gipy: jit is back

apps/gipy/ChangeLog

@@ -98,3 +98,6 @@
 	* New setting : power screen off between points to save battery
 	* Color change for lost direction (now purple)
 	* Adaptive screen powersaving
+
+0.21:
+	* Jit is back for display functions (10% speed increase)

apps/gipy/TODO

@@ -36,10 +36,20 @@ my conclusion is that:
 
 **************************
 
+JIT: array declaration in jit is buggy
+(especially several declarations)
+
+**************************
+
++ there is still a bug with negative remaining distances (when lost and nearest point is endpoint ?)
++ when lost we still get powersaving
++ try disabling gps for more powersaving
+
++ add heights
+
 + when you walk the direction still has a tendency to shift
 
 + put back foot only ways
-+ try fiddling with jit
 + put back street names
 + put back shortest paths but with points cache this time and jit
 + how to display paths from shortest path ?

apps/gipy/app.js

@@ -139,6 +139,19 @@ class TilesOffsets {
     }
 }
 
+// this function is not inlined to avoid array declaration in jit
+function center_points(points, scaled_current_x, scaled_current_y) {
+ return g.transformVertices(points, [1, 0, 0, 1, -scaled_current_x, -scaled_current_y]);
+}
+
+// this function is not inlined to avoid array declaration in jit
+function rotate_points(points, c, s) {
+  let center_x = g.getWidth() / 2;
+  let center_y = g.getHeight() / 2 + Y_OFFSET;
+
+  return g.transformVertices(points, [-c, s, s, c, center_x, center_y]);
+}
+
 class Map {
     constructor(buffer, offset, filename) {
         this.points_cache = []; // don't refetch points all the time
@@ -393,17 +406,12 @@ class Map {
         cos_direction,
         sin_direction
     ) {
-        // "jit";
-        let center_x = g.getWidth() / 2;
-        let center_y = g.getHeight() / 2 + Y_OFFSET;
-
+        "jit";
         let points = this.fetch_points(tile_x, tile_y, this.side * scale_factor);
         let scaled_current_x = current_x * scale_factor;
         let scaled_current_y = current_y * scale_factor;
-        let recentered_points = g.transformVertices(points, [1, 0, 0, 1, -scaled_current_x, -scaled_current_y]);
-        let c = cos_direction;
-        let s = sin_direction;
-        let screen_points = g.transformVertices(recentered_points, [-c, s, s, c, center_x, center_y]);
+        let recentered_points = center_points(points, scaled_current_x, scaled_current_y);
+        let screen_points = rotate_points(recentered_points, cos_direction, sin_direction);
 
         for (let i = 0; i < screen_points.length; i += 4) {
             g.drawLine(screen_points[i], screen_points[i + 1], screen_points[i + 2], screen_points[i + 3]);
@@ -419,17 +427,13 @@ class Map {
         cos_direction,
         sin_direction
     ) {
-        // "jit";
-        let center_x = g.getWidth() / 2;
-        let center_y = g.getHeight() / 2 + Y_OFFSET;
+        "jit";
 
         let points = this.fetch_points(tile_x, tile_y, this.side * scale_factor);
         let scaled_current_x = current_x * scale_factor;
         let scaled_current_y = current_y * scale_factor;
-        let recentered_points = g.transformVertices(points, [1, 0, 0, 1, -scaled_current_x, -scaled_current_y]);
-        let c = cos_direction;
-        let s = sin_direction;
-        let screen_points = g.transformVertices(recentered_points, [-c, s, s, c, center_x, center_y]);
+        let recentered_points = center_points(points, scaled_current_x, scaled_current_y);
+        let screen_points = rotate_points(recentered_points, cos_direction, sin_direction);
 
         for (let i = 0; i < screen_points.length; i += 4) {
             let final_x = screen_points[i];

apps/gipy/metadata.json

@@ -2,7 +2,7 @@
   "id": "gipy",
   "name": "Gipy",
   "shortName": "Gipy",
-  "version": "0.20",
+  "version": "0.21",
   "description": "Follow gpx files using the gps. Don't get lost in your bike trips and hikes.",
   "allow_emulator":false,
   "icon": "gipy.png",