BangleApps/apps/gipy/app.js

467 lines
17 KiB
JavaScript

let simulated = true;
let file_version = 2;
let code_key = 47490;
let interests_colors = [
0x780F, // Bakery, purple
0x001F, // DrinkingWater, blue
0x07FF, // Toilets, cyan
0x7BEF, // BikeShop, dark grey
0xAFE5, // ChargingStation, green yellow
0x7800, // Bank, maroon
0xF800, // Supermarket, red
0xF81F, // Table, pink
0xFD20, // Artwork, orange
0x07E0, // Pharmacy, green
];
function binary_search(array, x) {
let start = 0, end = array.length - 1;
while (start <= end){
let mid = Math.floor((start + end) / 2);
if (array[mid] < x)
start = mid + 1;
else
end = mid - 1;
}
return start;
}
class Status {
constructor(path) {
this.path = path;
this.on_path = false; // are we on the path or lost ?
this.position = null; // where we are
this.cos_direction = null; // cos of where we look at
this.sin_direction = null; // sin of where we look at
this.current_segment = null; // which segment is closest
this.reaching = null; // which waypoint are we reaching ?
this.distance_to_next_point = null; // how far are we from next point ?
let r = [0];
// let's do a reversed prefix computations on all distances:
// loop on all segments in reversed order
let previous_point = null;
for (let i = this.path.len - 1; i >= 0; i--) {
let point = this.path.point(i);
if (previous_point !== null) {
r.unshift(r[0] + point.distance(previous_point));
}
previous_point = point;
}
this.remaining_distances = r; // how much distance remains at start of each segment
}
update_position(new_position, direction) {
if (Bangle.isLocked() && this.position !== null && new_position.lon == this.position.lon && new_position.lat == this.position.lat) {
return;
}
this.cos_direction = Math.cos(-direction - Math.PI / 2.0);
this.sin_direction = Math.sin(-direction - Math.PI / 2.0);
this.position = new_position;
// detect segment we are on now
let next_segment = this.path.nearest_segment(this.position, Math.max(0, this.current_segment-1), Math.min(this.current_segment+2, path.len - 1), this.cos_direction, this.sin_direction);
if (this.is_lost(next_segment)) {
// it did not work, try anywhere
next_segment = this.path.nearest_segment(this.position, 0, path.len - 1, this.cos_direction, this.sin_direction);
}
// now check if we strayed away from path or back to it
let lost = this.is_lost(next_segment);
if (this.on_path == lost) { // if status changes
if (lost) {
Bangle.buzz(); // we lost path
setTimeout(()=>Bangle.buzz(), 500);
}
this.on_path = !lost;
}
this.current_segment = next_segment;
// check if we are nearing the next point on our path and alert the user
let next_point = this.current_segment + 1;
this.distance_to_next_point = Math.ceil(this.position.distance(this.path.point(next_point)));
if (this.reaching != next_point && this.distance_to_next_point <= 20) {
this.reaching = next_point;
let reaching_waypoint = this.path.is_waypoint(next_point);
if (reaching_waypoint) {
Bangle.buzz();
if (Bangle.isLocked()) {
Bangle.setLocked(false);
}
}
}
// re-display unless locked
if (!Bangle.isLocked() || simulated) {
this.display();
}
}
remaining_distance() {
return this.remaining_distances[this.current_segment+1] + this.position.distance(this.path.point(this.current_segment+1));
}
is_lost(segment) {
let distance_to_nearest = this.position.fake_distance_to_segment(this.path.point(segment), this.path.point(segment+1));
let meters = 6371e3 * distance_to_nearest;
return (meters > 20);
}
display() {
g.clear();
this.display_map();
this.display_interest_points();
this.display_stats();
Bangle.drawWidgets();
}
display_interest_points() {
// this is the algorithm in case we have a lot of interest points
// let's draw all points for 5 segments centered on current one
let starting_group = Math.floor(Math.max(this.current_segment-2, 0) / 3);
let ending_group = Math.floor(Math.min(this.current_segment+2, this.path.len-2) / 3);
let starting_bucket = binary_search(this.path.interests_starts, starting_group);
