/**
   * G26: Mesh Validation Pattern generation.
   *
   * Used to interactively edit UBL's Mesh by placing the
   * nozzle in a problem area and doing a G29 P4 R command.
   */
  void unified_bed_leveling::G26() {
    SERIAL_ECHOLNPGM("G26 command started.  Waiting for heater(s).");
    float tmp, start_angle, end_angle;
    int   i, xi, yi;
    mesh_index_pair location;

    // Don't allow Mesh Validation without homing first,
    // or if the parameter parsing did not go OK, abort
    if (axis_unhomed_error() || parse_G26_parameters()) return;

    if (current_position[Z_AXIS] < Z_CLEARANCE_BETWEEN_PROBES) {
      do_blocking_move_to_z(Z_CLEARANCE_BETWEEN_PROBES);
      stepper.synchronize();
      set_current_to_destination();
    }

    if (turn_on_heaters()) goto LEAVE;

    current_position[E_AXIS] = 0.0;
    sync_plan_position_e();

    if (g26_prime_flag && prime_nozzle()) goto LEAVE;

    /**
     *  Bed is preheated
     *
     *  Nozzle is at temperature
     *
     *  Filament is primed!
     *
     *  It's  "Show Time" !!!
     */

    ZERO(circle_flags);
    ZERO(horizontal_mesh_line_flags);
    ZERO(vertical_mesh_line_flags);

    // Move nozzle to the specified height for the first layer
    set_destination_to_current();
    destination[Z_AXIS] = g26_layer_height;
    move_to(destination, 0.0);
    move_to(destination, g26_ooze_amount);

    has_control_of_lcd_panel = true;
    //debug_current_and_destination(PSTR("Starting G26 Mesh Validation Pattern."));

    /**
     * Declare and generate a sin() & cos() table to be used during the circle drawing.  This will lighten
     * the CPU load and make the arc drawing faster and more smooth
     */
    float sin_table[360 / 30 + 1], cos_table[360 / 30 + 1];
    for (i = 0; i <= 360 / 30; i++) {
      cos_table[i] = SIZE_OF_INTERSECTION_CIRCLES * cos(RADIANS(valid_trig_angle(i * 30.0)));
      sin_table[i] = SIZE_OF_INTERSECTION_CIRCLES * sin(RADIANS(valid_trig_angle(i * 30.0)));
    }

    do {
      location = g26_continue_with_closest
        ? find_closest_circle_to_print(current_position[X_AXIS], current_position[Y_AXIS])
        : find_closest_circle_to_print(g26_x_pos, g26_y_pos); // Find the closest Mesh Intersection to where we are now.

      if (location.x_index >= 0 && location.y_index >= 0) {
        const float circle_x = mesh_index_to_xpos(location.x_index),
                    circle_y = mesh_index_to_ypos(location.y_index);

        // If this mesh location is outside the printable_radius, skip it.

        if (!position_is_reachable_raw_xy(circle_x, circle_y)) continue;

        xi = location.x_index;  // Just to shrink the next few lines and make them easier to understand
        yi = location.y_index;

        if (g26_debug_flag) {
          SERIAL_ECHOPAIR("   Doing circle at: (xi=", xi);
          SERIAL_ECHOPAIR(", yi=", yi);
          SERIAL_CHAR(')');
          SERIAL_EOL();
        }

        start_angle = 0.0;    // assume it is going to be a full circle
        end_angle   = 360.0;
        if (xi == 0) {       // Check for bottom edge
          start_angle = -90.0;
          end_angle   =  90.0;
          if (yi == 0)        // it is an edge, check for the two left corners
            start_angle = 0.0;
          else if (yi == GRID_MAX_POINTS_Y - 1)
            end_angle = 0.0;
        }
        else if (xi == GRID_MAX_POINTS_X - 1) { // Check for top edge
          start_angle =  90.0;
          end_angle   = 270.0;
          if (yi == 0)                  // it is an edge, check for the two right corners
            end_angle = 180.0;
          else if (yi == GRID_MAX_POINTS_Y - 1)
            start_angle = 180.0;
        }
        else if (yi == 0) {
          start_angle =   0.0;         // only do the top   side of the cirlce
          end_angle   = 180.0;
        }
        else if (yi == GRID_MAX_POINTS_Y - 1) {
          start_angle = 180.0;         // only do the bottom side of the cirlce
          end_angle   = 360.0;
        }

