BangleApps/apps/mandel/mandel.min.js

var aux = new Float32Array(8);
var p_aux = E.getAddressOf(aux, true);
aux[0] = -2;
aux[1] = -1.5;
aux[2] = 1;
aux[3] = 1.5;

var buf_height = 40;

var frameX1=0, frameX2=239, frameY1=0, frameY2=239;
var frameCorner = 0;

var imbuf = Graphics.createArrayBuffer(240, buf_height, 16);
var imbufaddr = E.getAddressOf(imbuf.buffer, true);
var mimg = {
  width :imbuf.getWidth(),
  height:imbuf.getHeight(),
  bpp   :16,
  buffer:imbuf.buffer
};

var c = (function(){
  var bin=atob("0O0EepDtAFrQ7QFK0O0COpDtAzqf7URK/e7nei3p8EMX7pBa0O0Fev3u53rF68V8F+6QStDtBnr97ud6ACMX7pCK0O0Hev3u53q47gAqF+6QmvfuABq/7ggaTEVi2gzrAwaeRgHrRgYqRvfuCCqu6wUDQkUTRETaB+4QKnPuxXq47sd6HyNn7od6B+4QSsfuhGq47sd6c+5kenbuhWpn7od6n+0iesfuhFrw7kd6de6kWgE7E/D/AxPQ9O7CevHuEPoO3fTu4Xrx7hD6CdW07sF68e4Q+gTdtO7ievHuEPoR1NgBwPMKAEPqQzMDQ8PzByBg8wcHY/MPJyb4EnABMrXnATSp5yfuR2rw7mUKp+6nanfup3rn7icKdu4merDuYHrG573o8IMAAHBDAAAAAA==");
  return {
    mandel:E.nativeCall(1, "void(int, int)", bin),
  };
})();

function drawRectangle(x1, y1, x2, y2) {
  if (frameCorner==1) g.setColor(1, 0, 0);
  else g.setColor(1, 1, 1);
  g.drawLine(x1, y1, x2, y1).drawLine(x1, y1, x1, y2);
  if (frameCorner==2) g.setColor(1, 0, 0);
  else g.setColor(1, 1, 1);
  g.drawLine(x1, y2, x2, y2).drawLine(x2, y1, x2, y2);
}

function restoreRow(y) {
  mimg.width = 240;
  mimg.height = 1;
  aux[4] = 0;
  aux[5] = y;
  aux[6] = 240;
  aux[7] = y+1;
  c.mandel(p_aux, imbufaddr);
  g.drawImage(mimg, 0, y);
}

function restoreCol(x) {
  mimg.width = 1;
  mimg.height = 240;
  aux[4] = x;
  aux[5] = 0;
  aux[6] = x+1;
  aux[7] = 240;
  c.mandel(p_aux, imbufaddr);
  g.drawImage(mimg, x, 0);
}

function moveUp() {
  restoreCol(frameX1);
  restoreCol(frameX2);
  if (frameCorner==1 && frameY1>3) {
    restoreRow(frameY1);
    frameY1 -= 4;
  }
  if (frameCorner==2 && frameY2>3) {
    restoreRow(frameY2);
    frameY2 -= 4;
  }
  drawRectangle(frameX1, frameY1, frameX2, frameY2);
}

function moveDown() {
  restoreCol(frameX1);
  restoreCol(frameX2);
  if (frameCorner==1 && frameY1<235) {
    restoreRow(frameY1);
    frameY1 += 4;
  }
  if (frameCorner==2 && frameY2<235) {
    restoreRow(frameY2);
    frameY2 += 4;
  }
  drawRectangle(frameX1, frameY1, frameX2, frameY2);
}

function moveRight() {
  restoreRow(frameY1);
  restoreRow(frameY2);
  if (frameCorner==1 && frameX1<235) {
    restoreCol(frameX1);
    frameX1 += 4;
  }
  if (frameCorner==2 && frameX2<235) {
    restoreCol(frameX2);
    frameX2 += 4;
  }
  drawRectangle(frameX1, frameY1, frameX2, frameY2);
}

function moveLeft() {
  restoreRow(frameY1);
  restoreRow(frameY2);
  if (frameCorner==1 && frameX1>3) {
    restoreCol(frameX1);
    frameX1 -= 4;
  }
  if (frameCorner==2 && frameX2>3) {
    restoreCol(frameX2);
    frameX2 -= 4;
  }
  drawRectangle(frameX1, frameY1, frameX2, frameY2);
}


function toggleFrame() {
  if (frameCorner<2) {
    frameCorner++;
    drawRectangle(frameX1, frameY1, frameX2, frameY2);
  }
  else {
    frameCorner = 0;
    var mincx = aux[0] + (aux[2]-aux[0])*frameX1/240.0;
    var maxcx = aux[0] + (aux[2]-aux[0])*frameX2/240.0;
    var mincy = aux[1] + (aux[3]-aux[1])*frameY1/240.0;
    var maxcy = aux[1] + (aux[3]-aux[1])*frameY2/240.0;
    aux[0] = mincx;
    aux[1] = mincy;
    aux[2] = maxcx;
    aux[3] = maxcy;
    drawIt();
  }
}

setWatch(toggleFrame, BTN2, {repeat: true});
setWatch(moveUp, BTN1, {repeat: true});
setWatch(moveDown, BTN3, {repeat: true});
Bangle.on('touch', function(button) {
  switch(button) {
    case 1: moveLeft(); break;
    case 2: moveRight(); break;
  }
});


function drawIt() {
  aux[4] = 0;
  aux[5] = 0;
  aux[6] = 240;
  aux[7] = buf_height;
  mimg.width = 240;
  mimg.height = buf_height;
  for (var y=0; y<240/buf_height; ++y) {
    c.mandel(p_aux, imbufaddr);
    aux[5] += buf_height;
    aux[7] += buf_height;
    g.drawImage(mimg, 0, y*buf_height);
  }
}

setTimeout(drawIt, 50);