/** * Marlin 3D Printer Firmware * Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin] * * Based on Sprinter and grbl. * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . * */ #include "MarlinConfig.h" #if ENABLED(AUTO_BED_LEVELING_UBL) #include "Marlin.h" #include "ubl.h" #include "planner.h" #include "stepper.h" #include #include #if AVR_AT90USB1286_FAMILY // Teensyduino & Printrboard IDE extensions have compile errors without this inline void set_current_from_destination() { COPY(current_position, destination); } #else extern void set_current_from_destination(); #endif #if !UBL_SEGMENTED void unified_bed_leveling::line_to_destination_cartesian(const float &feed_rate, const uint8_t extruder) { /** * Much of the nozzle movement will be within the same cell. So we will do as little computation * as possible to determine if this is the case. If this move is within the same cell, we will * just do the required Z-Height correction, call the Planner's buffer_line() routine, and leave */ const float start[XYZE] = { current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS] }, end[XYZE] = { destination[X_AXIS], destination[Y_AXIS], destination[Z_AXIS], destination[E_AXIS] }; const int cell_start_xi = get_cell_index_x(start[X_AXIS]), cell_start_yi = get_cell_index_y(start[Y_AXIS]), cell_dest_xi = get_cell_index_x(end[X_AXIS]), cell_dest_yi = get_cell_index_y(end[Y_AXIS]); if (g26_debug_flag) { SERIAL_ECHOPAIR(" ubl.line_to_destination(xe=", end[X_AXIS]); SERIAL_ECHOPAIR(", ye=", end[Y_AXIS]); SERIAL_ECHOPAIR(", ze=", end[Z_AXIS]); SERIAL_ECHOPAIR(", ee=", end[E_AXIS]); SERIAL_CHAR(')'); SERIAL_EOL(); debug_current_and_destination(PSTR("Start of ubl.line_to_destination()")); } if (cell_start_xi == cell_dest_xi && cell_start_yi == cell_dest_yi) { // if the whole move is within the same cell, /** * we don't need to break up the move * * If we are moving off the print bed, we are going to allow the move at this level. * But we detect it and isolate it. For now, we just pass along the request. */ if (!WITHIN(cell_dest_xi, 0, GRID_MAX_POINTS_X - 1) || !WITHIN(cell_dest_yi, 0, GRID_MAX_POINTS_Y - 1)) { // Note: There is no Z Correction in this case. We are off the grid and don't know what // a reasonable correction would be. planner.buffer_segment(end[X_AXIS], end[Y_AXIS], end[Z_AXIS], end[E_AXIS], feed_rate, extruder); set_current_from_destination(); if (g26_debug_flag) debug_current_and_destination(PSTR("out of bounds in ubl.line_to_destination()")); return; } FINAL_MOVE: /** * Optimize some floating point operations here. We could call float get_z_correction(float x0, float y0) to * generate the correction for us. But we can lighten the load on the CPU by doing a modified version of the function. * We are going to only calculate the amount we are from the first mesh line towards the second mesh line once. * We will use this fraction in both of the original two Z Height calculations for the bi-linear interpolation. And, * instead of doing a generic divide of the distance, we know the distance is MESH_X_DIST so we can use the preprocessor * to create a 1-over number for us. That will allow us to do a floating point multiply instead of a floating point divide. */ const float xratio = (end[X_AXIS] - mesh_index_to_xpos(cell_dest_xi)) * (1.0 / (MESH_X_DIST)); float z1 = z_values[cell_dest_xi ][cell_dest_yi ] + xratio * (z_values[cell_dest_xi + 1][cell_dest_yi ] - z_values[cell_dest_xi][cell_dest_yi ]), z2 = z_values[cell_dest_xi ][cell_dest_yi + 1] + xratio * (z_values[cell_dest_xi + 1][cell_dest_yi + 1] - z_values[cell_dest_xi][cell_dest_yi + 1]); if (cell_dest_xi >= GRID_MAX_POINTS_X - 1) z1 = z2 = 0.0; // we are done with the