Etienne improves NMEA handling of GPGSA and DOPs.

diff --git a/gpsbabel/nmea.c b/gpsbabel/nmea.c
index 5801029dff3cdf1a3fa2fb96ace836708b5455ff..27b48bd037cd3953bd0dc31218b26e8154321372 100644 (file)
--- a/gpsbabel/nmea.c
+++ b/gpsbabel/nmea.c
@@ -268,7 +268,7 @@ gpgga_parse(char *ibuf)
        waypt->hdop     = hdop;
 
        if (fix==1) {
-               waypt->fix  = (nsats>4)?(fix_3d):(fix_2d);
+               waypt->fix  = (nsats>3)?(fix_3d):(fix_2d);
        }
        else if (fix==2)
        {
@@ -318,9 +318,17 @@ gprmc_parse(char *ibuf)
        tm.tm_mday = dmy;
        creation_time = mkgmtime(&tm);
 
-       if (posn_type == gpgga)
+       if (posn_type == gpgga) {
+               /* capture useful data update and exit */
+               if (curr_waypt) {
+                       if (curr_waypt->speed<=0) 
+                               curr_waypt->speed       = speed*kts2mps;
+                       if (curr_waypt->course<=0)
+                               curr_waypt->course      = course;
+               }
                return;
-
+       }
+               
        waypt  = waypt_new();
 
        waypt->speed    = speed*kts2mps;
@@ -391,16 +399,30 @@ gpgsa_parse(char *ibuf)
        char fixauto;
        char fix;
        int  prn[12];
-       int  cnt;
-       float pdop = 0;
-       float hdop = 0;
-       float vdop = 0;
+       int  scn,cnt;
+       float pdop=0,hdop=0,vdop=0;
+       char*   tok=0;
+
+       memset(prn,0xff,sizeof(prn));
 
-       sscanf(ibuf,"$GPGSA,%c,%c,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%f,%f,%f",
+       scn = sscanf(ibuf,"$GPGSA,%c,%c,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d",
                &fixauto, &fix,
                &prn[0],&prn[1],&prn[2],&prn[3],&prn[4],&prn[5],
-               &prn[6],&prn[7],&prn[8],&prn[9],&prn[10],&prn[11],
-               &pdop,&hdop,&vdop);
+               &prn[6],&prn[7],&prn[8],&prn[9],&prn[10],&prn[11]);
+
+       /* 
+               sscanf has scanned all the leftmost elements
+               we'll rescan by skipping 15 commas to the dops
+       */
+       tok = ibuf;
+       for (cnt=0;(tok)&&(cnt<15);cnt++)
+       {
+               tok = strchr(tok,',');
+               if (!tok) break;
+               tok++;
+       }
+       if (tok) sscanf(tok,"%f,%f,%f",&pdop,&hdop,&vdop);
+       
 
        if (curr_waypt) {
 
@@ -408,9 +430,10 @@ gpgsa_parse(char *ibuf)
                        if      (fix=='3')      curr_waypt->fix=fix_3d;
                        else if (fix=='2')      curr_waypt->fix=fix_2d;
                }
-               if (pdop > 0) curr_waypt->pdop = pdop;
-               if (hdop > 0) curr_waypt->hdop = hdop;
-               if (vdop > 0) curr_waypt->vdop = vdop;
+       
+               curr_waypt->pdop = pdop;
+               curr_waypt->hdop = hdop;
+               curr_waypt->vdop = vdop;
                
                if (curr_waypt->sat  <= 0)      {
                        for (cnt=0;cnt<12;cnt++)
@@ -427,12 +450,12 @@ gpvtg_parse(char *ibuf)
        char    ct;
        float   magcourse;
        char    cm;
-       float   speed_n;
+       double  speed_n;
        char    cn;
-       float   speed_k;
+       double  speed_k;
        char    ck;     
       
-       sscanf(ibuf,"$GPVTG,%f,%c,%f,%c,%f,%c,%f,%c",
+       sscanf(ibuf,"$GPVTG,%f,%c,%f,%c,%lf,%c,%lf,%c",
                &course,&ct,&magcourse,&cm,&speed_n,&cn,&speed_k,&ck);
                
        if (curr_waypt) {
@@ -539,6 +562,7 @@ void
 nmea_trackpt_pr(const waypoint *wpt)
 {
        char obuf[200];
+       char fix='0';
        double lat,lon;
        int cksum;
        struct tm *tm;
@@ -555,13 +579,26 @@ nmea_trackpt_pr(const waypoint *wpt)
                hms = 0;
        }
 
+       switch (wpt->fix) 
+       {
+       case fix_dgps: 
+               fix='2';
+               /* or */
+       case fix_3d:
+       case fix_2d:
+               fix='1';
+               break;
+       default:
+               fix='0';
+       }
+
        snprintf(obuf, sizeof(obuf), "GPGGA,%06d,%08.3f,%c,%09.3f,%c,%c,%02d,%.1f,%.3f,M,0.0,M,,",
                        hms,
                        fabs(lat), lat < 0 ? 'S' : 'N',
                        fabs(lon), lon < 0 ? 'W' : 'E',
-                       (wpt->fix==fix_dgps)?('2'):('1'),
-                       wpt->sat,
-                       wpt->hdop,
+                       fix,
+                       (wpt->sat>0)?(wpt->sat):(0),
+                       (wpt->hdop>0)?(wpt->hdop):(0.0),
                        wpt->altitude == unknown_alt ? 0 : wpt->altitude);
        cksum = nmea_cksum(obuf);
        fprintf(file_out, "$%s*%02X\n", obuf, cksum);
@@ -569,18 +606,36 @@ nmea_trackpt_pr(const waypoint *wpt)
        if (    (wpt->course>=0) ||
                (wpt->speed>0)     )
        {
-               snprintf(obuf,sizeof(obuf),"$GPVTG,%f,T,0,M,%f,N,%f,K",
-               wpt->course,
-               wpt->speed / kts2mps,
-               wpt->speed / kmh2mps);
+
+               snprintf(obuf,sizeof(obuf),"GPVTG,%.3f,T,0,M,%.3f,N,%.3f,K",
+                       (wpt->course>=0)?(wpt->course):(0),     
+                       (wpt->speed>0)?(wpt->speed / kts2mps):(0),
+                       (wpt->speed>0)?(wpt->speed / kmh2mps):(0) );
+
+               cksum = nmea_cksum(obuf);
+               fprintf(file_out, "$%s*%02X\n", obuf, cksum);
        }
                
        if (wpt->fix!=fix_unknown) {
-               snprintf(obuf,sizeof(obuf),"$GPGSA,A,%c,,,,,,,,,,,,,%f,%f,%f",
-                       ((wpt->fix==fix_dgps)||(wpt->fix==fix_3d))?'3':'2',
-                       wpt->pdop,
-                       wpt->hdop,
-                       wpt->vdop);
+
+               switch (wpt->fix) 
+               {
+               case fix_dgps: 
+                       /* or */
+               case fix_3d:
+                       fix='3';
+                       break;
+               case fix_2d:
+                       fix='2';
+                       break;
+               default:
+                       fix=0;
+               }
+               snprintf(obuf,sizeof(obuf),"GPGSA,A,%s,,,,,,,,,,,,,%.1f,%.1f,%.1f",
+                       fix,
+                       (wpt->pdop>0)?(wpt->pdop):(0),
+                       (wpt->hdop>0)?(wpt->hdop):(0),
+                       (wpt->vdop>0)?(wpt->vdop):(0) );
                cksum = nmea_cksum(obuf);
                fprintf(file_out, "$%s*%02X\n", obuf, cksum);
        }