Update app.js

apps/speedalt2/app.js

@@ -2,8 +2,9 @@
 Speed and Altitude [speedalt2]
 Mike Bennett mike[at]kereru.com
 1.10 : add inverted colours
+1.11 : Add VMG screen
 */
-var v = '1.10';
+var v = '1.11';
 
 /*kalmanjs, Wouter Bulten, MIT, https://github.com/wouterbulten/kalmanjs */
 var KalmanFilter = (function () {
@@ -194,6 +195,10 @@ var maxSpd = 0;
 var maxAlt = 0;
 var maxN = 0;    // counter. Only start comparing for max after a certain number of fixes to allow kalman filter to have smoohed the data.
 
+// Previous values for calculating VMG.
+var lastDist = -1;
+var lastTime = -1;
+
 var emulator = (process.env.BOARD=="EMSCRIPTEN")?1:0;  // 1 = running in emulator. Supplies test values;
 
 var wp = {};        // Waypoint to use for distance from cur position.
@@ -201,6 +206,8 @@ var wp = {};        // Waypoint to use for distance from cur position.
 function nxtWp(){
   cfg.wp++;
   loadWp();
+  lastDist = -1;  // Reset VMG calcs
+  lastTime = -1;
 }
 
 function loadWp() {
@@ -219,11 +226,11 @@ function distance(a,b){
   var x = radians(a.lon-b.lon) * Math.cos(radians((a.lat+b.lat)/2));
   var y = radians(b.lat-a.lat);
   
-  // Distance in selected units
+  // Distance in metres
   var d = Math.sqrt(x*x + y*y) * 6371000;
-  d = (d/parseFloat(cfg.dist)).toFixed(2);
+//  d = (d/parseFloat(cfg.dist)).toFixed(2);
-  if ( d >= 100 ) d = parseFloat(d).toFixed(1);
+//  if ( d >= 100 ) d = parseFloat(d).toFixed(1);
-  if ( d >= 1000 ) d = parseFloat(d).toFixed(0);
+//  if ( d >= 1000 ) d = parseFloat(d).toFixed(0);
 
   return d;
 }
@@ -328,8 +335,8 @@ function drawClock() {
 function drawWP(wp) {
   buf.setColor(3);  
   buf.setFontAlign(0,1); //left, bottom
-  buf.setFontVector(48);
+  buf.setFontVector(40);
-  buf.drawString(wp,120,140);  
+  buf.drawString(wp,120,132);  
 }
 
 function drawSats(sats) {
@@ -370,6 +377,7 @@ if ( emulator ) {
   var ew = '';
   var lon = '---.--';
   var sats = '---';
+  var vmg = '---';
   
   // Waypoint name
   var wpName = wp.name;
@@ -389,17 +397,10 @@ if ( emulator ) {
     }
 
     // Speed
-    if ( cfg.spd == 0 ) {
+    sp = parseFloat(lf.speed)/parseFloat(cfg.spd); // Calculate for selected units
-      m = require("locale").speed(lf.speed).match(/([0-9,\.]+)(.*)/); // regex splits numbers from units
-      sp = parseFloat(m[1]);
-      cfg.spd_unit = m[2];
-    }
-    else sp = parseFloat(lf.speed)/parseFloat(cfg.spd); // Calculate for selected units
-
     if ( sp < 10 ) sp = sp.toFixed(1);
     else sp = Math.round(sp);
     if (isNaN(sp)) sp = '---';
-    
     if (parseFloat(sp) > parseFloat(maxSpd) && maxN > 15 ) maxSpd = sp;
 
     // Altitude
@@ -408,9 +409,34 @@ if ( emulator ) {
     if (parseFloat(al) > parseFloat(maxAlt) && maxN > 15 ) maxAlt = al;
     if (isNaN(al)) al = '---';
 
-    // Distance to waypoint
+    // Distance to waypoint and vmg
     di = distance(lf,wp);
-    if (isNaN(di)) di = '--------';
+ 
+//lastDist = 13640;
+//lastTime = (getTime()/1000) - 10;
+    
+    if ( lastDist != -1 && ! isNaN(lastDist)) {
+//console.log('     Distance : '+di);    
+//console.log('last.Distance : '+lastDist);    
+//console.log('last.Time : '+lastTime);    
+
+      // Have two WP distances and a time. Calc speed
+      vmg = ((lastDist-di)/1000)/((getTime()/1000-lastTime)/3600);   // k/h
+      vmg = vmg/parseFloat(cfg.spd); // Calculate for selected units
+//console.log('VMG : '+vmg);    
+    }
+    lastDist = di;
+    lastTime = getTime()/1000;  // secs
+
+    di = (di/parseFloat(cfg.dist)).toFixed(2);
+    if ( di >= 100 ) di = parseFloat(di).toFixed(1);
+    if ( di >= 1000 ) di = parseFloat(di).toFixed(0);
+
+    if ( Math.abs(vmg) < 10 ) vmg = vmg.toFixed(1);
+    else vmg = Math.round(vmg);
+    
+    if (isNaN(vmg)) vmg = '---';
+    if (isNaN(di)) di = '------';
 
