BangleApps/apps/speedalt/app.js

/*
Speed and Altitude [speedalt]
Ver : 1.03
Mike Bennett mike[at]kereru.com
*/

const dbg = 0;

var buf = Graphics.createArrayBuffer(240,160,4,{msb:true});

// Load fonts
require("Font7x11Numeric7Seg").add(Graphics);

var lastFix = {fix:0,satellites:0};
var primaryDisp = 1;      // 1 = Speed in primary display. 0 = alt/dist in primary
var altDisp = 1;            // 1 = alt, 0 = dist to wp
var showMax = 0;        // 1 = display the max values. 0 = display the cur fix
var maxPress = 0;      // Time max button pressed. Used to calculate short or long press.
var canDraw = 1;
var time = '';    // Last time string displayed. Re displayed in background colour to remove before drawing new time.
var ledID = 0;      // ID of interval doing the LED flasher
var ledOn = 0;      // LED state flag for flasher

var max = {};
max.spd = 0;
max.alt = 0;

var emulator = 0;
if (process.env.BOARD=="EMSCRIPTEN") emulator = 1;  // 1 = running in emulator. Supplies test values;

var waypoints = require("Storage").readJSON("waypoints.json")||[{name:"NONE"}];
var wpindex=0;
var wp = {};        // Waypoint to use for distance from cur position.

function nextwp(inc){
  if (altDisp) return;
  wpindex+=inc;
  if (wpindex>=waypoints.length) wpindex=0;
  if (wpindex<0) wpindex = waypoints.length-1;
  wp = waypoints[wpindex];
}

function radians(a) {
  return a*Math.PI/180;
}

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
  var d = Math.sqrt(x*x + y*y) * 6371000;
  d = (d/parseFloat(settings.dist)).toFixed(2);
  if ( d >= 100 ) d = parseFloat(d).toFixed(1);
  if ( d >= 1000 ) d = parseFloat(d).toFixed(0);

  return d;
}

function drawFix(speed,units,sats,alt,alt_units,age,fix) {
  if (!canDraw) return;

  buf.clear();

  if ( fix ) drawLED();  // Use LED to indicate current mode
  else drawLEDFlash(); // Flashing indicate no fix so displaying last known
  
  var val = '';  
  var u='';
  
  // Primary Display
  val = speed.toString();
  if ( !primaryDisp ) val = alt.toString();
  
  // Primary Units
  u = settings.spd_unit;
  if ( !primaryDisp ) u = alt_units;

  drawPrimary(val,u);
  
  // Secondary Display
  val = alt.toString();
  if ( !primaryDisp ) val = speed.toString();

  // Secondary Units
  u = alt_units;
  if ( !primaryDisp ) u = settings.spd_unit;
  
  drawSecondary(val,u);
  
  // Time
  drawTime();

  // Waypoint name
  drawWP();
  
  //Sats
  if ( fix ) drawSats('Sats:'+sats);
  else drawSats('Age:'+age);

  g.reset();
  g.drawImage(img,0,40);
  
}

function drawPrimary(n,u) {
 
  // Primary Display
  
  var s=40;    // Font size
  if ( n.length <= 7 ) s=48;
  if ( n.length <= 6 ) s=55;
  if ( n.length <= 5 ) s=68;
  if ( n.length <= 4 ) s=85;
  if ( n.length <= 3 ) s=110;
        
  buf.setFontAlign(0,-1); //Centre 
  buf.setColor(1);  

  buf.setFontVector(s);
  buf.drawString(n,110,0);
    
    // Primary Units
  buf.setFontAlign(1,-1,3); //right
  buf.setColor(2);  
  buf.setFontVector(25);
  buf.drawString(u,210,0);  
}

function drawSecondary(n,u) {

  var s=180;    // units X position
  if ( n.length <= 5 ) s=155;
  if ( n.length <= 4 ) s=125;
  if ( n.length <= 3 ) s=100;
  if ( n.length <= 2 ) s=65;
  if ( n.length <= 1 ) s=35;
  
  buf.setFontAlign(-1,1); //left, bottom 
  buf.setColor(1);  
  buf.setFontVector(45);
  buf.drawString(n,5,140);
    