let ending_bucket = binary_search(this.path.interests_starts, ending_group+0.5);
// we have 5 points per bucket
for (let i = starting_bucket*5 ; i <= ending_bucket*5 ; i++) {
let index = this.path.interests_on_path[i];
let interest_point = this.path.interest_point(index);
let color = this.path.interest_color(i);
let c = interest_point.coordinates(this.position, this.cos_direction, this.sin_direction);
g.setColor(color).fillCircle(c[0], c[1], 5);
}
}
display_stats() {
let rounded_distance = Math.round(this.remaining_distance() / 100) / 10;
let total = Math.round(this.remaining_distances[0] / 100) / 10;
let now = new Date();
let minutes = now.getMinutes().toString();
if (minutes.length < 2) {
minutes = '0' + minutes;
}
let hours = now.getHours().toString();
g.setFont("6x8:2").setColor(g.theme.fg).drawString(hours + ":" + minutes, 0, g.getHeight() - 49);
g.drawString("d. " + rounded_distance + "/" + total, 0, g.getHeight() - 32);
g.drawString("seg." + (this.current_segment + 1) + "/" + path.len + " " + this.distance_to_next_point + "m", 0, g.getHeight() - 15);
}
display_map() {
// don't display all segments, only those neighbouring current segment
// this is most likely to be the correct display
// while lowering the cost a lot
let start = Math.max(this.current_segment - 5, 0);
let end = Math.min(this.current_segment + 6, this.path.len - 1);
let pos = this.position;
let cos = this.cos_direction;
let sin = this.sin_direction;
// segments
let current_segment = this.current_segment;
this.path.on_segments(function(p1, p2, i) {
if (i == current_segment + 1) {
g.setColor(0.0, 1.0, 0.0);
} else {
g.setColor(1.0, 0.0, 0.0);
}
let c1 = p1.coordinates(pos, cos, sin);
let c2 = p2.coordinates(pos, cos, sin);
g.drawLine(c1[0], c1[1], c2[0], c2[1]);
}, start, end);
// waypoints
for (let i = start ; i < end + 1 ; i++) {
let p = this.path.point(i);
let c = p.coordinates(pos, cos, sin);
if (this.path.is_waypoint(i)) {
g.setColor(g.theme.fg);
g.fillCircle(c[0], c[1], 6);
g.setColor(g.theme.bg);
g.fillCircle(c[0], c[1], 5);
}
g.setColor(g.theme.fg);
g.fillCircle(c[0], c[1], 4);
g.setColor(g.theme.bg);
g.fillCircle(c[0], c[1], 3);
}
// now display ourselves
g.setColor(g.theme.fgH);
g.fillCircle(g.getWidth() / 2, g.getHeight() / 2, 5);
}
}
class Path {
constructor(filename) {
let buffer = require("Storage").readArrayBuffer(filename);
let offset = 0;
// header
let header = Uint16Array(buffer, offset, 5);
offset += 5 * 2;
let key = header[0];
let version = header[1];
let points_number = header[2];
if ((key != code_key)||(version>file_version)) {
E.showMessage("Invalid gpc file");
return;
}
// path points
this.points = Float64Array(buffer, offset, points_number*2);
// interest points
offset += 8 * points_number * 2;
let interests_number = header[3];
this.interests_coordinates = Float64Array(buffer, offset, interests_number * 2);
offset += 8 * interests_number * 2;
this.interests_types = Uint8Array(buffer, offset, interests_number);
offset += interests_number;
// interests on path
let interests_on_path_number = header[4];
this.interests_on_path = Uint16Array(buffer, offset, interests_on_path_number);
offset += 2 * interests_on_path_number;
let starts_length = Math.ceil(interests_on_path_number / 5.0);
this.interests_starts = Uint16Array(buffer, offset, starts_length);
offset += 2 * starts_length;
}
// if start, end or steep direction change
// we are buzzing and displayed specially
is_waypoint(point_index) {
if ((point_index == 0)||(point_index == this.len -1)) {
return true;
} else {
let p1 = this.point(point_index-1);
let p2 = this.point(point_index);
let p3 = this.point(point_index+1);
let d1 = p2.minus(p1);
let d2 = p3.minus(p2);
let a1 = Math.atan2(d1.lat, d1.lon);
let a2 = Math.atan2(d2.lat, d2.lon);
let direction_change = Math.abs(a2-a1);
return ((direction_change > Math.PI / 3.0)&&(direction_change < Math.PI * 5.0/3.0));
}
}
// execute op on all segments.