     // Age of last fix (secs)
     age = Math.max(0,Math.round(getTime())-(lf.time.getTime()/1000));
@@ -490,6 +516,18 @@ if ( emulator ) {
   }
 
   if ( cfg.modeA == 3 ) {
+    // VMG
+      drawScrn({
+        val:vmg,
+        unit:cfg.spd_unit,
+        sats:sats,
+        age:age,
+        max:'VMG',
+        wp:wpName
+      });
+  }
+
+  if ( cfg.modeA == 4 ) {
     // Position
     drawPosn({
         sats:sats,
@@ -501,7 +539,7 @@ if ( emulator ) {
       });
   }
   
-  if ( cfg.modeA == 4 )  {
+  if ( cfg.modeA == 5 )  {
     // Large clock
     drawClock();
   }
@@ -510,14 +548,14 @@ if ( emulator ) {
 
 function prevScrn() {
     cfg.modeA = cfg.modeA-1;
-    if ( cfg.modeA < 0 ) cfg.modeA = 4;
+    if ( cfg.modeA < 0 ) cfg.modeA = 5;
     savSettings();
     onGPS(lf); 
 }
 
 function nextScrn() {
     cfg.modeA = cfg.modeA+1;
-    if ( cfg.modeA > 4 ) cfg.modeA = 0;
+    if ( cfg.modeA > 5 ) cfg.modeA = 0;
     savSettings();
     onGPS(lf); 
 }
@@ -529,14 +567,14 @@ function nextFunc(dur) {
       if ( dur < 2 ) showMax = !showMax;   // Short press toggle fix/max display
       else { maxSpd = 0; maxAlt = 0; }  // Long press resets max values.
     }
-    else  if ( cfg.modeA == 2) nxtWp();  // Dist mode - Select next waypoint
+    else  if ( cfg.modeA == 2 || cfg.modeA == 3) nxtWp();  // Dist or VMG mode - Select next waypoint
     onGPS(lf);
 }
 
 
 function updateClock() {
   if (!canDraw) return;
-  if ( cfg.modeA != 4 )  return;
+  if ( cfg.modeA != 5 )  return;
   drawClock(); 
   if ( emulator ) {maxSpd++;maxAlt++;}
 }
@@ -646,15 +684,15 @@ console.log('MDL');
 // Read settings. 
 let cfg = require('Storage').readJSON('speedalt2.json',1)||{};
 
-cfg.spd = cfg.spd||0;  // Multiplier for speed unit conversions. 0 = use the locale values for speed
+cfg.spd = cfg.spd||1;  // Multiplier for speed unit conversions. 0 = use the locale values for speed
-cfg.spd_unit = cfg.spd_unit||'';  // Displayed speed unit
+cfg.spd_unit = cfg.spd_unit||'kph';  // Displayed speed unit
 cfg.alt = cfg.alt||0.3048;// Multiplier for altitude unit conversions.
 cfg.alt_unit = cfg.alt_unit||'feet';  // Displayed altitude units
 cfg.dist = cfg.dist||1000;// Multiplier for distnce unit conversions.
 cfg.dist_unit = cfg.dist_unit||'km';  // Displayed altitude units
 cfg.colour = cfg.colour||0;          // Colour scheme.
 cfg.wp = cfg.wp||0;        // Last selected waypoint for dist
-cfg.modeA = cfg.modeA||0;    // 0=Speed 1=Alt 2=Dist 3=Position 4=Clock 
+cfg.modeA = cfg.modeA||0;    // 0=Speed 1=Alt 2=Dist 3 = vmg 4=Position 5=Clock 
 cfg.primSpd = cfg.primSpd||0;    // 1 = Spd in primary, 0 = Spd in secondary
 
 cfg.spdFilt = cfg.spdFilt==undefined?true:cfg.spdFilt;