First step towards a MuJoCo MJCF importer for Bullet. It can load the humanoid.xml, ant.xml and some other OpenAI GYM asset files. Not all fields are converted, so it is work-in-progress. This is useful for Reinforcement Learning experiments, and would also help integration with DeepMind Lab.

2016-12-30 18:32:57 -08:00
parent 7b9d194bfd
commit fdd517e00f
16 changed files with 1713 additions and 21 deletions
--- a/examples/Importers/ImportMJCFDemo/BulletMJCFImporter.h
+++ b/examples/Importers/ImportMJCFDemo/BulletMJCFImporter.h
@@ -0,0 +1,78 @@
+#ifndef BULLET_MJCF_IMPORTER_H
+#define BULLET_MJCF_IMPORTER_H
+
+#include "../ImportURDFDemo/URDFImporterInterface.h"
+#include "../ImportURDFDemo/LinkVisualShapesConverter.h"
+
+
+struct MJCFErrorLogger
+{
+	virtual void reportError(const char* error)=0;
+	virtual void reportWarning(const char* warning)=0;
+	virtual void printMessage(const char* msg)=0;
+};
+
+
+
+class BulletMJCFImporter : public URDFImporterInterface
+{
+	struct BulletMJCFImporterInternalData* m_data;
+
+
+public:
+	BulletMJCFImporter(struct GUIHelperInterface* helper);
+	virtual ~BulletMJCFImporter();
+	
+	virtual bool parseMJCFString(const char* xmlString, MJCFErrorLogger* logger);
+
+	virtual bool loadMJCF(const char* fileName, MJCFErrorLogger* logger, bool forceFixedBase = false);
+
+	int getNumModels() const;
+
+	void activateModel(int modelIndex);
+
+	virtual bool loadURDF(const char* fileName, bool forceFixedBase = false)
+	{
+		return false;
+	}
+
+    virtual bool loadSDF(const char* fileName, bool forceFixedBase = false) { return false;}
+
+    virtual const char* getPathPrefix();
+    
+    ///return >=0 for the root link index, -1 if there is no root link
+    virtual int getRootLinkIndex() const;
+    
+    ///pure virtual interfaces, precondition is a valid linkIndex (you can assert/terminate if the linkIndex is out of range)
+    virtual std::string getLinkName(int linkIndex) const;
+
+	/// optional method to provide the link color. return true if the color is available and copied into colorRGBA, return false otherwise
+	virtual bool getLinkColor(int linkIndex, btVector4& colorRGBA) const;
+
+	///this API will likely change, don't override it!
+	virtual bool getLinkContactInfo(int linkIndex, URDFLinkContactInfo& contactInfo ) const;
+    
+    virtual std::string getJointName(int linkIndex) const;
+
+    //fill mass and inertial data. If inertial data is missing, please initialize mass, inertia to sensitive values, and inertialFrame to identity.
+    virtual void  getMassAndInertia(int urdfLinkIndex, btScalar& mass,btVector3& localInertiaDiagonal, btTransform& inertialFrame) const;
+    
+    ///fill an array of child link indices for this link, btAlignedObjectArray behaves like a std::vector so just use push_back and resize(0) if needed
+    virtual void getLinkChildIndices(int urdfLinkIndex, btAlignedObjectArray<int>& childLinkIndices) const;
+    
+    virtual bool getJointInfo(int urdfLinkIndex, btTransform& parent2joint, btTransform& linkTransformInWorld, btVector3& jointAxisInJointSpace, int& jointType, btScalar& jointLowerLimit, btScalar& jointUpperLimit, btScalar& jointDamping, btScalar& jointFriction) const;
+    
+    virtual bool getRootTransformInWorld(btTransform& rootTransformInWorld) const;
+    
+	virtual int convertLinkVisualShapes(int linkIndex, const char* pathPrefix, const btTransform& inertialFrame) const;
+    
+    virtual void convertLinkVisualShapes2(int linkIndex, const char* pathPrefix, const btTransform& inertialFrame, class btCollisionObject* colObj, int objectIndex) const;
+    virtual void setBodyUniqueId(int bodyId);
+    virtual int getBodyUniqueId() const;
+    
+	virtual class btCompoundShape* convertLinkCollisionShapes(int linkIndex, const char* pathPrefix, const btTransform& localInertiaFrame) const ;
+
+
+};
+
+#endif //BULLET_MJCF_IMPORTER_H