        for (tmp = start_angle; tmp < end_angle - 0.1; tmp += 30.0) {

          #if ENABLED(NEWPANEL)
            if (user_canceled()) goto LEAVE;              // Check if the user wants to stop the Mesh Validation
          #endif

          int tmp_div_30 = tmp / 30.0;
          if (tmp_div_30 < 0) tmp_div_30 += 360 / 30;
          if (tmp_div_30 > 11) tmp_div_30 -= 360 / 30;

          float x = circle_x + cos_table[tmp_div_30],    // for speed, these are now a lookup table entry
                y = circle_y + sin_table[tmp_div_30],
                xe = circle_x + cos_table[tmp_div_30 + 1],
                ye = circle_y + sin_table[tmp_div_30 + 1];
          #if IS_KINEMATIC
            // Check to make sure this segment is entirely on the bed, skip if not.
            if (!position_is_reachable_raw_xy(x, y) || !position_is_reachable_raw_xy(xe, ye)) continue;
          #else                                              // not, we need to skip
            x  = constrain(x, X_MIN_POS + 1, X_MAX_POS - 1); // This keeps us from bumping the endstops
            y  = constrain(y, Y_MIN_POS + 1, Y_MAX_POS - 1);
            xe = constrain(xe, X_MIN_POS + 1, X_MAX_POS - 1);
            ye = constrain(ye, Y_MIN_POS + 1, Y_MAX_POS - 1);
          #endif

          //if (g26_debug_flag) {
          //  char ccc, *cptr, seg_msg[50], seg_num[10];
          //  strcpy(seg_msg, "   segment: ");
          //  strcpy(seg_num, "    \n");
          //  cptr = (char*) "01234567890ABCDEF????????";
          //  ccc = cptr[tmp_div_30];
          //  seg_num[1] = ccc;
          //  strcat(seg_msg, seg_num);
          //  debug_current_and_destination(seg_msg);
          //}

          print_line_from_here_to_there(LOGICAL_X_POSITION(x), LOGICAL_Y_POSITION(y), g26_layer_height, LOGICAL_X_POSITION(xe), LOGICAL_Y_POSITION(ye), g26_layer_height);

        }
        if (look_for_lines_to_connect())
          goto LEAVE;
      }
    } while (--g26_repeats && location.x_index >= 0 && location.y_index >= 0);

    LEAVE:
    lcd_setstatusPGM(PSTR("Leaving G26"), -1);

    retract_filament(destination);
    destination[Z_AXIS] = Z_CLEARANCE_BETWEEN_PROBES;

    //debug_current_and_destination(PSTR("ready to do Z-Raise."));
    move_to(destination, 0); // Raise the nozzle
    //debug_current_and_destination(PSTR("done doing Z-Raise."));

    destination[X_AXIS] = g26_x_pos;                                               // Move back to the starting position
    destination[Y_AXIS] = g26_y_pos;
    //destination[Z_AXIS] = Z_CLEARANCE_BETWEEN_PROBES;                        // Keep the nozzle where it is

    move_to(destination, 0); // Move back to the starting position
    //debug_current_and_destination(PSTR("done doing X/Y move."));

    has_control_of_lcd_panel = false;     // Give back control of the LCD Panel!

    if (!g26_keep_heaters_on) {
      #if HAS_TEMP_BED
        thermalManager.setTargetBed(0);
      #endif
      thermalManager.setTargetHotend(0, 0);
    }
  }
Esempio n. 2
0
/**
 * G26: Mesh Validation Pattern generation.
 *
 * Used to interactively edit the mesh by placing the
 * nozzle in a problem area and doing a G29 P4 R command.
 *
 * Parameters:
 *
 *  B  Bed Temperature
 *  C  Continue from the Closest mesh point
 *  D  Disable leveling before starting
 *  F  Filament diameter
 *  H  Hotend Temperature
 *  K  Keep heaters on when completed
 *  L  Layer Height
 *  O  Ooze extrusion length
 *  P  Prime length
 *  Q  Retraction multiplier
 *  R  Repetitions (number of grid points)
 *  S  Nozzle Size (diameter) in mm
 *  T  Tool index to change to, if included
 *  U  Random deviation (50 if no value given)
 *  X  X position
 *  Y  Y position
 */
void GcodeSuite::G26() {
  SERIAL_ECHOLNPGM("G26 starting...");