fractional X distance into the cell. Now with the two Z-Heights we have calculated, we // are going to apply the Y-Distance into the cell to interpolate the final Z correction. const float yratio = (end[Y_AXIS] - mesh_index_to_ypos(cell_dest_yi)) * (1.0 / (MESH_Y_DIST)); float z0 = cell_dest_yi < GRID_MAX_POINTS_Y - 1 ? (z1 + (z2 - z1) * yratio) * planner.fade_scaling_factor_for_z(end[Z_AXIS]) : 0.0; /** * If part of the Mesh is undefined, it will show up as NAN * in z_values[][] and propagate through the * calculations. If our correction is NAN, we throw it out * because part of the Mesh is undefined and we don't have the * information we need to complete the height correction. */ if (isnan(z0)) z0 = 0.0; planner.buffer_segment(end[X_AXIS], end[Y_AXIS], end[Z_AXIS] + z0, end[E_AXIS], feed_rate, extruder); if (g26_debug_flag) debug_current_and_destination(PSTR("FINAL_MOVE in ubl.line_to_destination()")); set_current_from_destination(); return; } /** * If we get here, we are processing a move that crosses at least one Mesh Line. We will check * for the simple case of just crossing X or just crossing Y Mesh Lines after we get all the details * of the move figured out. We can process the easy case of just crossing an X or Y Mesh Line with less * computation and in fact most lines are of this nature. We will check for that in the following * blocks of code: */ const float dx = end[X_AXIS] - start[X_AXIS], dy = end[Y_AXIS] - start[Y_AXIS]; const int left_flag = dx < 0.0 ? 1 : 0, down_flag = dy < 0.0 ? 1 : 0; const float adx = left_flag ? -dx : dx, ady = down_flag ? -dy : dy; const int dxi = cell_start_xi == cell_dest_xi ? 0 : left_flag ? -1 : 1, dyi = cell_start_yi == cell_dest_yi ? 0 : down_flag ? -1 : 1; /** * Compute the scaling factor for the extruder for each partial move. * We need to watch out for zero length moves because it will cause us to * have an infinate scaling factor. We are stuck doing a floating point * divide to get our scaling factor, but after that, we just multiply by this * number. We also pick our scaling factor based on whether the X or Y * component is larger. We use the biggest of the two to preserve precision. */ const bool use_x_dist = adx > ady; float on_axis_distance = use_x_dist ? dx : dy, e_position = end[E_AXIS] - start[E_AXIS], z_position = end[Z_AXIS] - start[Z_AXIS]; const float e_normalized_dist = e_position / on_axis_distance, z_normalized_dist = z_position / on_axis_distance; int current_xi = cell_start_xi, current_yi = cell_start_yi; const float m = dy / dx, c = start[Y_AXIS] - m * start[X_AXIS]; const bool inf_normalized_flag = (isinf(e_normalized_dist) != 0), inf_m_flag = (isinf(m) != 0); /** * This block handles vertical lines. These are lines that stay within the same * X Cell column. They do not need to be perfectly vertical. They just can * not cross into another X Cell column. */ if (dxi == 0) { // Check for a vertical line current_yi += down_flag; // Line is heading down, we just want to go to the bottom while (current_yi != cell_dest_yi + down_flag) { current_yi += dyi; const float next_mesh_line_y = mesh_index_to_ypos(current_yi); /** * if the slope of the line is infinite, we won't do the calculations * else, we know the next X is the same so we can recover and continue! * Calculate X at the next Y mesh line */ const float rx = inf_m_flag ? start[X_AXIS] : (next_mesh_line_y - c) / m; float z0 = z_correction_for_x_on_horizontal_mesh_line(rx, current_xi, current_yi) * planner.fade_scaling_factor_for_z(end[Z_AXIS]); /** * If part of the Mesh is undefined, it will show up as NAN * in z_values[][] and propagate through the * calculations. If our correction is NAN, we throw it out * because