add hh rew

Project/Assets/ML-Agents/Examples/Walker/Scripts/WalkerAgent.cs

         //This reward will approach 1 if it faces the target direction perfectly and approach zero as it deviates
         var lookAtTargetReward = (Vector3.Dot(cubeForward, head.forward) + 1) * .5F;
         // c. Encourage head height.
-//        headHeightOverFeetReward =
-//            Mathf.Clamp01(((head.position.y - footL.position.y) + (head.position.y - footR.position.y))/ 10); //Should normalize to ~1
+        var headHeightOverFeetReward =
+            Mathf.Clamp01(((head.position.y - footL.position.y) + (head.position.y - footR.position.y))/ 10); //Should normalize to ~1
-//        rewardManager.rewardsDict["headHeightOverFeet"].rewardThisStep = headHeightOverFeetReward;
-        rewardManager.UpdateReward("productOfAllRewards", matchSpeedReward * lookAtTargetReward);
+        rewardManager.rewardsDict["headHeightOverFeet"].rewardThisStep = headHeightOverFeetReward;
+        rewardManager.UpdateReward("productOfAllRewards", matchSpeedReward * lookAtTargetReward * headHeightOverFeetReward);
+//        rewardManager.UpdateReward("productOfAllRewards", matchSpeedReward * lookAtTargetReward);
     }
 
     //Returns the average velocity of all the rigidbodies