  // Don't allow Mesh Validation without homing first,
  // or if the parameter parsing did not go OK, abort
  if (axis_unhomed_error()) return;

  // Change the tool first, if specified
  if (parser.seenval('T')) tool_change(parser.value_int());

  g26_extrusion_multiplier    = EXTRUSION_MULTIPLIER;
  g26_retraction_multiplier   = RETRACTION_MULTIPLIER;
  g26_layer_height            = MESH_TEST_LAYER_HEIGHT;
  g26_prime_length            = PRIME_LENGTH;
  g26_bed_temp                = MESH_TEST_BED_TEMP;
  g26_hotend_temp             = MESH_TEST_HOTEND_TEMP;
  g26_prime_flag              = 0;

  float g26_nozzle            = MESH_TEST_NOZZLE_SIZE,
        g26_filament_diameter = DEFAULT_NOMINAL_FILAMENT_DIA,
        g26_ooze_amount       = parser.linearval('O', OOZE_AMOUNT);

  bool g26_continue_with_closest = parser.boolval('C'),
       g26_keep_heaters_on       = parser.boolval('K');

  if (parser.seenval('B')) {
    g26_bed_temp = parser.value_celsius();
    if (g26_bed_temp && !WITHIN(g26_bed_temp, 40, 140)) {
      SERIAL_ECHOLNPGM("?Specified bed temperature not plausible (40-140C).");
      return;
    }
  }

  if (parser.seenval('L')) {
    g26_layer_height = parser.value_linear_units();
    if (!WITHIN(g26_layer_height, 0.0, 2.0)) {
      SERIAL_ECHOLNPGM("?Specified layer height not plausible.");
      return;
    }
  }

  if (parser.seen('Q')) {
    if (parser.has_value()) {
      g26_retraction_multiplier = parser.value_float();
      if (!WITHIN(g26_retraction_multiplier, 0.05, 15.0)) {
        SERIAL_ECHOLNPGM("?Specified Retraction Multiplier not plausible.");
        return;
      }
    }
    else {
      SERIAL_ECHOLNPGM("?Retraction Multiplier must be specified.");
      return;
    }
  }

  if (parser.seenval('S')) {
    g26_nozzle = parser.value_float();
    if (!WITHIN(g26_nozzle, 0.1, 1.0)) {
      SERIAL_ECHOLNPGM("?Specified nozzle size not plausible.");
      return;
    }
  }

  if (parser.seen('P')) {
    if (!parser.has_value()) {
      #if HAS_LCD_MENU
        g26_prime_flag = -1;
      #else
        SERIAL_ECHOLNPGM("?Prime length must be specified when not using an LCD.");
        return;
      #endif
    }
    else {
      g26_prime_flag++;
      g26_prime_length = parser.value_linear_units();
      if (!WITHIN(g26_prime_length, 0.0, 25.0)) {
        SERIAL_ECHOLNPGM("?Specified prime length not plausible.");
        return;
      }
    }
  }

  if (parser.seenval('F')) {
    g26_filament_diameter = parser.value_linear_units();
    if (!WITHIN(g26_filament_diameter, 1.0, 4.0)) {
      SERIAL_ECHOLNPGM("?Specified filament size not plausible.");
      return;
    }
  }
  g26_extrusion_multiplier *= sq(1.75) / sq(g26_filament_diameter); // If we aren't using 1.75mm filament, we need to
                                                                    // scale up or down the length needed to get the
                                                                    // same volume of filament

  g26_extrusion_multiplier *= g26_filament_diameter * sq(g26_nozzle) / sq(0.3); // Scale up by nozzle size

  if (parser.seenval('H')) {
    g26_hotend_temp = parser.value_celsius();
    if (!WITHIN(g26_hotend_temp, 165, 280)) {
      SERIAL_ECHOLNPGM("?Specified nozzle temperature not plausible.");
      return;
    }
  }

  if (parser.seen('U')) {
    randomSeed(millis());
    // This setting will persist for the next G26
    random_deviation = parser.has_value() ? parser.value_float() : 50.0;
  }

