Vector3)frameInOther.Basis.Column1, (BM.Vector3)frameInA.Basis.Column1);
@@ -96,7 +94,7 @@ internal override bool _BuildConstraint() {
             else {
                 //BM.Matrix frameInA = BM.Matrix.Identity;
                 //CreateFrame(m_localConstraintForwardDir, m_localConstraintUpDir, m_localConstraintPoint, ref frameInA);
-                m_constraintPtr = new HingeConstraint(rba, m_localConstraintPoint.ToBullet(),m_localConstraintForwardDir.ToBullet(), false);
+                m_constraintPtr = new HingeConstraint(rba, m_localConstraintPoint.ToBullet(),m_localConstraintAxisX.ToBullet(), false);
             }
             if (m_enableMotor)
             {

UnityProject/Assets/BulletUnity/Scripts/Constraints/BSliderConstraint.cs

@@ -7,23 +7,18 @@
 namespace BulletUnity {
     [System.Serializable]
     public class BSliderConstraint : BTypedConstraint {
-
-        [Header("Reference Frame Local To This Object")]
-        public Vector3 m_localConstraintPoint = Vector3.zero;
-        public Vector3 m_localConstraintForwardDir = Vector3.forward;
-        public Vector3 m_localConstraintUpDir = Vector3.up;
+        public static string HelpMessage = "X (red) is slide axis. Angular limits are measured from Y (green) toward Z. \n" +
+                                            "\nTIP: To see constraint limits:\n" +
+                                            "  - In BulletPhysicsWorld turn on 'Do Debug Draw' and set 'Debug Draw Mode' flags\n" +
+                                            "  - On Constraint set 'Debug Draw Size'\n" +
+                                            "  - Press play";
 
         [Header("Limits")]
         public float m_lowerLinearLimit = -10f;
         public float m_upperLinearLimit = 10f;
         public float m_lowerAngularLimitRadians = -Mathf.PI;
         public float m_upperAngularLimitRadians = Mathf.PI;
 
-        public void OnDrawGizmosSelected()
-        {
-            DrawTransformGizmos(transform, m_localConstraintPoint, m_localConstraintForwardDir, m_localConstraintUpDir);
-        }
-
         //called by Physics World just before constraint is added to world.
         //the current constraint properties are used to rebuild the constraint.
         internal override bool _BuildConstraint() {
@@ -69,7 +64,7 @@ internal override bool _BuildConstraint() {
 
                 BM.Matrix frameInA, frameInOther;
                 string errormsg = "";
-                if (CreateFramesA_B(m_localConstraintForwardDir, m_localConstraintUpDir, m_localConstraintPoint, out frameInA, out frameInOther, ref errormsg))
+                if (CreateFramesA_B(m_localConstraintAxisX, m_localConstraintAxisY, m_localConstraintPoint, out frameInA, out frameInOther, ref errormsg))
                 {
                     m_constraintPtr = new SliderConstraint(rbb, rba, frameInOther, frameInA, true);
                 } else
@@ -81,7 +76,7 @@ internal override bool _BuildConstraint() {
             {
                 BulletSharp.Math.Matrix frameInA = BM.Matrix.Identity;
                 string errormsg = "";
-                if (CreateFrame(m_localConstraintForwardDir, m_localConstraintUpDir, m_localConstraintPoint, ref frameInA, ref errormsg))
+                if (CreateFrame(m_localConstraintAxisX, m_localConstraintAxisY, m_localConstraintPoint, ref frameInA, ref errormsg))
                 {
                     m_constraintPtr = new SliderConstraint(rba, frameInA, true);
                 } else

UnityProject/Assets/BulletUnity/Scripts/Constraints/BTypedConstraint.cs

@@ -16,6 +16,13 @@ public enum ConstraintType
             constrainToAnotherBody
         }
 