  // Secondary Units
  buf.setFontAlign(-1,1); //left, bottom
  buf.setColor(2);  
  buf.setFontVector(25);
  buf.drawString(u,s,135);
}

function drawLED() {
  if ( ledID > 0 ) clearInterval(ledID);  // Stop the flasher
  drawLEDCircle(0);
}

function drawLEDFlash() {
  if ( ledID > 0 ) clearInterval(ledID);  // Stop the flasher
  ledOn = 0;
  ledID = setInterval(function() {ledOn=!ledOn;drawLEDCircle(ledOn);},500); // Toggle the LED

}

function drawLEDCircle(rst) {
  var x=225;
  var y=120;
  var r=10;
  if ( rst ) buf.setColor(0);  // background = off
  else if ( altDisp ) buf.setColor(5);    // blue = Speed/Alt mode
  else buf.setColor(4); // red = Speed/Dist mode
  buf.fillCircle(x,y,r);
  g.reset();
  g.drawImage(img,0,40);
}

function drawTime() {
  var x = 0;
  var y = 160;

  buf.setFont("7x11Numeric7Seg", 2);
  buf.setFontAlign(-1,1); //left, bottom

  buf.setColor(0);
  buf.drawString(time,x,y);
  time = require("locale").time(new Date(),1);
  buf.setColor(3);  
  buf.drawString(time,x,y);
}

function drawWP() {
  var nm = wp.name;
  if ( nm == undefined ) nm = '';
  if ( nm == 'NONE' ) nm = '';
  if ( altDisp ) nm='';
  
  buf.setFontAlign(-12,1); //left, bottom
  buf.setColor(2);  
//  buf.setFont("6x8", 1);
  buf.setFontVector(20);
  buf.drawString(nm.substring(0,6),77,160);  
 
}

function drawSats(sats) {

  if ( showMax && altDisp ) {
    buf.setFontVector(20);
    buf.setFontAlign(0,1); //centre, bottom
    buf.setColor(2); 
    buf.drawString("MAX",120,160);
  }
  
  buf.setColor(3);  
  buf.setFont("6x8", 2);
  buf.setFontAlign(1,1); //right, bottom
  buf.drawString(sats,240,160);  
}

function onGPS(fix) {
  
 if ( emulator ) {
    fix.fix = 1;
    fix.speed = 125;
    fix.alt = 390;
    fix.lat = -38.92;
    fix.lon = 175.7613350;   
    fix.course = 245;
    fix.satellites = 12;
    fix.time = new Date();
  }
  
  if (fix.fix) lastFix = fix;

  var m;

  speed = '---';        
    alt = '---';
    dist = '---';
    age = '---';
  
    if (lastFix.fix == 1 ) {  
      // Speed
      if ( settings.spd == 0 ) {
        m = require("locale").speed(lastFix.speed).match(/([0-9,\.]+)(.*)/); // regex splits numbers from units
        speed = m[1];
        settings.spd_unit = m[2];
      }
      else {
        // Calculate for selected units
        speed = lastFix.speed;
        if ( emulator ) speed = '100';
        speed = Math.round(parseFloat(speed)/parseFloat(settings.spd));
      }
      if (parseFloat(speed) > parseFloat(max.spd) ) max.spd = parseFloat(speed);

      // Altitude
      alt = lastFix.alt;
      alt = Math.round(parseFloat(alt)/parseFloat(settings.alt));
      if (parseFloat(alt) > parseFloat(max.alt) ) max.alt = parseFloat(alt);

      // Distance to waypoint
      dist = distance(lastFix,wp);
      if (isNaN(dist)) dist = 0;

      // Age of last fix (secs)
      age = Math.max(0,Math.round(getTime())-(lastFix.time.getTime()/1000));
      if ( age > 90 ) age = '>90';
    }
      
    if ( altDisp ) {
      if ( showMax ) {
        // Speed and alt maximums
        drawFix(max.spd,settings.spd_unit,fix.satellites,max.alt,settings.alt_unit,age,fix.fix);
      }
      else {
        // Show speed/altitude
        drawFix(speed,settings.spd_unit,fix.satellites,alt,settings.alt_unit,age,fix.fix);
      }
    }
    else {
      // Show speed/distance
      if ( dist <= 0 ) {
        // No WP selected
        drawFix(speed,settings.spd_unit,fix.satellites,'','',age,fix.fix);
      }
      else {
        drawFix(speed,settings.spd_unit,fix.satellites,dist,settings.dist_unit,age,fix.fix);
      }
    }