  int16_t g26_repeats;
  #if HAS_LCD_MENU
    g26_repeats = parser.intval('R', GRID_MAX_POINTS + 1);
  #else
    if (!parser.seen('R')) {
      SERIAL_ECHOLNPGM("?(R)epeat must be specified when not using an LCD.");
      return;
    }
    else
      g26_repeats = parser.has_value() ? parser.value_int() : GRID_MAX_POINTS + 1;
  #endif
  if (g26_repeats < 1) {
    SERIAL_ECHOLNPGM("?(R)epeat value not plausible; must be at least 1.");
    return;
  }

  g26_x_pos = parser.seenval('X') ? RAW_X_POSITION(parser.value_linear_units()) : current_position[X_AXIS];
  g26_y_pos = parser.seenval('Y') ? RAW_Y_POSITION(parser.value_linear_units()) : current_position[Y_AXIS];
  if (!position_is_reachable(g26_x_pos, g26_y_pos)) {
    SERIAL_ECHOLNPGM("?Specified X,Y coordinate out of bounds.");
    return;
  }

  /**
   * Wait until all parameters are verified before altering the state!
   */
  set_bed_leveling_enabled(!parser.seen('D'));

  if (current_position[Z_AXIS] < Z_CLEARANCE_BETWEEN_PROBES) {
    do_blocking_move_to_z(Z_CLEARANCE_BETWEEN_PROBES);
    set_current_from_destination();
  }

  if (turn_on_heaters() != G26_OK) goto LEAVE;

  current_position[E_AXIS] = 0.0;
  sync_plan_position_e();

  if (g26_prime_flag && prime_nozzle() != G26_OK) goto LEAVE;

  /**
   *  Bed is preheated
   *
   *  Nozzle is at temperature
   *
   *  Filament is primed!
   *
   *  It's  "Show Time" !!!
   */

  ZERO(circle_flags);
  ZERO(horizontal_mesh_line_flags);
  ZERO(vertical_mesh_line_flags);

  // Move nozzle to the specified height for the first layer
  set_destination_from_current();
  destination[Z_AXIS] = g26_layer_height;
  move_to(destination, 0.0);
  move_to(destination, g26_ooze_amount);

  #if HAS_LCD_MENU
    ui.capture();
  #endif

  //debug_current_and_destination(PSTR("Starting G26 Mesh Validation Pattern."));

  #if DISABLED(ARC_SUPPORT)

    /**
     * Pre-generate radius offset values at 30 degree intervals to reduce CPU load.
     */
    #define A_INT 30
    #define _ANGS (360 / A_INT)
    #define A_CNT (_ANGS / 2)
    #define _IND(A) ((A + _ANGS * 8) % _ANGS)
    #define _COS(A) (trig_table[_IND(A) % A_CNT] * (_IND(A) >= A_CNT ? -1 : 1))
    #define _SIN(A) (-_COS((A + A_CNT / 2) % _ANGS))
    #if A_CNT & 1
      #error "A_CNT must be a positive value. Please change A_INT."
    #endif
    float trig_table[A_CNT];
    for (uint8_t i = 0; i < A_CNT; i++)
      trig_table[i] = INTERSECTION_CIRCLE_RADIUS * cos(RADIANS(i * A_INT));

  #endif // !ARC_SUPPORT

  mesh_index_pair location;
  do {
     location = g26_continue_with_closest
      ? find_closest_circle_to_print(current_position[X_AXIS], current_position[Y_AXIS])
      : find_closest_circle_to_print(g26_x_pos, g26_y_pos); // Find the closest Mesh Intersection to where we are now.

    if (location.x_index >= 0 && location.y_index >= 0) {
      const float circle_x = _GET_MESH_X(location.x_index),
                  circle_y = _GET_MESH_Y(location.y_index);

      // If this mesh location is outside the printable_radius, skip it.
      if (!position_is_reachable(circle_x, circle_y)) continue;

      // Determine where to start and end the circle,
      // which is always drawn counter-clockwise.
      const uint8_t xi = location.x_index, yi = location.y_index;
      const bool f = yi == 0, r = xi >= GRID_MAX_POINTS_X - 1, b = yi >= GRID_MAX_POINTS_Y - 1;

      #if ENABLED(ARC_SUPPORT)

        #define ARC_LENGTH(quarters)  (INTERSECTION_CIRCLE_RADIUS * M_PI * (quarters) / 2)
        float sx = circle_x + INTERSECTION_CIRCLE_RADIUS,   // default to full circle
              ex = circle_x + INTERSECTION_CIRCLE_RADIUS,
              sy = circle_y, ey = circle_y,
              arc_length = ARC_LENGTH(4);