part of the Mesh is undefined and we don't have the * information we need to complete the height correction. */ if (isnan(z0)) z0 = 0.0; const float ry = mesh_index_to_ypos(current_yi); /** * Without this check, it is possible for the algorithm to generate a zero length move in the case * where the line is heading down and it is starting right on a Mesh Line boundary. For how often that * happens, it might be best to remove the check and always 'schedule' the move because * the planner.buffer_segment() routine will filter it if that happens. */ if (ry != start[Y_AXIS]) { if (!inf_normalized_flag) { on_axis_distance = use_x_dist ? rx - start[X_AXIS] : ry - start[Y_AXIS]; e_position = start[E_AXIS] + on_axis_distance * e_normalized_dist; z_position = start[Z_AXIS] + on_axis_distance * z_normalized_dist; } else { e_position = end[E_AXIS]; z_position = end[Z_AXIS]; } planner.buffer_segment(rx, ry, z_position + z0, e_position, feed_rate, extruder); } //else printf("FIRST MOVE PRUNED "); } if (g26_debug_flag) debug_current_and_destination(PSTR("vertical move done in ubl.line_to_destination()")); // // Check if we are at the final destination. Usually, we won't be, but if it is on a Y Mesh Line, we are done. // if (current_position[X_AXIS] != end[X_AXIS] || current_position[Y_AXIS] != end[Y_AXIS]) goto FINAL_MOVE; set_current_from_destination(); return; } /** * * This block handles horizontal lines. These are lines that stay within the same * Y Cell row. They do not need to be perfectly horizontal. They just can * not cross into another Y Cell row. * */ if (dyi == 0) { // Check for a horizontal line current_xi += left_flag; // Line is heading left, we just want to go to the left // edge of this cell for the first move. while (current_xi != cell_dest_xi + left_flag) { current_xi += dxi; const float next_mesh_line_x = mesh_index_to_xpos(current_xi), ry = m * next_mesh_line_x + c; // Calculate Y at the next X mesh line float z0 = z_correction_for_y_on_vertical_mesh_line(ry, current_xi, current_yi) * planner.fade_scaling_factor_for_z(end[Z_AXIS]); /** * If part of the Mesh is undefined, it will show up as NAN * in z_values[][] and propagate through the * calculations. If our correction is NAN, we throw it out * because part of the Mesh is undefined and we don't have the * information we need to complete the height correction. */ if (isnan(z0)) z0 = 0.0; const float rx = mesh_index_to_xpos(current_xi); /** * Without this check, it is possible for the algorithm to generate a zero length move in the case * where the line is heading left and it is starting right on a Mesh Line boundary. For how often * that happens, it might be best to remove the check and always 'schedule' the move because * the planner.buffer_segment() routine will filter it if that happens. */ if (rx != start[X_AXIS]) { if (!inf_normalized_flag) { on_axis_distance = use_x_dist ? rx - start[X_AXIS] : ry - start[Y_AXIS]; e_position = start[E_AXIS] + on_axis_distance * e_normalized_dist; // is based on X or Y because this is a horizontal move z_position = start[Z_AXIS] + on_axis_distance * z_normalized_dist; } else { e_position = end[E_AXIS]; z_position = end[Z_AXIS]; } planner.buffer_segment(rx, ry, z_position + z0, e_position, feed_rate, extruder); } //else printf("FIRST MOVE PRUNED "); } if (g26_debug_flag) debug_current_and_destination(PSTR("horizontal move done in ubl.line_to_destination()")); if (current_position[X_AXIS] != end[X_AXIS] || current_position[Y_AXIS] != end[Y_AXIS]) goto FINAL_MOVE; set_current_from_destination(); return; } /** * * This block handles the generic case of a line crossing both X and Y Mesh lines. * */ int xi_cnt = cell_start_xi - cell_dest_xi, yi_cnt = cell_start_yi - cell_dest_yi; if (xi_cnt < 0) xi_cnt = -xi_cnt; if (yi_cnt < 0) yi_cnt = -yi_cnt; current_xi += left_flag; current_yi += down_flag; while (xi_cnt > 0 || yi_cnt > 0) { const float next_mesh_line_x = mesh_index_to_xpos(current_xi + dxi), next_mesh_line_y = mesh_index_to_ypos(current_yi + dyi), ry = m * next_mesh_line_x + c, // Calculate Y at the next X mesh line rx = (next_mesh_line_y - c) / m; // Calculate X at the next Y mesh line // (No need to worry about m being zero. // If that was the case, it was already detected // as a vertical line move above.) if (left_flag == (rx > next_mesh_line_x)) { // Check if we hit the Y line first // Yes! Crossing a Y Mesh Line next float z0 = z_correction_for_x_on_horizontal_mesh_line(rx, current_xi - left_flag, current_yi + dyi) * planner.fade_scaling_factor_for_z(end[Z_AXIS]); /** * If part of the Mesh is undefined, it will show up as NAN * in z_values[][] and propagate through the * calculations. If our correction is NAN, we throw it out * because part of the Mesh is undefined and we don't have the * information we need to complete the height correction. */ if (isnan(z0)) z0 = 0.0; if (!inf_normalized_flag) { on_axis_distance = use_x_dist ? rx - start[X_AXIS] : next_mesh_line_y - start[Y_AXIS]; e_position = start[E_AXIS] + on_axis_distance * e_normalized_dist; z_position = start[Z_AXIS] + on_axis_distance * z_normalized_dist; } else { e_position = end[E_AXIS]; z_position = end[Z_AXIS]; } planner.buffer_segment(rx, next_mesh_line_y, z_position + z0, e_position, feed_rate, extruder); current_yi += dyi; yi_cnt--; } else { // Yes! Crossing a X Mesh Line next float z0 = z_correction_for_y_on_vertical_mesh_line(ry, current_xi + dxi, current_yi - down_flag) * planner.fade_scaling_factor_for_z(end[Z_AXIS]); /** * If part of the Mesh is undefined, it will show up as NAN * in z_values[][] and propagate through the * calculations. If our correction is NAN, we throw it out * because part of the Mesh is undefined and we don't have the * information we need to complete the height correction. */ if (isnan(z0)) z0 = 0.0; if (!inf_normalized_flag) { on_axis_distance = use_x_dist ? next_mesh_line_x - start[X_AXIS] : ry - start[Y_AXIS]; e_position = start[E_AXIS] + on_axis_distance * e_normalized_dist; z_position = start[Z_AXIS] + on_axis_distance * z_normalized_dist; } else { e_position = end[E_AXIS]; z_position = end[Z_AXIS]; } planner.buffer_segment(next_mesh_line_x, ry, z_position + z0, e_position, feed_rate, extruder); current_xi += dxi; xi_cnt--; } if (xi_cnt < 0 || yi_cnt < 0) break; // we've gone too far, so exit the loop and move on to FINAL_MOVE } if (g26_debug_flag) debug_current_and_destination(PSTR("generic move done in ubl.line_to_destination()")); if (current_position[X_AXIS] != end[X_AXIS] || current_position[Y_AXIS] != end[Y_AXIS]) goto FINAL_MOVE; set_current_from_destination(); } #else // UBL_SEGMENTED #if IS_SCARA // scale the feed rate from mm/s to degrees/s static float scara_feed_factor, scara_oldA, scara_oldB; #endif // We don't want additional apply_leveling() performed by regular buffer_line or buffer_line_kinematic, // so we call buffer_segment directly here. Per-segmented leveling and kinematics performed first. inline void _O2 ubl_buffer_segment_raw(const float (&raw)[XYZE], const float &fr) { #if ENABLED(DELTA) // apply delta inverse_kinematics DELTA_RAW_IK(); planner.buffer_segment(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], raw[E_AXIS], fr, active_extruder); #elif IS_SCARA // apply scara inverse_kinematics (should be changed to save raw->logical->raw) inverse_kinematics(raw); // this writes delta[ABC] from raw[XYZE] // should move the feedrate