diff --git a/Marlin/planner.cpp b/Marlin/planner.cpp index 17746d9210..b761c9a5ed 100644 --- a/Marlin/planner.cpp +++ b/Marlin/planner.cpp @@ -1293,22 +1293,28 @@ void Planner::_buffer_line(const float &a, const float &b, const float &c, const #if ENABLED(LIN_ADVANCE) - // Don't use LIN_ADVANCE for blocks if: - // !block->steps[E_AXIS]: We don't have E steps todo (Travel move) - // !block->steps[X_AXIS] && !block->steps[Y_AXIS]: We don't have a movement in XY direction (Retract / Prime moves) - // extruder_advance_k == 0.0: There is no advance factor set - // block->steps[E_AXIS] == block->step_event_count: A problem occurs when there's a very tiny move before a retract. - // In this case, the retract and the move will be executed together. - // This leads to an enormous number of advance steps due to a huge e_acceleration. - // The math is correct, but you don't want a retract move done with advance! - // de_float <= 0.0: Extruder is running in reverse direction (for example during "Wipe while retracting" (Slic3r) or "Combing" (Cura) movements) - if (!esteps || (!block->steps[X_AXIS] && !block->steps[Y_AXIS]) || extruder_advance_k == 0.0 || (uint32_t)esteps == block->step_event_count || de_float <= 0.0) { - block->use_advance_lead = false; - } - else { - block->use_advance_lead = true; + // + // Use LIN_ADVANCE for blocks if all these are true: + // + // esteps : We have E steps todo (a printing move) + // + // block->steps[X_AXIS] || block->steps[Y_AXIS] : We have a movement in XY direction (i.e., not retract / prime). + // + // extruder_advance_k : There is an advance factor set. + // + // block->steps[E_AXIS] != block->step_event_count : A problem occurs if the move before a retract is too small. + // In that case, the retract and move will be executed together. + // This leads to too many advance steps due to a huge e_acceleration. + // The math is good, but we must avoid retract moves with advance! + // de_float > 0.0 : Extruder is running forward (e.g., for "Wipe while retracting" (Slic3r) or "Combing" (Cura) moves) + // + block->use_advance_lead = esteps + && (block->steps[X_AXIS] || block->steps[Y_AXIS]) + && extruder_advance_k + && (uint32_t)esteps != block->step_event_count + && de_float > 0.0; + if (block->use_advance_lead) block->abs_adv_steps_multiplier8 = lround(extruder_advance_k * (de_float / mm_D_float) * block->nominal_speed / (float)block->nominal_rate * axis_steps_per_mm[E_AXIS_N] * 256.0); - } #elif ENABLED(ADVANCE)