        // Figure out where to start and end the arc - we always print counterclockwise
        if (xi == 0) {                             // left edge
          sx = f ? circle_x + INTERSECTION_CIRCLE_RADIUS : circle_x;
          ex = b ? circle_x + INTERSECTION_CIRCLE_RADIUS : circle_x;
          sy = f ? circle_y : circle_y - (INTERSECTION_CIRCLE_RADIUS);
          ey = b ? circle_y : circle_y + INTERSECTION_CIRCLE_RADIUS;
          arc_length = (f || b) ? ARC_LENGTH(1) : ARC_LENGTH(2);
        }
        else if (r) {                             // right edge
          sx = b ? circle_x - (INTERSECTION_CIRCLE_RADIUS) : circle_x;
          ex = f ? circle_x - (INTERSECTION_CIRCLE_RADIUS) : circle_x;
          sy = b ? circle_y : circle_y + INTERSECTION_CIRCLE_RADIUS;
          ey = f ? circle_y : circle_y - (INTERSECTION_CIRCLE_RADIUS);
          arc_length = (f || b) ? ARC_LENGTH(1) : ARC_LENGTH(2);
        }
        else if (f) {
          sx = circle_x + INTERSECTION_CIRCLE_RADIUS;
          ex = circle_x - (INTERSECTION_CIRCLE_RADIUS);
          sy = ey = circle_y;
          arc_length = ARC_LENGTH(2);
        }
        else if (b) {
          sx = circle_x - (INTERSECTION_CIRCLE_RADIUS);
          ex = circle_x + INTERSECTION_CIRCLE_RADIUS;
          sy = ey = circle_y;
          arc_length = ARC_LENGTH(2);
        }
        const float arc_offset[2] = {
          circle_x - sx,
          circle_y - sy
        };

        const float dx_s = current_position[X_AXIS] - sx,   // find our distance from the start of the actual circle
                    dy_s = current_position[Y_AXIS] - sy,
                    dist_start = HYPOT2(dx_s, dy_s);
        const float endpoint[XYZE] = {
          ex, ey,
          g26_layer_height,
          current_position[E_AXIS] + (arc_length * g26_e_axis_feedrate * g26_extrusion_multiplier)
        };

        if (dist_start > 2.0) {
          retract_filament(destination);
          //todo:  parameterize the bump height with a define
          move_to(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS] + 0.500, 0.0);  // Z bump to minimize scraping
          move_to(sx, sy, g26_layer_height + 0.500, 0.0); // Get to the starting point with no extrusion while bumped
        }

        move_to(sx, sy, g26_layer_height, 0.0); // Get to the starting point with no extrusion / un-Z bump

        recover_filament(destination);
        const float save_feedrate = feedrate_mm_s;
        feedrate_mm_s = PLANNER_XY_FEEDRATE() / 10.0;

        if (g26_debug_flag) {
          SERIAL_ECHOPAIR(" plan_arc(ex=", endpoint[X_AXIS]);
          SERIAL_ECHOPAIR(", ey=", endpoint[Y_AXIS]);
          SERIAL_ECHOPAIR(", ez=", endpoint[Z_AXIS]);
          SERIAL_ECHOPAIR(", len=", arc_length);
          SERIAL_ECHOPAIR(") -> (ex=", current_position[X_AXIS]);
          SERIAL_ECHOPAIR(", ey=", current_position[Y_AXIS]);
          SERIAL_ECHOPAIR(", ez=", current_position[Z_AXIS]);
          SERIAL_CHAR(')');
          SERIAL_EOL();
        }

        plan_arc(endpoint, arc_offset, false);  // Draw a counter-clockwise arc
        feedrate_mm_s = save_feedrate;
        set_destination_from_current();
        #if HAS_LCD_MENU
          if (user_canceled()) goto LEAVE; // Check if the user wants to stop the Mesh Validation
        #endif

