Added support for delta tower angle corrections.

Marlin/Conditionals_post.h

   #endif
 
   /**
-   * Delta radius/rod trimmers
+   * Delta radius/rod trimmers/angle trimmers
    */
   #if ENABLED(DELTA)
     #ifndef DELTA_RADIUS_TRIM_TOWER_1
     #ifndef DELTA_DIAGONAL_ROD_TRIM_TOWER_3
       #define DELTA_DIAGONAL_ROD_TRIM_TOWER_3 0.0
     #endif
+    #ifndef DELTA_TOWER_ANGLE_TRIM_1
+      #define DELTA_TOWER_ANGLE_TRIM_1 0.0
+    #endif
+    #ifndef DELTA_TOWER_ANGLE_TRIM_2
+      #define DELTA_TOWER_ANGLE_TRIM_2 0.0
+    #endif
+    #ifndef DELTA_TOWER_ANGLE_TRIM_3
+      #define DELTA_TOWER_ANGLE_TRIM_3 0.0
+    #endif
   #endif
 
   /**

Marlin/Marlin.h

                delta_diagonal_rod_trim_tower_1,
                delta_diagonal_rod_trim_tower_2,
                delta_diagonal_rod_trim_tower_3,
+               delta_tower_angle_trim_1,
+               delta_tower_angle_trim_2,
+               delta_tower_angle_trim_3,
                delta_clip_start_height;
   void recalc_delta_settings(float radius, float diagonal_rod);
 #elif IS_SCARA

Marlin/Marlin_main.cpp

 
   // these are the default values, can be overriden with M665
   float delta_radius = DELTA_RADIUS,
-        delta_tower1_x = -SIN_60 * (delta_radius + DELTA_RADIUS_TRIM_TOWER_1), // front left tower
-        delta_tower1_y = -COS_60 * (delta_radius + DELTA_RADIUS_TRIM_TOWER_1),
-        delta_tower2_x =  SIN_60 * (delta_radius + DELTA_RADIUS_TRIM_TOWER_2), // front right tower
-        delta_tower2_y = -COS_60 * (delta_radius + DELTA_RADIUS_TRIM_TOWER_2),
-        delta_tower3_x = 0,                                                    // back middle tower
-        delta_tower3_y = (delta_radius + DELTA_RADIUS_TRIM_TOWER_3),
+        delta_tower_angle_trim_1 = DELTA_TOWER_ANGLE_TRIM_1,
+        delta_tower_angle_trim_2 = DELTA_TOWER_ANGLE_TRIM_2,
+        delta_tower_angle_trim_3 = DELTA_TOWER_ANGLE_TRIM_3,
+        delta_tower1_x = -sin( (60 - delta_tower_angle_trim_1) * PI/180) * (delta_radius + DELTA_RADIUS_TRIM_TOWER_1), // front left tower
+        delta_tower1_y = -cos( (60 - delta_tower_angle_trim_1) * PI/180) * (delta_radius + DELTA_RADIUS_TRIM_TOWER_1),
+        delta_tower2_x =  sin( (60 + delta_tower_angle_trim_2) * PI/180) * (delta_radius + DELTA_RADIUS_TRIM_TOWER_2), // front right tower
+        delta_tower2_y = -cos( (60 + delta_tower_angle_trim_2) * PI/180) * (delta_radius + DELTA_RADIUS_TRIM_TOWER_2),
+        delta_tower3_x = -sin( (     delta_tower_angle_trim_3) * PI/180),                                                    // back middle tower
+        delta_tower3_y =  cos( (     delta_tower_angle_trim_3) * PI/180) * (delta_radius + DELTA_RADIUS_TRIM_TOWER_3),
         delta_diagonal_rod = DELTA_DIAGONAL_ROD,
         delta_diagonal_rod_trim_tower_1 = DELTA_DIAGONAL_ROD_TRIM_TOWER_1,
         delta_diagonal_rod_trim_tower_2 = DELTA_DIAGONAL_ROD_TRIM_TOWER_2,
     if (code_seen('A')) delta_diagonal_rod_trim_tower_1 = code_value_linear_units();
     if (code_seen('B')) delta_diagonal_rod_trim_tower_2 = code_value_linear_units();
     if (code_seen('C')) delta_diagonal_rod_trim_tower_3 = code_value_linear_units();
+    if (code_seen('I')) delta_tower_angle_trim_1 = code_value_linear_units();
+    if (code_seen('J')) delta_tower_angle_trim_2 = code_value_linear_units();
+    if (code_seen('K')) delta_tower_angle_trim_3 = code_value_linear_units();
     recalc_delta_settings(delta_radius, delta_diagonal_rod);
   }
   /**
    * settings have been changed (e.g., by M665).
    */
   void recalc_delta_settings(float radius, float diagonal_rod) {
-    delta_tower1_x = -SIN_60 * (radius + DELTA_RADIUS_TRIM_TOWER_1);  // front left tower
-    delta_tower1_y = -COS_60 * (radius + DELTA_RADIUS_TRIM_TOWER_1);
-    delta_tower2_x =  SIN_60 * (radius + DELTA_RADIUS_TRIM_TOWER_2);  // front right tower
-    delta_tower2_y = -COS_60 * (radius + DELTA_RADIUS_TRIM_TOWER_2);
-    delta_tower3_x = 0.0;                                             // back middle tower
-    delta_tower3_y = (radius + DELTA_RADIUS_TRIM_TOWER_3);
+    delta_tower1_x = -sin( (60 - delta_tower_angle_trim_1) * PI/180) * (delta_radius + DELTA_RADIUS_TRIM_TOWER_1), // front left tower
+    delta_tower1_y = -cos( (60 - delta_tower_angle_trim_1) * PI/180) * (delta_radius + DELTA_RADIUS_TRIM_TOWER_1),
+    delta_tower2_x =  sin( (60 + delta_tower_angle_trim_2) * PI/180) * (delta_radius + DELTA_RADIUS_TRIM_TOWER_2), // front right tower
+    delta_tower2_y = -cos( (60 + delta_tower_angle_trim_2) * PI/180) * (delta_radius + DELTA_RADIUS_TRIM_TOWER_2),
+    delta_tower3_x = -sin( (     delta_tower_angle_trim_3) * PI/180),                                              // back middle tower
+    delta_tower3_y =  cos( (     delta_tower_angle_trim_3) * PI/180) * (delta_radius + DELTA_RADIUS_TRIM_TOWER_3),
     delta_diagonal_rod_2_tower_1 = sq(diagonal_rod + delta_diagonal_rod_trim_tower_1);
     delta_diagonal_rod_2_tower_2 = sq(diagonal_rod + delta_diagonal_rod_trim_tower_2);
     delta_diagonal_rod_2_tower_3 = sq(diagonal_rod + delta_diagonal_rod_trim_tower_3);

