From 056adb78732427b1d5bdee048bb770401c76e8a8 Mon Sep 17 00:00:00 2001
From: Martin Boonk <martin@boonk.info>
Date: Fri, 27 May 2022 10:53:52 +0200
Subject: [PATCH] Adds scaling to correct for linear mismatches in coordinates

---
 apps/calibration/app.js  | 87 +++++++++++++++++++++++++++++++---------
 apps/calibration/boot.js |  6 +--
 2 files changed, 70 insertions(+), 23 deletions(-)

diff --git a/apps/calibration/app.js b/apps/calibration/app.js
index 727a4c349..6227b936a 100644
--- a/apps/calibration/app.js
+++ b/apps/calibration/app.js
@@ -1,26 +1,24 @@
 class BanglejsApp {
   constructor() {
+    this.updateFactor = 0.2;
     this.x = 0;
     this.y = 0;
+    this.step = 0;
     this.settings = {
       xoffset: 0,
       yoffset: 0,
+      xscale: 1,
+      yscale: 1,
       };
   }
 
   load_settings() {
     let settings = require('Storage').readJSON('calibration.json', true) || {active: false};
 
-    // do nothing if the calibration is deactivated
-    if (settings.active === true) {
-      // cancel the calibration offset 
-      Bangle.on('touch', function(button, xy) {
-        xy.x += settings.xoffset;
-        xy.y += settings.yoffset;
-      });
-    }
     if (!settings.xoffset) settings.xoffset = 0;
     if (!settings.yoffset) settings.yoffset = 0;
+    if (!settings.xscale) settings.xscale = 1;
+    if (!settings.yscale) settings.yscale = 1;
 
     console.log('loaded settings:');
     console.log(settings);
@@ -46,19 +44,63 @@ class BanglejsApp {
   }
 
   drawTarget() {
-    this.x = 16 + Math.floor(Math.random() * (g.getWidth() - 32));
-    this.y = 40 + Math.floor(Math.random() * (g.getHeight() - 80));
+    switch (this.step){
+      case 0:
+        this.x = Math.floor(0.2 * g.getWidth());
+        this.y = Math.floor(0.2 * g.getHeight());
+        break;
+      case 1:
+        this.x = Math.floor(0.8 * g.getWidth());
+        this.y = Math.floor(0.2 * g.getHeight());
+        break;
+      case 2:
+        this.x = Math.floor(0.5 * g.getWidth());
+        this.y = Math.floor(0.5 * g.getHeight());
+        break;
+      case 3:
+        this.x = Math.floor(0.2 * g.getWidth());
+        this.y = Math.floor(0.8 * g.getHeight());
+        break;
+      case 4:
+        this.x = Math.floor(0.8 * g.getWidth());
+        this.y = Math.floor(0.8 * g.getHeight());
+        break;
+    }
 
-    g.clearRect(0, 0, g.getWidth(), g.getHeight());
+    g.setColor(g.theme.fg);
     g.drawLine(this.x, this.y - 5, this.x, this.y + 5);
     g.drawLine(this.x - 5, this.y, this.x + 5, this.y);
     g.setFont('Vector', 10);
-    g.drawString('current offset: ' + this.settings.xoffset + ', ' + this.settings.yoffset, 0, 24);
+    g.drawString('current offset: ' + this.settings.xoffset.toFixed(3) + ', ' + this.settings.yoffset.toFixed(3), 2, 2);
+    g.drawString('current scale: ' + this.settings.xscale.toFixed(3) + ', ' + this.settings.yscale.toFixed(3), 2, 12);
   }
-
+  
   setOffset(xy) {
-    this.settings.xoffset = Math.round((this.settings.xoffset + (this.x - Math.floor((this.x + xy.x)/2)))/2);
-    this.settings.yoffset = Math.round((this.settings.yoffset + (this.y - Math.floor((this.y + xy.y)/2)))/2);
+    this.last=xy;
+    switch (this.step){
+      case 0:
+        this.settings.xoffset = this.settings.xoffset * (1-this.updateFactor) + (this.x - xy.x) * this.updateFactor;
+        this.settings.yoffset = this.settings.yoffset * (1-this.updateFactor) + (this.y - xy.y) * this.updateFactor;
+        break;
+      case 1:
+        this.settings.xscale = this.settings.xscale * (1-this.updateFactor) + ((xy.x + this.settings.xoffset) / this.x) * this.updateFactor;
+        this.settings.yoffset = this.settings.yoffset * (1-this.updateFactor) + (this.y - xy.y) * this.updateFactor;
+        break;
+      case 3:
+        this.settings.xoffset = this.settings.xoffset * (1-this.updateFactor) + (this.x - xy.x) * this.updateFactor;
+        this.settings.yscale = this.settings.yscale * (1-this.updateFactor) + ((xy.y + this.settings.yoffset) / this.y) * this.updateFactor;
+        break;
+      case 2:
+      case 4:
+        this.settings.xscale = this.settings.xscale * (1-this.updateFactor) + ((xy.x + this.settings.xoffset) / this.x) * this.updateFactor;
+        this.settings.yscale = this.settings.yscale * (1-this.updateFactor) + ((xy.y + this.settings.yoffset) / this.y) * this.updateFactor;
+        break;
+    }
+  }
+  
+  nextStep() {
+    this.step++;
+    if ( this.step == 5 ) this.step = 0;
   }
 }
 
@@ -67,6 +109,14 @@ E.srand(Date.now());
 
 calibration = new BanglejsApp();
 calibration.load_settings();
+Bangle.disableCalibration = true;
+
+function touchHandler (btn, xy){
+  g.clearRect(0, 0, g.getWidth(), g.getHeight());
+  if (xy) calibration.setOffset(xy);
+  calibration.drawTarget();
+  calibration.nextStep();
+}
 
 let modes = {
   mode  : 'custom',
@@ -74,10 +124,7 @@ let modes = {
     calibration.save_settings(this.settings);
     load();
   },
-  touch : function(btn, xy) {
-    calibration.setOffset(xy);
-    calibration.drawTarget();
-  },
+  touch : touchHandler,
 };
 Bangle.setUI(modes);
-calibration.drawTarget();
+touchHandler();
diff --git a/apps/calibration/boot.js b/apps/calibration/boot.js
index 237fb2e0d..2c60de26b 100644
--- a/apps/calibration/boot.js
+++ b/apps/calibration/boot.js
@@ -1,7 +1,7 @@
 let cal_settings = require('Storage').readJSON("calibration.json", true) || {active: false};
 Bangle.on('touch', function(button, xy) {
   // do nothing if the calibration is deactivated
-  if (cal_settings.active === false) return;
+  if (cal_settings.active === false || Bangle.disableCalibration) return;
 
   // reload the calibration offset at each touch event /!\ bad for the flash memory
   if (cal_settings.reload === true) {
@@ -9,6 +9,6 @@ Bangle.on('touch', function(button, xy) {
   }
 
   // apply the calibration offset
-  xy.x += cal_settings.xoffset;
-  xy.y += cal_settings.yoffset;
+  xy.x = Math.round((xy.x + cal_settings.xoffset) * cal_settings.xscale);
+  xy.y = Math.round((xy.y + cal_settings.yoffset) * cal_settings.yscale);
 });