      #else // !ARC_SUPPORT

        int8_t start_ind = -2, end_ind = 9; // Assume a full circle (from 5:00 to 5:00)
        if (xi == 0) {                      // Left edge? Just right half.
          start_ind = f ? 0 : -3;           //  03:00 to 12:00 for front-left
          end_ind = b ? 0 : 2;              //  06:00 to 03:00 for back-left
        }
        else if (r) {                       // Right edge? Just left half.
          start_ind = b ? 6 : 3;            //  12:00 to 09:00 for front-right
          end_ind = f ? 5 : 8;              //  09:00 to 06:00 for back-right
        }
        else if (f) {                       // Front edge? Just back half.
          start_ind = 0;                    //  03:00
          end_ind = 5;                      //  09:00
        }
        else if (b) {                       // Back edge? Just front half.
          start_ind = 6;                    //  09:00
          end_ind = 11;                     //  03:00
        }

        for (int8_t ind = start_ind; ind <= end_ind; ind++) {

          #if HAS_LCD_MENU
            if (user_canceled()) goto LEAVE;          // Check if the user wants to stop the Mesh Validation
          #endif

          float rx = circle_x + _COS(ind),            // For speed, these are now a lookup table entry
                ry = circle_y + _SIN(ind),
                xe = circle_x + _COS(ind + 1),
                ye = circle_y + _SIN(ind + 1);

          #if IS_KINEMATIC
            // Check to make sure this segment is entirely on the bed, skip if not.
            if (!position_is_reachable(rx, ry) || !position_is_reachable(xe, ye)) continue;
          #else                                               // not, we need to skip
            rx = constrain(rx, X_MIN_POS + 1, X_MAX_POS - 1); // This keeps us from bumping the endstops
            ry = constrain(ry, Y_MIN_POS + 1, Y_MAX_POS - 1);
            xe = constrain(xe, X_MIN_POS + 1, X_MAX_POS - 1);
            ye = constrain(ye, Y_MIN_POS + 1, Y_MAX_POS - 1);
          #endif

          print_line_from_here_to_there(rx, ry, g26_layer_height, xe, ye, g26_layer_height);
          SERIAL_FLUSH();  // Prevent host M105 buffer overrun.
        }

      #endif // !ARC_SUPPORT

      if (look_for_lines_to_connect()) goto LEAVE;
    }

    SERIAL_FLUSH(); // Prevent host M105 buffer overrun.

  } while (--g26_repeats && location.x_index >= 0 && location.y_index >= 0);

  LEAVE:
  ui.set_status_P(PSTR("Leaving G26"), -1);

  retract_filament(destination);
  destination[Z_AXIS] = Z_CLEARANCE_BETWEEN_PROBES;

  //debug_current_and_destination(PSTR("ready to do Z-Raise."));
  move_to(destination, 0); // Raise the nozzle
  //debug_current_and_destination(PSTR("done doing Z-Raise."));

  destination[X_AXIS] = g26_x_pos;                            // Move back to the starting position
  destination[Y_AXIS] = g26_y_pos;
  //destination[Z_AXIS] = Z_CLEARANCE_BETWEEN_PROBES;         // Keep the nozzle where it is

  move_to(destination, 0);                                    // Move back to the starting position
  //debug_current_and_destination(PSTR("done doing X/Y move."));

  #if HAS_LCD_MENU
    ui.release();                                             // Give back control of the LCD
  #endif

  if (!g26_keep_heaters_on) {
    #if HAS_HEATED_BED
      thermalManager.setTargetBed(0);
    #endif
    thermalManager.setTargetHotend(active_extruder, 0);
  }
}
  /**
   * G26: Mesh Validation Pattern generation.
   *
   * Used to interactively edit UBL's Mesh by placing the
   * nozzle in a problem area and doing a G29 P4 R command.
   */
  void gcode_G26() {
    SERIAL_ECHOLNPGM("G26 command started.  Waiting for heater(s).");
    float tmp, start_angle, end_angle;
    int   i, xi, yi;
    mesh_index_pair location;

    // Don't allow Mesh Validation without homing first,
    // or if the parameter parsing did not go OK, abort
    if (axis_unhomed_error(true, true, true) || parse_G26_parameters()) return;

    if (current_position[Z_AXIS] < Z_CLEARANCE_BETWEEN_PROBES) {
      do_blocking_move_to_z(Z_CLEARANCE_BETWEEN_PROBES);
      stepper.synchronize();
      set_current_to_destination();
    }

    if (turn_on_heaters()) goto LEAVE;

    current_position[E_AXIS] = 0.0;
    sync_plan_position_e();

    if (prime_flag && prime_nozzle()) goto LEAVE;

