mesh_index_pair unified_bed_leveling::find_closest_circle_to_print(const float &X, const float &Y) {
    float closest = 99999.99;
    mesh_index_pair return_val;

    return_val.x_index = return_val.y_index = -1;

    for (uint8_t i = 0; i < GRID_MAX_POINTS_X; i++) {
      for (uint8_t j = 0; j < GRID_MAX_POINTS_Y; j++) {
        if (!is_bit_set(circle_flags, i, j)) {
          const float mx = mesh_index_to_xpos(i),  // We found a circle that needs to be printed
                      my = mesh_index_to_ypos(j);

          // Get the distance to this intersection
          float f = HYPOT(X - mx, Y - my);

          // It is possible that we are being called with the values
          // to let us find the closest circle to the start position.
          // But if this is not the case, add a small weighting to the
          // distance calculation to help it choose a better place to continue.
          f += HYPOT(g26_x_pos - mx, g26_y_pos - my) / 15.0;

          // Add in the specified amount of Random Noise to our search
          if (random_deviation > 1.0)
            f += random(0.0, random_deviation);

          if (f < closest) {
            closest = f;              // We found a closer location that is still
            return_val.x_index = i;   // un-printed  --- save the data for it
            return_val.y_index = j;
            return_val.distance = closest;
          }
        }
      }
    }
    bit_set(circle_flags, return_val.x_index, return_val.y_index);   // Mark this location as done.
    return return_val;
  }
示例#2
0
    bool _O2 unified_bed_leveling::prepare_segmented_line_to(const float (&rtarget)[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 * (1.0f / (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 * (1.0f / (DELTA_SEGMENT_MIN_LENGTH))); // cartesian fixed segment length
      #endif

      NOLESS(segments, 1U);                        // must have at least one segment
      const float inv_segments = 1.0f / 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 = planner.get_axis_position_degrees(A_AXIS);
        scara_oldB = planner.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)) * (1.0f / (MESH_X_DIST)),
               cell_yi = (raw[Y_AXIS] - (MESH_MIN_Y)) * (1.0f / (MESH_Y_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) * (1.0f / (MESH_X_DIST)),   // z slope per x along y0 (lower left to lower right)
                    z_xmy1 = (z_x1y1 - z_x0y1) * (1.0f / (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 * (1.0f / (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) * (1.0f / (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

      return false; // caller will update current_position
    }
示例#3
0
    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
       */
      #if ENABLED(SKEW_CORRECTION)
        // For skew correction just adjust the destination point and we're done
        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] };
        planner.skew(start[X_AXIS], start[Y_AXIS], start[Z_AXIS]);
        planner.skew(end[X_AXIS], end[Y_AXIS], end[Z_AXIS]);
      #else
        const float (&start)[XYZE] = current_position,
                      (&end)[XYZE] = destination;
      #endif

      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_cartesian(xe=", destination[X_AXIS]);
        SERIAL_ECHOPAIR(", ye=", destination[Y_AXIS]);
        SERIAL_ECHOPAIR(", ze=", destination[Z_AXIS]);
        SERIAL_ECHOPAIR(", ee=", destination[E_AXIS]);
        SERIAL_CHAR(')');
        SERIAL_EOL();
        debug_current_and_destination(PSTR("Start of ubl.line_to_destination_cartesian()"));
      }

      // A move within the same cell needs no splitting
      if (cell_start_xi == cell_dest_xi && cell_start_yi == cell_dest_yi) {

        // For a move off the bed, use a constant Z raise
        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.  If the user has specified a UBL_Z_RAISE_WHEN_OFF_MESH
          // value, that will be used instead of a calculated (Bi-Linear interpolation) correction.

          const float z_raise = 0.0
            #ifdef UBL_Z_RAISE_WHEN_OFF_MESH
              + UBL_Z_RAISE_WHEN_OFF_MESH
            #endif
          ;
          planner.buffer_segment(end[X_AXIS], end[Y_AXIS], end[Z_AXIS] + z_raise, 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_cartesian()"));

          return;
        }

        FINAL_MOVE:

        // The distance is always MESH_X_DIST so multiply by the constant reciprocal.
        const float xratio = (end[X_AXIS] - mesh_index_to_xpos(cell_dest_xi)) * (1.0f / (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;

        // X cell-fraction done. Interpolate the two Z offsets with the Y fraction for the final Z offset.
        const float yratio = (end[Y_AXIS] - mesh_index_to_ypos(cell_dest_yi)) * (1.0f / (MESH_Y_DIST)),
                    z0 = cell_dest_yi < GRID_MAX_POINTS_Y - 1 ? (z1 + (z2 - z1) * yratio) * planner.fade_scaling_factor_for_z(end[Z_AXIS]) : 0.0;

