correct viewpoint past visualization

MBsysC/mbs_common/mbs_realtime/java/java_functions.c

@@ -193,11 +193,26 @@ void update_java(Simu_realtime *realtime)
 
     if (java->visu_past_flag)
     {
-        java->visu_past_flag = 0;
+        java->visu_past_flag   = 0;
+        java->last_past_q_flag = 1;
+
         update_jni(java->jni_struct, java, java->nb_q, java->past_q);
     }
+    else if (java->change_viewpoint)
+    {
+        if (java->last_past_q_flag)
+        {
+            update_jni(java->jni_struct, java, java->nb_q, java->past_q);
+        }
+        else
+        {
+            update_jni(java->jni_struct, java, java->nb_q, java->cur_q);
+        }
+    }
     else
     {
+        java->last_past_q_flag = 0;
+
         update_jni(java->jni_struct, java, java->nb_q, java->cur_q);
     }
 }

MBsysC/mbs_common/mbs_realtime/realtime/realtime_ext.c

@@ -116,6 +116,8 @@ Realtime_java* init_realtime_java(void *realtime_options, MbsData* mbs_data)
 
     java->flag_buffer_round = 0;
 
+    java->last_past_q_flag = 0;
+
     java->cur_q = (double*) malloc(nb_q * sizeof(double));
     for(i=0; i<nb_q; i++)
     {

MBsysC/mbs_common/mbs_realtime/realtime/realtime_ext.h

@@ -54,6 +54,7 @@ typedef struct Realtime_java
     int visu_past_flag;    ///< 1 to view what happened before, 0 otherwise
     double t_visu_past;    ///< requested time for past visualization
     int flag_buffer_round; ///< 1 if buffer already filled, 0 otherwise
+    int last_past_q_flag;  ///< 1 if last visu was with past_q, 0 otherwise
 
     char *mbs_file;    ///< path and file name fot the .mbs file used for Java visualization
     double *tsim_save; ///< vector saving the simulation time [s]