    /**
     *  Bed is preheated
     *
     *  Nozzle is at temperature
     *
     *  Filament is primed!
     *
     *  It's  "Show Time" !!!
     */

    ZERO(circle_flags);
    ZERO(horizontal_mesh_line_flags);
    ZERO(vertical_mesh_line_flags);

    // Move nozzle to the specified height for the first layer
    set_destination_to_current();
    destination[Z_AXIS] = layer_height;
    move_to(destination[X_AXIS], destination[Y_AXIS], destination[Z_AXIS], 0.0);
    move_to(destination[X_AXIS], destination[Y_AXIS], destination[Z_AXIS], ooze_amount);

    ubl.has_control_of_lcd_panel = true;
    //debug_current_and_destination(PSTR("Starting G26 Mesh Validation Pattern."));

    /**
     * Declare and generate a sin() & cos() table to be used during the circle drawing.  This will lighten
     * the CPU load and make the arc drawing faster and more smooth
     */
    float sin_table[360 / 30 + 1], cos_table[360 / 30 + 1];
    for (i = 0; i <= 360 / 30; i++) {
      cos_table[i] = SIZE_OF_INTERSECTION_CIRCLES * cos(RADIANS(valid_trig_angle(i * 30.0)));
      sin_table[i] = SIZE_OF_INTERSECTION_CIRCLES * sin(RADIANS(valid_trig_angle(i * 30.0)));
    }

    do {

      if (ubl_lcd_clicked()) {              // Check if the user wants to stop the Mesh Validation
        #if ENABLED(ULTRA_LCD)
          lcd_setstatuspgm(PSTR("Mesh Validation Stopped."), 99);
          lcd_quick_feedback();
        #endif
        while (!ubl_lcd_clicked()) {         // Wait until the user is done pressing the
          idle();                            // Encoder Wheel if that is why we are leaving
          lcd_reset_alert_level();
          lcd_setstatuspgm(PSTR(""));
        }
        while (ubl_lcd_clicked()) {          // Wait until the user is done pressing the
          idle();                            // Encoder Wheel if that is why we are leaving
          lcd_setstatuspgm(PSTR("Unpress Wheel"), 99);
        }
        goto LEAVE;
      }

      location = continue_with_closest
        ? find_closest_circle_to_print(current_position[X_AXIS], current_position[Y_AXIS])
        : find_closest_circle_to_print(x_pos, y_pos); // Find the closest Mesh Intersection to where we are now.

      if (location.x_index >= 0 && location.y_index >= 0) {
        const float circle_x = pgm_read_float(&ubl.mesh_index_to_xpos[location.x_index]),
                    circle_y = pgm_read_float(&ubl.mesh_index_to_ypos[location.y_index]);

        // Let's do a couple of quick sanity checks.  We can pull this code out later if we never see it catch a problem
        #ifdef DELTA
          if (HYPOT2(circle_x, circle_y) > sq(DELTA_PRINTABLE_RADIUS)) {
            SERIAL_ERROR_START;
            SERIAL_ERRORLNPGM("Attempt to print outside of DELTA_PRINTABLE_RADIUS.");
            goto LEAVE;
          }
        #endif

        // TODO: Change this to use `position_is_reachable`
        if (!WITHIN(circle_x, X_MIN_POS, X_MAX_POS) || !WITHIN(circle_y, Y_MIN_POS, Y_MAX_POS)) {
          SERIAL_ERROR_START;
          SERIAL_ERRORLNPGM("Attempt to print off the bed.");
          goto LEAVE;
        }

        xi = location.x_index;  // Just to shrink the next few lines and make them easier to understand
        yi = location.y_index;

        if (ubl.g26_debug_flag) {
          SERIAL_ECHOPAIR("   Doing circle at: (xi=", xi);
          SERIAL_ECHOPAIR(", yi=", yi);
          SERIAL_CHAR(')');
          SERIAL_EOL;
        }