scaling to scara inverse_kinematics const float adiff = FABS(delta[A_AXIS] - scara_oldA), bdiff = FABS(delta[B_AXIS] - scara_oldB); scara_oldA = delta[A_AXIS]; scara_oldB = delta[B_AXIS]; float s_feedrate = max(adiff, bdiff) * scara_feed_factor; planner.buffer_segment(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], raw[E_AXIS], s_feedrate, active_extruder); #else // CARTESIAN planner.buffer_segment(raw[X_AXIS], raw[Y_AXIS], raw[Z_AXIS], raw[E_AXIS], fr, active_extruder); #endif } #if IS_SCARA #define DELTA_SEGMENT_MIN_LENGTH 0.25 // SCARA minimum segment size is 0.25mm #elif ENABLED(DELTA) #define DELTA_SEGMENT_MIN_LENGTH 0.10 // mm (still subject to DELTA_SEGMENTS_PER_SECOND) #else // CARTESIAN #ifdef LEVELED_SEGMENT_LENGTH #define DELTA_SEGMENT_MIN_LENGTH LEVELED_SEGMENT_LENGTH #else #define DELTA_SEGMENT_MIN_LENGTH 1.00 // mm (similar to G2/G3 arc segmentation) #endif #endif /** * Prepare a segmented linear move for DELTA/SCARA/CARTESIAN with UBL and FADE semantics. * This calls planner.buffer_segment multiple times for small incremental moves. * Returns true if did NOT move, false if moved (requires current_position update). */ bool _O2 unified_bed_leveling::prepare_segmented_line_to(const float (&in_target)[XYZE], const float &feedrate) { if (!position_is_reachable(rtarget[X_AXIS], rtarget[Y_AXIS])) // fail if moving outside reachable boundary return true; // did not move, so current_position still accurate const float total[XYZE] = { rtarget[X_AXIS] - current_position[X_AXIS], rtarget[Y_AXIS] - current_position[Y_AXIS], rtarget[Z_AXIS] - current_position[Z_AXIS], rtarget[E_AXIS] - current_position[E_AXIS] }; const float cartesian_xy_mm = HYPOT(total[X_AXIS], total[Y_AXIS]); // total horizontal xy distance #if IS_KINEMATIC const float seconds = cartesian_xy_mm / feedrate; // seconds to move xy distance at requested rate uint16_t segments = lroundf(delta_segments_per_second * seconds), // preferred number of segments for distance @ feedrate seglimit = lroundf(cartesian_xy_mm * (1.0 / (DELTA_SEGMENT_MIN_LENGTH))); // number of segments at minimum segment length NOMORE(segments, seglimit); // limit to minimum segment length (fewer segments) #else uint16_t segments = lroundf(cartesian_xy_mm * (1.0 / (DELTA_SEGMENT_MIN_LENGTH))); // cartesian fixed segment length #endif NOLESS(segments, 1); // must have at least one segment const float inv_segments = 1.0 / segments; // divide once, multiply thereafter #if IS_SCARA // scale the feed rate from mm/s to degrees/s scara_feed_factor = cartesian_xy_mm * inv_segments * feedrate; scara_oldA = stepper.get_axis_position_degrees(A_AXIS); scara_oldB = stepper.get_axis_position_degrees(B_AXIS); #endif const float diff[XYZE] = { total[X_AXIS] * inv_segments, total[Y_AXIS] * inv_segments, total[Z_AXIS] * inv_segments, total[E_AXIS] * inv_segments }; // Note that E segment distance could vary slightly as z mesh height // changes for each segment, but small enough to ignore. float raw[XYZE] = { current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS] }; // Only compute leveling per segment if ubl active and target below z_fade_height. if (!planner.leveling_active || !planner.leveling_active_at_z(rtarget[Z_AXIS])) { // no mesh leveling while (--segments) { LOOP_XYZE(i) raw[i] += diff[i]; ubl_buffer_segment_raw(raw, feedrate); } ubl_buffer_segment_raw(rtarget, feedrate); return false; // moved but did not set_current_from_destination(); } // Otherwise perform per-segment leveling #if ENABLED(ENABLE_LEVELING_FADE_HEIGHT) const float fade_scaling_factor = planner.fade_scaling_factor_for_z(rtarget[Z_AXIS]); #endif // increment to first segment destination LOOP_XYZE(i) raw[i] += diff[i]; for(;;) { // for