// start is index of first wanted segment
// end is 1 after index of last wanted segment
on_segments(op, start, end) {
let previous_point = null;
for (let i = start; i < end + 1; i++) {
let point = new Point(this.points[2 * i], this.points[2 * i + 1]);
if (previous_point !== null) {
op(previous_point, point, i);
}
previous_point = point;
}
}
// return point at given index
point(index) {
let lon = this.points[2 * index];
let lat = this.points[2 * index + 1];
return new Point(lon, lat);
}
interest_point(index) {
let lon = this.interests_coordinates[2 * index];
let lat = this.interests_coordinates[2 * index + 1];
return new Point(lon, lat);
}
interest_color(index) {
return interests_colors[this.interests_types[index]];
}
// return index of segment which is nearest from point.
// we need a direction because we need there is an ambiguity
// for overlapping segments which are taken once to go and once to come back.
// (in the other direction).
nearest_segment(point, start, end, cos_direction, sin_direction) {
// we are going to compute two min distances, one for each direction.
let indices = [0, 0];
let mins = [Number.MAX_VALUE, Number.MAX_VALUE];
this.on_segments(function(p1, p2, i) {
// we use the dot product to figure out if oriented correctly
let distance = point.fake_distance_to_segment(p1, p2);
let diff = p2.minus(p1);
let dot = cos_direction * diff.lon + sin_direction * diff.lat;
let orientation = + (dot < 0); // index 0 is good orientation
if (distance <= mins[orientation]) {
mins[orientation] = distance;
indices[orientation] = i - 1;
}
}, start, end);
// by default correct orientation (0) wins
// but if other one is really closer, return other one
if (mins[1] < mins[0] / 10.0) {
return indices[1];
} else {
return indices[0];
}
}
get len() {
return this.points.length / 2;
}
}
class Point {
constructor(lon, lat) {
this.lon = lon;
this.lat = lat;
}
coordinates(current_position, cos_direction, sin_direction) {
let translated = this.minus(current_position).times(40000.0);
let rotated_x = translated.lon * cos_direction - translated.lat * sin_direction;
let rotated_y = translated.lon * sin_direction + translated.lat * cos_direction;
return [
g.getWidth() / 2 - Math.round(rotated_x), // x is inverted
g.getHeight() / 2 + Math.round(rotated_y)
];
}
minus(other_point) {
let xdiff = this.lon - other_point.lon;
let ydiff = this.lat - other_point.lat;
return new Point(xdiff, ydiff);
}
plus(other_point) {
return new Point(this.lon + other_point.lon, this.lat + other_point.lat);
}
length_squared(other_point) {
let d = this.minus(other_point);
return (d.lon * d.lon + d.lat * d.lat);
}
times(scalar) {
return new Point(this.lon * scalar, this.lat * scalar);
}
dot(other_point) {
return this.lon * other_point.lon + this.lat * other_point.lat;
}
distance(other_point) {
//see https://www.movable-type.co.uk/scripts/latlong.html
const R = 6371e3; // metres
const phi1 = this.lat * Math.PI / 180;
const phi2 = other_point.lat * Math.PI / 180;
const deltaphi = (other_point.lat - this.lat) * Math.PI / 180;
const deltalambda = (other_point.lon - this.lon) * Math.PI / 180;
const a = Math.sin(deltaphi / 2) * Math.sin(deltaphi / 2) +
Math.cos(phi1) * Math.cos(phi2) *
Math.sin(deltalambda / 2) * Math.sin(deltalambda / 2);
const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
return R * c; // in metres
}
fake_distance(other_point) {
return Math.sqrt(this.length_squared(other_point));
}
fake_distance_to_segment(v, w) {
// from : https://stackoverflow.com/questions/849211/shortest-distance-between-a-point-and-a-line-segment
// Return minimum distance between line segment vw and point p
let l2 = v.length_squared(w); // i.e. |w-v|^2 - avoid a sqrt
if (l2 == 0.0) {
return this.distance(v); // v == w case
}
// Consider the line extending the segment, parameterized as v + t (w - v).