        start_angle = 0.0;    // assume it is going to be a full circle
        end_angle   = 360.0;
        if (xi == 0) {       // Check for bottom edge
          start_angle = -90.0;
          end_angle   =  90.0;
          if (yi == 0)        // it is an edge, check for the two left corners
            start_angle = 0.0;
          else if (yi == GRID_MAX_POINTS_Y - 1)
            end_angle = 0.0;
        }
        else if (xi == GRID_MAX_POINTS_X - 1) { // Check for top edge
          start_angle =  90.0;
          end_angle   = 270.0;
          if (yi == 0)                  // it is an edge, check for the two right corners
            end_angle = 180.0;
          else if (yi == GRID_MAX_POINTS_Y - 1)
            start_angle = 180.0;
        }
        else if (yi == 0) {
          start_angle =   0.0;         // only do the top   side of the cirlce
          end_angle   = 180.0;
        }
        else if (yi == GRID_MAX_POINTS_Y - 1) {
          start_angle = 180.0;         // only do the bottom side of the cirlce
          end_angle   = 360.0;
        }

        for (tmp = start_angle; tmp < end_angle - 0.1; tmp += 30.0) {
          int tmp_div_30 = tmp / 30.0;
          if (tmp_div_30 < 0) tmp_div_30 += 360 / 30;
          if (tmp_div_30 > 11) tmp_div_30 -= 360 / 30;

          float x = circle_x + cos_table[tmp_div_30],    // for speed, these are now a lookup table entry
                y = circle_y + sin_table[tmp_div_30],
                xe = circle_x + cos_table[tmp_div_30 + 1],
                ye = circle_y + sin_table[tmp_div_30 + 1];
          #ifdef DELTA
            if (HYPOT2(x, y) > sq(DELTA_PRINTABLE_RADIUS))   // Check to make sure this part of
              continue;                                      // the 'circle' is on the bed.  If
          #else                                              // not, we need to skip
            x  = constrain(x, X_MIN_POS + 1, X_MAX_POS - 1); // This keeps us from bumping the endstops
            y  = constrain(y, Y_MIN_POS + 1, Y_MAX_POS - 1);
            xe = constrain(xe, X_MIN_POS + 1, X_MAX_POS - 1);
            ye = constrain(ye, Y_MIN_POS + 1, Y_MAX_POS - 1);
          #endif

          //if (ubl.g26_debug_flag) {
          //  char ccc, *cptr, seg_msg[50], seg_num[10];
          //  strcpy(seg_msg, "   segment: ");
          //  strcpy(seg_num, "    \n");
          //  cptr = (char*) "01234567890ABCDEF????????";
          //  ccc = cptr[tmp_div_30];
          //  seg_num[1] = ccc;
          //  strcat(seg_msg, seg_num);
          //  debug_current_and_destination(seg_msg);
          //}

          print_line_from_here_to_there(LOGICAL_X_POSITION(x), LOGICAL_Y_POSITION(y), layer_height, LOGICAL_X_POSITION(xe), LOGICAL_Y_POSITION(ye), layer_height);

        }

        //debug_current_and_destination(PSTR("Looking for lines to connect."));
        look_for_lines_to_connect();
        //debug_current_and_destination(PSTR("Done with line connect."));
      }

      //debug_current_and_destination(PSTR("Done with current circle."));

    } while (location.x_index >= 0 && location.y_index >= 0);

    LEAVE:
    lcd_reset_alert_level();
    lcd_setstatuspgm(PSTR("Leaving G26"));

    retract_filament(destination);
    destination[Z_AXIS] = Z_CLEARANCE_BETWEEN_PROBES;

    //debug_current_and_destination(PSTR("ready to do Z-Raise."));
    move_to(destination[X_AXIS], destination[Y_AXIS], destination[Z_AXIS], 0); // Raise the nozzle
    //debug_current_and_destination(PSTR("done doing Z-Raise."));

    destination[X_AXIS] = x_pos;                                               // Move back to the starting position
    destination[Y_AXIS] = y_pos;
    //destination[Z_AXIS] = Z_CLEARANCE_BETWEEN_PROBES;                        // Keep the nozzle where it is

    move_to(destination[X_AXIS], destination[Y_AXIS], destination[Z_AXIS], 0); // Move back to the starting position
    //debug_current_and_destination(PSTR("done doing X/Y move."));

    ubl.has_control_of_lcd_panel = false;     // Give back control of the LCD Panel!

    if (!keep_heaters_on) {
      #if HAS_TEMP_BED
        thermalManager.setTargetBed(0);
      #endif
      thermalManager.setTargetHotend(0, 0);
    }
  }