+        [Header("Reference Frame Local To This Object")]
+        public Vector3 m_localConstraintPoint = Vector3.zero;
+        public Vector3 m_localConstraintAxisX = Vector3.forward;
+        public Vector3 m_localConstraintAxisY = Vector3.up;
+
+
+
         public float m_breakingImpulseThreshold = Mathf.Infinity;
         public bool m_disableCollisionsBetweenConstrainedBodies = true;
         public ConstraintType m_constraintType;
@@ -30,18 +37,18 @@ public enum ConstraintType
         public void DrawTransformGizmos(Transform t, Vector3 pivotPoint, Vector3 forward, Vector3 up)
         {
             Vector3 pivotWorld = t.TransformPoint(pivotPoint);
-            Vector3 forwardWorld = t.TransformDirection(forward).normalized;
-            Vector3 upWorld = t.TransformDirection(up).normalized;
-            Vector3 rightWorld = Vector3.Cross(forwardWorld, upWorld);
-            upWorld = Vector3.Cross(rightWorld, forwardWorld);
-            upWorld.Normalize();
-            forwardWorld.Normalize();
+            Vector3 xWorld = t.TransformDirection(forward).normalized;
+            Vector3 yWorld = t.TransformDirection(up).normalized;
+            Vector3 zWorld = Vector3.Cross(xWorld, yWorld);
+            yWorld = Vector3.Cross(zWorld, xWorld);
+            yWorld.Normalize();
+            xWorld.Normalize();
             Gizmos.color = Color.red;
-            Gizmos.DrawLine(pivotWorld, pivotWorld + rightWorld);
+            Gizmos.DrawLine(pivotWorld, pivotWorld + xWorld);
             Gizmos.color = Color.green;
-            Gizmos.DrawLine(pivotWorld, pivotWorld + upWorld);
+            Gizmos.DrawLine(pivotWorld, pivotWorld + yWorld);
             Gizmos.color = Color.blue;
-            Gizmos.DrawLine(pivotWorld, pivotWorld + forwardWorld);
+            Gizmos.DrawLine(pivotWorld, pivotWorld + zWorld);
         }
 
         public bool CreateFrame(UnityEngine.Vector3 forward, UnityEngine.Vector3 up, UnityEngine.Vector3 constraintPoint, ref BulletSharp.Math.Matrix m, ref string errorMsg)
@@ -109,6 +116,13 @@ public bool CreateFramesA_B(UnityEngine.Vector3 forwardInA, UnityEngine.Vector3
             return true;
         }
 
+        public virtual void OnDrawGizmosSelected()
+        {
+            DrawTransformGizmos(transform, m_localConstraintPoint, m_localConstraintAxisX, m_localConstraintAxisY);
+        }
+
+
+
         protected virtual void AddToBulletWorld()
         {
             if (!m_isInWorld)

UnityProject/Assets/BulletUnity/Scripts/Constraints/Editor/B6DOFConstraintEditor.cs

@@ -0,0 +1,14 @@
+using UnityEditor;
+using UnityEngine;
+using BulletUnity;
+
+[CustomEditor(typeof(B6DOFConstraint))]
+public class B6DOFConstraintEditor : Editor {
+
+
+
+    public override void OnInspectorGUI() {
+        EditorGUILayout.HelpBox(B6DOFConstraint.HelpMessage, MessageType.Info);
+        DrawDefaultInspector();
+    }
+}

UnityProject/Assets/BulletUnity/Scripts/Constraints/Editor/BBallSocketConstraintEditor.cs

@@ -0,0 +1,14 @@
+using UnityEditor;
+using UnityEngine;
+using BulletUnity;
+
+[CustomEditor(typeof(BBallSocketConstraint))]
+public class BBallSocketConstraintEditor : Editor {
+
+
+
+    public override void OnInspectorGUI() {
+        EditorGUILayout.HelpBox(BBallSocketConstraint.HelpMessage, MessageType.Info);
+        DrawDefaultInspector();
+    }
+}

UnityProject/Assets/BulletUnity/Scripts/Constraints/Editor/BHingedConstraintEditor.cs

@@ -9,6 +9,7 @@ public class BHingedConstraintEditor : Editor {
 
     public override void OnInspectorGUI() {
         BHingedConstraint hc = (BHingedConstraint)target;
+        EditorGUILayout.HelpBox(BHingedConstraint.HelpMessage, MessageType.Info);
         EditorGUILayout.LabelField("Hinge Angle " + hc.GetAngle());
         DrawDefaultInspector();
     }

UnityProject/Assets/BulletUnity/Scripts/Constraints/Editor/BSliderConstraintEditor.cs

@@ -0,0 +1,15 @@
+using UnityEditor;
+using UnityEngine;
+using BulletUnity;
+
+[CustomEditor(typeof(BSliderConstraint))]
+public class BSliderConstraintEditor : Editor {
+
+
+
+    public override void OnInspectorGUI() {
+        BSliderConstraint hc = (BSliderConstraint)target;
+        EditorGUILayout.HelpBox(BSliderConstraint.HelpMessage, MessageType.Info);
+        DrawDefaultInspector();
+    }
+}