// We find projection of point p onto the line.
// It falls where t = [(p-v) . (w-v)] / |w-v|^2
// We clamp t from [0,1] to handle points outside the segment vw.
let t = Math.max(0, Math.min(1, (this.minus(v)).dot(w.minus(v)) / l2));
let projection = v.plus((w.minus(v)).times(t)); // Projection falls on the segment
return this.fake_distance(projection);
}
}
Bangle.loadWidgets();
let path = new Path("test.gpc");
let status = new Status(path);
let frame = 0;
let old_points = []; // remember the at most 3 previous points
function set_coordinates(data) {
frame += 1;
let valid_coordinates = !isNaN(data.lat) && !isNaN(data.lon);
if (valid_coordinates) {
// we try to figure out direction by looking at previous points
// instead of the gps course which is not very nice.
let direction = data.course * Math.PI / 180.0;
let position = new Point(data.lon, data.lat);
if (old_points.length == 0) {
old_points.push(position);
} else {
let last_point = old_points[old_points.length-1];
if (last_point.x != position.x || last_point.y != position.y) {
if (old_points.length == 4) {
old_points.shift();
}
old_points.push(position);
}
}
if (old_points.length == 4) {
// let's just take average angle of 3 previous segments
let angles_sum = 0;
for(let i = 0 ; i < 3 ; i++) {
let p1 = old_points[i];
let p2 = old_points[i+1];
let diff = p2.minus(p1);
let angle = Math.atan2(diff.lat, diff.lon);
angles_sum += angle;
}
status.update_position(position, angles_sum / 3.0);
} else {
status.update_position(position, direction);
}
}
let gps_status_color;
if ((frame % 2 == 0)||valid_coordinates) {
gps_status_color = g.theme.bg;
} else {
gps_status_color = g.theme.fg;
}
g.setColor(gps_status_color).setFont("6x8:2").drawString("gps", g.getWidth() - 40, 30);
}
let fake_gps_point = 0.0;
function simulate_gps(status) {
if (fake_gps_point > status.path.len -1) {
return;
}
let point_index = Math.floor(fake_gps_point);
if (point_index >= path.len) {
return;
}
let p1 = path.point(point_index);
let p2 = path.point(point_index + 1);
let alpha = fake_gps_point - point_index;
let pos = p1.times(1-alpha).plus(p2.times(alpha));
let old_pos = status.position;
fake_gps_point += 0.2; // advance simulation
let direction = Math.atan2(pos.lat - old_pos.lat, pos.lon - old_pos.lon);
status.update_position(pos, direction);
}
if (simulated) {
status.position = new Point(status.path.point(0));
setInterval(simulate_gps, 500, status);
} else {
// let's display start while waiting for gps signal
let p1 = status.path.point(0);
let p2 = status.path.point(1);
let diff = p2.minus(p1);
let direction = Math.atan2(diff.lat, diff.lon);
Bangle.setLocked(false);
status.update_position(p1, direction);
Bangle.setGPSPower(true, "gipy");
Bangle.on('GPS', set_coordinates);
}