magnav: Outsource tilt compensation to library

apps/magnav/magnav_b2.js

@@ -53,24 +53,7 @@ function newHeading(m,h){
 
 var candraw = false;
 var CALIBDATA = require("Storage").readJSON("magnav.json",1)||null;
-
+const tiltfixread = require("magnav").tiltfixread;
-function tiltfixread(O,S){
-  "ram"
-  var m = Bangle.getCompass();
-  var g = Bangle.getAccel();
-  m.dx =(m.x-O.x)*S.x; m.dy=(m.y-O.y)*S.y; m.dz=(m.z-O.z)*S.z;
-  var d = Math.atan2(-m.dx,m.dy)*180/Math.PI;
-  if (d<0) d+=360;
-  var phi = Math.atan(-g.x/-g.z);
-  var cosphi = Math.cos(phi), sinphi = Math.sin(phi);
-  var theta = Math.atan(-g.y/(-g.x*sinphi-g.z*cosphi));
-  var costheta = Math.cos(theta), sintheta = Math.sin(theta);
-  var xh = m.dy*costheta + m.dx*sinphi*sintheta + m.dz*cosphi*sintheta;
-  var yh = m.dz*sinphi - m.dx*cosphi;
-  var psi = Math.atan2(yh,xh)*180/Math.PI;
-  if (psi<0) psi+=360;
-  return psi;
-}
 
 // Note actual mag is 360-m, error in firmware
 function reading() {
@@ -94,30 +77,6 @@ function reading() {
   g.flip();
 }
 
-function calibrate(){
-  var max={x:-32000, y:-32000, z:-32000},
-      min={x:32000, y:32000, z:32000};
-  var ref = setInterval(()=>{
-      var m = Bangle.getCompass();
-      max.x = m.x>max.x?m.x:max.x;
-      max.y = m.y>max.y?m.y:max.y;
-      max.z = m.z>max.z?m.z:max.z;
-      min.x = m.x<min.x?m.x:min.x;
-      min.y = m.y<min.y?m.y:min.y;
-      min.z = m.z<min.z?m.z:min.z;
-  }, 100);
-  return new Promise((resolve) => {
-     setTimeout(()=>{
-       if(ref) clearInterval(ref);
-       var offset = {x:(max.x+min.x)/2,y:(max.y+min.y)/2,z:(max.z+min.z)/2};
-       var delta  = {x:(max.x-min.x)/2,y:(max.y-min.y)/2,z:(max.z-min.z)/2};
-       var avg = (delta.x+delta.y+delta.z)/3;
-       var scale = {x:avg/delta.x, y:avg/delta.y, z:avg/delta.z};
-       resolve({offset:offset,scale:scale});
-     },20000);
-  });
-}
-
 var calibrating=false;
 function docalibrate(first){
     calibrating=true;
@@ -137,7 +96,7 @@ function docalibrate(first){
           g.drawString("Fig 8s to",88,Ypos);
           g.drawString("Calibrate",88,Ypos+18);
           g.flip();
-          calibrate().then((r)=>{
+          require("magnav").calibrate().then((r)=>{
             CALIBDATA=r;
             require("Storage").write("magnav.json",r);
             restart();