Marlin/configuration_store.cpp

  *  308  G29 L F   bilinear_start                  (int x2)
  *  312            bed_level_grid[][]              (float x9, up to float x256) +988
  *
- * DELTA (if deltabot):                            36 bytes
+ * DELTA (if deltabot):                            48 bytes
  *  348  M666 XYZ  endstop_adj                     (float x3)
  *  360  M665 R    delta_radius                    (float)
  *  364  M665 L    delta_diagonal_rod              (float)
  *  372  M665 A    delta_diagonal_rod_trim_tower_1 (float)
  *  376  M665 B    delta_diagonal_rod_trim_tower_2 (float)
  *  380  M665 C    delta_diagonal_rod_trim_tower_3 (float)
+ *  384  M665 I    delta_tower_angle_trim_1        (float)
+ *  388  M665 J    delta_tower_angle_trim_2        (float)
+ *  392  M665 K    delta_tower_angle_trim_3        (float)
  *
  * Z_DUAL_ENDSTOPS:                                4 bytes
  *  384  M666 Z    z_endstop_adj                   (float)
       EEPROM_WRITE(delta_diagonal_rod_trim_tower_1);  // 1 float
       EEPROM_WRITE(delta_diagonal_rod_trim_tower_2);  // 1 float
       EEPROM_WRITE(delta_diagonal_rod_trim_tower_3);  // 1 float
+      EEPROM_WRITE(delta_tower_angle_trim_1); // 1 float
+      EEPROM_WRITE(delta_tower_angle_trim_2); // 1 float
+      EEPROM_WRITE(delta_tower_angle_trim_3); // 1 float
     #elif ENABLED(Z_DUAL_ENDSTOPS)
       EEPROM_WRITE(z_endstop_adj);            // 1 float
       dummy = 0.0f;
         EEPROM_READ(delta_diagonal_rod_trim_tower_1);  // 1 float
         EEPROM_READ(delta_diagonal_rod_trim_tower_2);  // 1 float
         EEPROM_READ(delta_diagonal_rod_trim_tower_3);  // 1 float
+        EEPROM_READ(delta_tower_angle_trim_1); // 1 float
+        EEPROM_READ(delta_tower_angle_trim_2); // 1 float
+        EEPROM_READ(delta_tower_angle_trim_3); // 1 float
       #elif ENABLED(Z_DUAL_ENDSTOPS)
         EEPROM_READ(z_endstop_adj);
         dummy = 0.0f;
     delta_diagonal_rod_trim_tower_1 = DELTA_DIAGONAL_ROD_TRIM_TOWER_1;
     delta_diagonal_rod_trim_tower_2 = DELTA_DIAGONAL_ROD_TRIM_TOWER_2;
     delta_diagonal_rod_trim_tower_3 = DELTA_DIAGONAL_ROD_TRIM_TOWER_3;
+    delta_tower_angle_trim_1 = DELTA_TOWER_ANGLE_TRIM_1;
+    delta_tower_angle_trim_2 = DELTA_TOWER_ANGLE_TRIM_2;
+    delta_tower_angle_trim_3 = DELTA_TOWER_ANGLE_TRIM_3;
   #elif ENABLED(Z_DUAL_ENDSTOPS)
     z_endstop_adj = 0;
   #endif
       SERIAL_EOL;
       CONFIG_ECHO_START;
       if (!forReplay) {
-        SERIAL_ECHOLNPGM("Delta settings: L=diagonal_rod, R=radius, S=segments_per_second, ABC=diagonal_rod_trim_tower_[123]");
+        SERIAL_ECHOLNPGM("Delta settings: L=diagonal_rod, R=radius, S=segments_per_second, ABC=diagonal_rod_trim_tower_[123], IJK=tower_angle_trim[123]");
         CONFIG_ECHO_START;
       }
       SERIAL_ECHOPAIR("  M665 L", delta_diagonal_rod);
       SERIAL_ECHOPAIR(" A", delta_diagonal_rod_trim_tower_1);
       SERIAL_ECHOPAIR(" B", delta_diagonal_rod_trim_tower_2);
       SERIAL_ECHOPAIR(" C", delta_diagonal_rod_trim_tower_3);
+      SERIAL_ECHOPAIR(" I", delta_tower_angle_trim_1);
+      SERIAL_ECHOPAIR(" J", delta_tower_angle_trim_2);
+      SERIAL_ECHOPAIR(" K", delta_tower_angle_trim_3);
       SERIAL_EOL;
     #elif ENABLED(Z_DUAL_ENDSTOPS)
       CONFIG_ECHO_START;