From b093b54598134b2cae450f5351150a601306b7f6 Mon Sep 17 00:00:00 2001
From: Julien Oculi <xdrz.jot.sr@gmail.com>
Date: Thu, 5 Jun 2025 11:05:36 +0200
Subject: [PATCH] feat: try implement roll correction for `maths`

---
 maths.cpp | 21 +++++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/maths.cpp b/maths.cpp
index 29afc02..5309b0d 100644
--- a/maths.cpp
+++ b/maths.cpp
@@ -20,6 +20,11 @@ void angleToStep(long &stepX, long &stepY, double angleX, double angleY) {
   stepY = angleY / stepRatioY;
 }
 
+double rollCorrection(double x, double max, double width) {
+  double correction = max * (1.0 - cos((10.0 * x) / (width * M_PI))) / 2.0;
+  return x - correction;
+}
+
 void cartesianToPolar(long &stepX, long &stepY, double zeroX, double zeroY, double x, double y, double z) {
   //TODO remove magic numbers
   double distance = 166.0; //turret to screen
@@ -28,12 +33,20 @@ void cartesianToPolar(long &stepX, long &stepY, double zeroX, double zeroY, doub
 
   x = -x; //natural axis direction
   double dX = x + offsetX;
-  double dY = y + offsetY;
+  double dY = rollCorrection(y + offsetY, 0.2, 400.0);
   double dZ = z + distance;
 
-  double rho = sqrt(pow(dX, 2.0) + pow(dY, 2.0) + pow(dZ, 2.0));
-  double angleY = M_PI / 2.0 - acos(dY / rho);
-  double angleX = atan2(dX, dZ);
+
+  double roll = atan2(4.0, 236.0);
+  double rollY = dX * tan(roll);
+  double rollX = dY * tan(roll);
+
+  double dXr = dX + rollX;
+  double dYr = dY + rollY;
+  
+  double rho = sqrt(pow(dXr, 2.0) + pow(dYr, 2.0) + pow(dZ, 2.0));
+  double angleY = M_PI / 2.0 - acos(dYr / rho);
+  double angleX = atan2(dXr, dZ);
 
   angleToStep(stepX, stepY, angleX, angleY);    
 }