1. MPI_Allgatherv, version 0.6.2

2. add test worlds and for single machine two Gazebo
3. add openmpi version in world.cc

Gazebo_Distributed_MPI/gazebo/CMakeLists.txt

@@ -1,4 +1,6 @@
-find_package(MPI REQUIRED)  # Added by zhangshuai 2019.04.22 for MPI
+#find_package(MPI REQUIRED)  # Added by zhangshuai 2019.04.22 for MPI
+
+message(STATUS "++++++++++ Using MPI_INCLUDE_PATH: ${MPI_INCLUDE_PATH} ++++++++++") # Added by zhangshuai 2019.04.22 for MPI
 
 include_directories(SYSTEM
   ${OPENGL_INCLUDE_DIR}

Gazebo_Distributed_MPI/gazebo/physics/World.cc

@@ -297,11 +297,16 @@ void World::Load(sdf::ElementPtr _sdf)
   {
     sdf::ElementPtr distributionElem = this->dataPtr->sdf->GetElement("distribution");
     char proc_name[MPI_MAX_PROCESSOR_NAME];
+    char version[MPI_MAX_LIBRARY_VERSION_STRING];
     int nameLength;
+    int versionLength;
     MPI_Comm_rank(MPI_COMM_WORLD, &this->gazeboLocalID);
     MPI_Comm_size(MPI_COMM_WORLD, &this->nproc);
     MPI_Get_processor_name(proc_name, &nameLength);
-    printf("Gazebo, Iam host %s with rank %d of %d\n", proc_name, this->gazeboLocalID, this->nproc);
+    MPI_Get_library_version(version, &versionLength);
+    // printf("Gazebo, I am host %s with rank %d of %d\n", proc_name, this->gazeboLocalID, this->nproc);
+    std::cout << "Gazebo!  I am host " << proc_name << " with rank " << this->gazeboLocalID << " of " << this->nproc
+              << "(" << version << ", " << versionLength << ")" << std::endl;
 
     this->flag = distributionElem->Get<int>("flag");
 
@@ -988,6 +993,8 @@ void World::Update()
 #endif
     // Added by zhangshuai 2019.04.03 for count time ----End
 
+    MPI_Barrier(MPI_COMM_WORLD);
+
     // Added by zhangshuai 2019.04.03 for count time ----Begin
 #ifdef USE_COUNT_TIME
     gettimeofday(&tv, NULL);
@@ -996,7 +1003,7 @@ void World::Update()
     // Added by zhangshuai 2019.04.03 for count time ----End
 
     MPI_Allgatherv(sendBuffer, this->sendBufferLen, MPI_CHAR, receiveBuffer, tmpbufferLen, tmpdispls, MPI_CHAR, MPI_COMM_WORLD);
-    MPI_Barrier(MPI_COMM_WORLD);
+    // MPI_Barrier(MPI_COMM_WORLD);
 
     // Added by zhangshuai 2019.04.03 for count time ----Begin
 #ifdef USE_COUNT_TIME

Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_description/urdf/generic_camera.urdf.xacro

@@ -12,7 +12,7 @@
     </joint>
     
     <link name="${name}_link">
-<!--      <inertial>
+      <!--<inertial>
         <mass value="0.001" />
         <origin xyz="0 0 0" rpy="0 0 0" />
         <inertia ixx="0.0001" ixy="0" ixz="0" iyy="0.0001" iyz="0" izz="0.0001" />
@@ -43,7 +43,7 @@
     <link name="${name}_optical_frame"/>
     
     <gazebo reference="${name}_link">
-      <!--<sensor type="camera" name="${name}_camera_sensor">
+      <!-- <sensor type="camera" name="${name}_camera_sensor">
         <update_rate>${update_rate}</update_rate>
         <camera>
           <horizontal_fov>${hfov * M_PI/180.0}</horizontal_fov>
@@ -64,8 +64,8 @@
           <cameraInfoTopicName>${cam_info_topic}</cameraInfoTopicName>
           <frameName>${name}_optical_frame</frameName>
         </plugin>
-      </sensor>-->
-      <sensor name='back_left_far_sonar_sensor' type='ray'>
+      </sensor> -->
+      <!--<sensor name='back_left_far_sonar_sensor' type='ray'>
         <ray>
           <scan>
             <horizontal>
@@ -89,7 +89,7 @@
         <always_on>0</always_on>
         <update_rate>5</update_rate>
         <pose frame=''>0.7 2.4 0.5 0 -0 1.5707</pose>
-      </sensor>
+      </sensor>-->
     </gazebo>
   </xacro:macro>