Initial release of the Unity plugin.

PiperOrigin-RevId: 425947505
2022-02-02 20:17:13 +00:00
parent 8ec3dd97a4
commit 6de9eafa13
298 changed files with 20617 additions and 2 deletions
@@ -0,0 +1,171 @@
+// Copyright 2019 DeepMind Technologies Limited
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+using System;
+using System.Xml;
+using UnityEngine;
+
+namespace Mujoco {
+
+  [Serializable]
+  public struct MjJointSettings {
+    [Tooltip("Added inertia of all DoFs created by this joint.")]
+    public float Armature;
+
+    [Tooltip("Joint spring settings.")]
+    public SpringSettings Spring;
+
+    [Tooltip("Joint solver settings.")]
+    public SolverSettings Solver;
+
+    // Default joint settings.
+    public static MjJointSettings Default = new MjJointSettings() {
+      Solver = SolverSettings.Default,
+    };
+
+    public void FromMjcf(XmlElement mjcf) {
+      Armature = mjcf.GetFloatAttribute("armature", 0.0f);
+      Spring.FromMjcf(mjcf);
+      Solver.FromMjcf(mjcf);
+    }
+
+    public void ToMjcf(XmlElement mjcf) {
+      mjcf.SetAttribute("armature", $"{Armature}");
+      Spring.ToMjcf(mjcf);
+      Solver.ToMjcf(mjcf);
+    }
+  }
+
+  [Serializable]
+  public struct SpringSettings {
+    public float TimeConstant;
+    public float DampingRatio;
+
+    [Tooltip("Joint stiffness. If this value is positive, a spring will be created.")]
+    public float Stiffness;
+    [Tooltip("Damping applied to all degrees of freedom created by this joint.")]
+    public float Damping;
+
+    [Tooltip("Spring equilibrium pose.")]
+    public float EquilibriumPose;
+
+    public void ToMjcf(XmlElement mjcf) {
+      // Spring settings.
+      mjcf.SetAttribute("springref", $"{EquilibriumPose}");
+      mjcf.SetAttribute("springdamper", $"{TimeConstant} {DampingRatio}");
+      mjcf.SetAttribute("damping", $"{Damping}");
+      mjcf.SetAttribute("stiffness", $"{Stiffness}");
+    }
+
+    public void FromMjcf(XmlElement mjcf) {
+      var springDamper = mjcf.GetVector2Attribute("springdamper", Vector2.zero);
+      TimeConstant = springDamper.x;
+      DampingRatio = springDamper.y;
+      EquilibriumPose = mjcf.GetFloatAttribute("springref", 0.0f);
+      Damping = mjcf.GetFloatAttribute("damping", 0.0f);
+      Stiffness = mjcf.GetFloatAttribute("stiffness", 0.0f);
+    }
+  }
+
+  [Serializable]
+  public struct SolverImpedance {
+    public float DMin;
+    public float DMax;
+    public float Width;
+    public float Midpoint;
+    public float Power;
+
+    public static SolverImpedance Default =
+        new SolverImpedance() { DMin = 0.9f, DMax = 0.95f, Width = 0.001f, Midpoint = 0.5f,
+                                Power = 2.0f };
+
+    public void FromMjcf(XmlElement element, string attributeName) {
+      var values = element.GetFloatArrayAttribute(
+          attributeName, new float[] { Default.DMin, Default.DMax, Default.Width, Default.Midpoint,
+                                       Default.Power });
+      DMin = values[0];
+      DMax = values[1];
+      Width = values[2];
+      Midpoint = values[3];
+      Power = values[4];
+    }
+
+    public void ToMjcf(XmlElement element, string attributeName) {
+      element.SetAttribute(attributeName, $"{DMin} {DMax} {Width} {Midpoint} {Power}");
+    }
+  }
+
+  [Serializable]
+  public struct SolverReference {
+    public float TimeConst;
+    public float DampRatio;
+
+    public static SolverReference Default =
+        new SolverReference() { TimeConst = 0.02f, DampRatio = 1.0f };
+
+    public void FromMjcf(XmlElement element, string attributeName) {
+      var values = element.GetFloatArrayAttribute(
+          attributeName, new float[] { Default.TimeConst, Default.DampRatio });
+      TimeConst = values[0];
+      DampRatio = values[1];
+    }
+
+    public void ToMjcf(XmlElement element, string attributeName) {
+      element.SetAttribute(attributeName, $"{TimeConst} {DampRatio}");
+    }
+  }
+
+  [Serializable]
+  public struct SolverSettings {
+    [Tooltip("Does the joint have limits.")]
+    public bool Limited;
+
+    [Tooltip("Limit margin - always in radians/meters.")]
+    public float Margin;
+    public SolverReference RefLimit;
+    public SolverImpedance ImpLimit;
+
+    [Tooltip("Friction loss due to dry friction.")]
+    public float FrictionLoss;
+    public SolverImpedance ImpFriction;
+    public SolverReference RefFriction;
+
+    public static SolverSettings Default = new SolverSettings() {
+      ImpFriction = SolverImpedance.Default,
+      ImpLimit = SolverImpedance.Default,
+      RefFriction = SolverReference.Default,
+      RefLimit = SolverReference.Default,
+    };
+
+    public void ToMjcf(XmlElement mjcf) {
+      RefLimit.ToMjcf(mjcf, "solreflimit");
+      ImpLimit.ToMjcf(mjcf, "solimplimit");
+      RefFriction.ToMjcf(mjcf, "solreffriction");
+      ImpFriction.ToMjcf(mjcf, "solimpfriction");
+      mjcf.SetAttribute("frictionloss", $"{FrictionLoss}");
+      mjcf.SetAttribute("limited", $"{Limited}".ToLower());
+      mjcf.SetAttribute("margin", $"{Margin}");
+    }
+
+    public void FromMjcf(XmlElement mjcf) {
+      RefLimit.FromMjcf(mjcf, "solreflimit");
+      ImpLimit.FromMjcf(mjcf, "solimplimit");
+      RefFriction.FromMjcf(mjcf, "solreffriction");
+      ImpFriction.FromMjcf(mjcf, "solimpfriction");
+      FrictionLoss = mjcf.GetFloatAttribute("frictionloss", 0.0f);
+      Limited = mjcf.GetBoolAttribute("limited", false);
+      Margin = mjcf.GetFloatAttribute("margin", defaultValue: 0.0f);
+    }
+  }
+}