}


function toggleDisplay() {
  primaryDisp = !primaryDisp;
  onGPS(lastFix);  // Update display
}

function toggleAltDist() {
  altDisp = !altDisp;
  onGPS(lastFix); 
}

function setButtons(){

  // Spd+Dist : Select next waypoint
  setWatch(btnPressed, BTN1,{repeat:true,edge:"rising"});
  setWatch(btnReleased, BTN1,{repeat:true,edge:"falling"});

  // Show launcher when middle button pressed
  setWatch(Bangle.showLauncher, BTN2, {repeat:false,edge:"falling"});

  // Touch left screen to toggle display
  setWatch(toggleDisplay, BTN4, {repeat:true,edge:"rising"});

  // Touch left screen to toggle between alt or dist
  setWatch(toggleAltDist, BTN5, {repeat:true,edge:"rising"});
  
}

function btnPressed() {
  maxPress = getTime();
}

function btnReleased() {
  var dur = getTime()-maxPress;
  if ( altDisp ) {
    // Spd+Alt mode - Switch between fix and MAX
    if ( dur < 2 ) {
      showMax = !showMax;   // Short press toggle fix/max display
    }
    else {
      max.spd = 0;  // Long press resets max values.
      max.alt = 0;
    }
  }
  else {
    // Spd+Dist mode - Select next waypoint
    nextwp(1);
  }
  onGPS(lastFix);
}

function updateClock() {
  if ( dbg ) print('Updating clock');
  if (!canDraw) return;

  drawTime(); 
  g.reset();
  g.drawImage(img,0,40);
//  g.flip();
  
  if ( emulator ) {
    max.spd++;
    max.alt++;
  }
  
}

function startDraw(){
  canDraw=true;
  g.clear();
  Bangle.drawWidgets();
  onGPS(lastFix);  // draw app screen
}

function stopDraw() {
  canDraw=false;
}

// =Main Prog

// Read settings. 
let settings = require('Storage').readJSON('speedalt.json',1)||{};

settings.spd = settings.spd||0;  // Multiplier for speed unit conversions. 0 = use the locale values for speed
settings.spd_unit = settings.spd_unit||'';  // Displayed speed unit
settings.alt = settings.alt||0.3048;// Multiplier for altitude unit conversions.
settings.alt_unit = settings.alt_unit||'feet';  // Displayed altitude units
settings.dist = settings.dist||1000;// Multiplier for distnce unit conversions.
settings.dist_unit = settings.dist_unit||'km';  // Displayed altitude units
settings.colour = settings.colour||0;          // Colour scheme. 

/*
Colour Pallet Idx
0 : Background (black)
1 : Speed/Alt
2 : Units
3 : Sats
4 : led1 (red)
5 : led2 (blue)
*/
var img = {
  width:buf.getWidth(),
  height:buf.getHeight(),
  bpp:4,
  buffer:buf.buffer,
  palette:new Uint16Array([0,0x4FE0,0xEFE0,0x07DB,0xF800,0x051F,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF])
};

/*
if ( settings.colour == 1 ) img.palette = new Uint16Array([0,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF]);
if ( settings.colour == 2 ) img.palette = new Uint16Array([0,0xFF800,0xF800,0xF800,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF]);
*/

// Find speed unit if using locale speed
if ( settings.spd == 0 ) {
  var strSpeed = require("locale").speed(1);
  m = strSpeed.match(/([0-9,\.]+)(.*)/); // regex splits numbers from units
  settings.spd_unit = m[2];
}

var SCREENACCESS = {
      withApp:true,
      request:function(){
        this.withApp=false;
        stopDraw();
        clearWatch();
      },
      release:function(){
        this.withApp=true;
        startDraw(); 
        setButtons();
      }
}; 

Bangle.on('lcdPower',function(on) {
  if (!SCREENACCESS.withApp) return;
  if (on) {
    startDraw();
  } else {
    stopDraw();
  }
});

// All set up. Lets go.
g.clear();
Bangle.setLCDBrightness(1);
Bangle.loadWidgets();
Bangle.drawWidgets();
Bangle.setGPSPower(1);

onGPS(lastFix);
Bangle.on('GPS', onGPS);

setButtons();
setInterval(updateClock, 30000);