each mesh cell encountered during the move // Compute mesh cell invariants that remain constant for all segments within cell. // Note for cell index, if point is outside the mesh grid (in MESH_INSET perimeter) // the bilinear interpolation from the adjacent cell within the mesh will still work. // Inner loop will exit each time (because out of cell bounds) but will come back // in top of loop and again re-find same adjacent cell and use it, just less efficient // for mesh inset area. int8_t cell_xi = (raw[X_AXIS] - (MESH_MIN_X)) * (1.0 / (MESH_X_DIST)), cell_yi = (raw[Y_AXIS] - (MESH_MIN_Y)) * (1.0 / (MESH_X_DIST)); cell_xi = constrain(cell_xi, 0, (GRID_MAX_POINTS_X) - 1); cell_yi = constrain(cell_yi, 0, (GRID_MAX_POINTS_Y) - 1); const float x0 = mesh_index_to_xpos(cell_xi), // 64 byte table lookup avoids mul+add y0 = mesh_index_to_ypos(cell_yi); float z_x0y0 = z_values[cell_xi ][cell_yi ], // z at lower left corner z_x1y0 = z_values[cell_xi+1][cell_yi ], // z at upper left corner z_x0y1 = z_values[cell_xi ][cell_yi+1], // z at lower right corner z_x1y1 = z_values[cell_xi+1][cell_yi+1]; // z at upper right corner if (isnan(z_x0y0)) z_x0y0 = 0; // ideally activating planner.leveling_active (G29 A) if (isnan(z_x1y0)) z_x1y0 = 0; // should refuse if any invalid mesh points if (isnan(z_x0y1)) z_x0y1 = 0; // in order to avoid isnan tests per cell, if (isnan(z_x1y1)) z_x1y1 = 0; // thus guessing zero for undefined points float cx = raw[X_AXIS] - x0, // cell-relative x and y cy = raw[Y_AXIS] - y0; const float z_xmy0 = (z_x1y0 - z_x0y0) * (1.0 / (MESH_X_DIST)), // z slope per x along y0 (lower left to lower right) z_xmy1 = (z_x1y1 - z_x0y1) * (1.0 / (MESH_X_DIST)); // z slope per x along y1 (upper left to upper right) float z_cxy0 = z_x0y0 + z_xmy0 * cx; // z height along y0 at cx (changes for each cx in cell) const float z_cxy1 = z_x0y1 + z_xmy1 * cx, // z height along y1 at cx z_cxyd = z_cxy1 - z_cxy0; // z height difference along cx from y0 to y1 float z_cxym = z_cxyd * (1.0 / (MESH_Y_DIST)); // z slope per y along cx from y0 to y1 (changes for each cx in cell) // float z_cxcy = z_cxy0 + z_cxym * cy; // interpolated mesh z height along cx at cy (do inside the segment loop) // As subsequent segments step through this cell, the z_cxy0 intercept will change // and the z_cxym slope will change, both as a function of cx within the cell, and // each change by a constant for fixed segment lengths. const float z_sxy0 = z_xmy0 * diff[X_AXIS], // per-segment adjustment to z_cxy0 z_sxym = (z_xmy1 - z_xmy0) * (1.0 / (MESH_Y_DIST)) * diff[X_AXIS]; // per-segment adjustment to z_cxym for(;;) { // for all segments within this mesh cell if (--segments == 0) // if this is last segment, use rtarget for exact COPY(raw, rtarget); const float z_cxcy = (z_cxy0 + z_cxym * cy) // interpolated mesh z height along cx at cy #if ENABLED(ENABLE_LEVELING_FADE_HEIGHT) * fade_scaling_factor // apply fade factor to interpolated mesh height #endif ; const float z = raw[Z_AXIS]; raw[Z_AXIS] += z_cxcy; ubl_buffer_segment_raw(raw, feedrate); raw[Z_AXIS] = z; if (segments == 0) // done with last segment return false; // did not set_current_from_destination() LOOP_XYZE(i) raw[i] += diff[i]; cx += diff[X_AXIS]; cy += diff[Y_AXIS]; if (!WITHIN(cx, 0, MESH_X_DIST) || !WITHIN(cy, 0, MESH_Y_DIST)) // done within this cell, break to next break; // Next segment still within same mesh cell, adjust the per-segment // slope and intercept to compute next z height. z_cxy0 += z_sxy0; // adjust z_cxy0 by per-segment z_sxy0 z_cxym += z_sxym; // adjust z_cxym by per-segment z_sxym } // segment loop } // cell loop } #endif // UBL_SEGMENTED #endif // AUTO_BED_LEVELING_UBL