        // Undefined parts of the Mesh in z_values[][] are NAN.
        // Replace NAN corrections with 0.0 to prevent NAN propagation.
        planner.buffer_segment(end[X_AXIS], end[Y_AXIS], end[Z_AXIS] + (isnan(z0) ? 0.0 : z0), end[E_AXIS], feed_rate, extruder);

        if (g26_debug_flag)
          debug_current_and_destination(PSTR("FINAL_MOVE in ubl.line_to_destination_cartesian()"));

        set_current_from_destination();
        return;
      }

      /**
       * Past this point the move is known to cross one or more mesh lines. Check for the most common
       * case - crossing only one X or Y line - after details are worked out to reduce computation.
       */

      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 extruder scaling factor for each partial move, checking for
       * zero-length moves that would result in an infinite scaling factor.
       * A float divide is required for this, but then it just multiplies.
       * Also select a scaling factor based on the larger of the X and Y
       * components. The larger of the two is used 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);

      /**
       * Handle vertical lines that stay within one column.
       * These need not be perfectly vertical.
       */
      if (dxi == 0) {             // Vertical line?
        current_yi += down_flag;  // Line going down? Just 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);

          /**
           * Skip the calculations for an infinite slope.
           * For others the next X is the same so this can 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]);

          // Undefined parts of the Mesh in z_values[][] are NAN.
          // Replace NAN corrections with 0.0 to prevent NAN propagation.
          if (isnan(z0)) z0 = 0.0;

          const float ry = mesh_index_to_ypos(current_yi);

          /**
           * Without this check, it's possible to generate a zero length move, as in the case where
           * the line is heading down, starting exactly on a mesh line boundary. Since this is rare
           * it might be fine to remove this check and let planner.buffer_segment() filter it out.
           */
          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_cartesian()"));

        // At the final destination? Usually not, but when on a Y Mesh Line it's completed.
        if (current_position[X_AXIS] != end[X_AXIS] || current_position[Y_AXIS] != end[Y_AXIS])
          goto FINAL_MOVE;

        set_current_from_destination();
        return;
      }

      /**
       * Handle horizontal lines that stay within one row.
       * These need not be perfectly horizontal.
       */
      if (dyi == 0) {             // Horizontal line?
        current_xi += left_flag;  // Heading left? Just go to the left edge of the 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]);

          // Undefined parts of the Mesh in z_values[][] are NAN.
          // Replace NAN corrections with 0.0 to prevent NAN propagation.
          if (isnan(z0)) z0 = 0.0;

          const float rx = mesh_index_to_xpos(current_xi);

          /**
           * Without this check, it's possible to generate a zero length move, as in the case where
           * the line is heading left, starting exactly on a mesh line boundary. Since this is rare
           * it might be fine to remove this check and let planner.buffer_segment() filter it out.
           */
          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];
            }

            if (!planner.buffer_segment(rx, ry, z_position + z0, e_position, feed_rate, extruder))
              break;
          } //else printf("FIRST MOVE PRUNED  ");
        }

        if (g26_debug_flag)
          debug_current_and_destination(PSTR("horizontal move done in ubl.line_to_destination_cartesian()"));

        if (current_position[X_AXIS] != end[X_AXIS] || current_position[Y_AXIS] != end[Y_AXIS])
          goto FINAL_MOVE;

        set_current_from_destination();
        return;
      }

      /**
       *
       * Handle 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 || yi_cnt) {

        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]);

          // Undefined parts of the Mesh in z_values[][] are NAN.
          // Replace NAN corrections with 0.0 to prevent NAN propagation.
          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];
          }
          if (!planner.buffer_segment(rx, next_mesh_line_y, z_position + z0, e_position, feed_rate, extruder))
            break;
          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]);

          // Undefined parts of the Mesh in z_values[][] are NAN.
          // Replace NAN corrections with 0.0 to prevent NAN propagation.
          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];
          }

          if (!planner.buffer_segment(next_mesh_line_x, ry, z_position + z0, e_position, feed_rate, extruder))
            break;
          current_xi += dxi;
          xi_cnt--;
        }

        if (xi_cnt < 0 || yi_cnt < 0) break; // Too far! Exit the loop and go to FINAL_MOVE
      }

      if (g26_debug_flag)
        debug_current_and_destination(PSTR("generic move done in ubl.line_to_destination_cartesian()"));

      if (current_position[X_AXIS] != end[X_AXIS] || current_position[Y_AXIS] != end[Y_AXIS])
        goto FINAL_MOVE;

      set_current_from_destination();
    }
  bool unified_bed_leveling::look_for_lines_to_connect() {
    float sx, sy, ex, ey;

    for (uint8_t i = 0; i < GRID_MAX_POINTS_X; i++) {
      for (uint8_t j = 0; j < GRID_MAX_POINTS_Y; j++) {

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

        if (i < GRID_MAX_POINTS_X) { // We can't connect to anything to the right than GRID_MAX_POINTS_X.
                                     // This is already a half circle because we are at the edge of the bed.

          if (is_bit_set(circle_flags, i, j) && is_bit_set(circle_flags, i + 1, j)) { // check if we can do a line to the left
            if (!is_bit_set(horizontal_mesh_line_flags, i, j)) {

              //
              // We found two circles that need a horizontal line to connect them
              // Print it!
              //
              sx = mesh_index_to_xpos(  i  ) + (SIZE_OF_INTERSECTION_CIRCLES - (SIZE_OF_CROSSHAIRS)); // right edge
              ex = mesh_index_to_xpos(i + 1) - (SIZE_OF_INTERSECTION_CIRCLES - (SIZE_OF_CROSSHAIRS)); // left edge

              sx = constrain(sx, X_MIN_POS + 1, X_MAX_POS - 1);
              sy = ey = constrain(mesh_index_to_ypos(j), Y_MIN_POS + 1, Y_MAX_POS - 1);
              ex = constrain(ex, X_MIN_POS + 1, X_MAX_POS - 1);

              if (position_is_reachable_raw_xy(sx, sy) && position_is_reachable_raw_xy(ex, ey)) {

                if (g26_debug_flag) {
                  SERIAL_ECHOPAIR(" Connecting with horizontal line (sx=", sx);
                  SERIAL_ECHOPAIR(", sy=", sy);
                  SERIAL_ECHOPAIR(") -> (ex=", ex);
                  SERIAL_ECHOPAIR(", ey=", ey);
                  SERIAL_CHAR(')');
                  SERIAL_EOL();
                  //debug_current_and_destination(PSTR("Connecting horizontal line."));
                }

                print_line_from_here_to_there(LOGICAL_X_POSITION(sx), LOGICAL_Y_POSITION(sy), g26_layer_height, LOGICAL_X_POSITION(ex), LOGICAL_Y_POSITION(ey), g26_layer_height);
              }
              bit_set(horizontal_mesh_line_flags, i, j);   // Mark it as done so we don't do it again, even if we skipped it
            }
          }

          if (j < GRID_MAX_POINTS_Y) { // We can't connect to anything further back than GRID_MAX_POINTS_Y.
                                           // This is already a half circle because we are at the edge  of the bed.

            if (is_bit_set(circle_flags, i, j) && is_bit_set(circle_flags, i, j + 1)) { // check if we can do a line straight down
              if (!is_bit_set( vertical_mesh_line_flags, i, j)) {
                //
                // We found two circles that need a vertical line to connect them
                // Print it!
                //
                sy = mesh_index_to_ypos(  j  ) + (SIZE_OF_INTERSECTION_CIRCLES - (SIZE_OF_CROSSHAIRS)); // top edge
                ey = mesh_index_to_ypos(j + 1) - (SIZE_OF_INTERSECTION_CIRCLES - (SIZE_OF_CROSSHAIRS)); // bottom edge

                sx = ex = constrain(mesh_index_to_xpos(i), X_MIN_POS + 1, X_MAX_POS - 1);
                sy = constrain(sy, Y_MIN_POS + 1, Y_MAX_POS - 1);
                ey = constrain(ey, Y_MIN_POS + 1, Y_MAX_POS - 1);

                if (position_is_reachable_raw_xy(sx, sy) && position_is_reachable_raw_xy(ex, ey)) {

                  if (g26_debug_flag) {
                    SERIAL_ECHOPAIR(" Connecting with vertical line (sx=", sx);
                    SERIAL_ECHOPAIR(", sy=", sy);
                    SERIAL_ECHOPAIR(") -> (ex=", ex);
                    SERIAL_ECHOPAIR(", ey=", ey);
                    SERIAL_CHAR(')');
                    SERIAL_EOL();
                    debug_current_and_destination(PSTR("Connecting vertical line."));
                  }
                  print_line_from_here_to_there(LOGICAL_X_POSITION(sx), LOGICAL_Y_POSITION(sy), g26_layer_height, LOGICAL_X_POSITION(ex), LOGICAL_Y_POSITION(ey), g26_layer_height);
                }
                bit_set(vertical_mesh_line_flags, i, j);   // Mark it as done so we don't do it again, even if skipped
              }
            }
          }
        }
      }
    }
    return false;
  }
  /**
   * 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);
    }
  }
示例#6
0
    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
       */
      #if ENABLED(SKEW_CORRECTION)
        // For skew correction just adjust the destination point and we're done
        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] };
        planner.skew(start[X_AXIS], start[Y_AXIS], start[Z_AXIS]);
        planner.skew(end[X_AXIS], end[Y_AXIS], end[Z_AXIS]);
      #else
        const float (&start)[XYZE] = current_position,
                      (&end)[XYZE] = destination;
      #endif

      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_cartesian(xe=", destination[X_AXIS]);
        SERIAL_ECHOPAIR(", ye=", destination[Y_AXIS]);
        SERIAL_ECHOPAIR(", ze=", destination[Z_AXIS]);
        SERIAL_ECHOPAIR(", ee=", destination[E_AXIS]);
        SERIAL_CHAR(')');
        SERIAL_EOL();
        debug_current_and_destination(PSTR("Start of ubl.line_to_destination_cartesian()"));
      }

      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_cartesian()"));

          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_cartesian()"));

        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_cartesian()"));

        //
        // 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_cartesian()"));

        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_cartesian()"));

      if (current_position[X_AXIS] != end[X_AXIS] || current_position[Y_AXIS] != end[Y_AXIS])
        goto FINAL_MOVE;

      set_current_from_destination();
    }