diff --git a/Marlin/src/module/planner.cpp b/Marlin/src/module/planner.cpp index 605c2ecfbd..1c9601632d 100644 --- a/Marlin/src/module/planner.cpp +++ b/Marlin/src/module/planner.cpp @@ -793,21 +793,19 @@ void Planner::calculate_trapezoid_for_block(block_t * const block, const_float_t uint32_t cruise_rate = block->nominal_rate; #endif + const int32_t accel = block->acceleration_steps_per_s2; + // Steps for acceleration, plateau and deceleration int32_t plateau_steps = block->step_event_count; uint32_t accelerate_steps = 0, decelerate_steps = 0; - const int32_t accel = block->acceleration_steps_per_s2; - float inverse_accel = 0.0f; if (accel != 0) { - const float inverse_accel = 1.0f / accel, - half_inverse_accel = 0.5f * inverse_accel, - nominal_rate_sq = sq(float(block->nominal_rate)), - // Steps required for acceleration, deceleration to/from nominal rate - decelerate_steps_float = half_inverse_accel * (nominal_rate_sq - sq(float(final_rate))); - float accelerate_steps_float = half_inverse_accel * (nominal_rate_sq - sq(float(initial_rate))); + // Steps required for acceleration, deceleration to/from nominal rate + const float nominal_rate_sq = sq(float(block->nominal_rate)); + float accelerate_steps_float = (nominal_rate_sq - sq(float(initial_rate))) * (0.5f / accel); accelerate_steps = CEIL(accelerate_steps_float); + const float decelerate_steps_float = (nominal_rate_sq - sq(float(final_rate))) * (0.5f / accel); decelerate_steps = FLOOR(decelerate_steps_float); // Steps between acceleration and deceleration, if any @@ -830,10 +828,9 @@ void Planner::calculate_trapezoid_for_block(block_t * const block, const_float_t } #if ENABLED(S_CURVE_ACCELERATION) - const float rate_factor = inverse_accel * (STEPPER_TIMER_RATE); // Jerk controlled speed requires to express speed versus time, NOT steps - uint32_t acceleration_time = rate_factor * float(cruise_rate - initial_rate), - deceleration_time = rate_factor * float(cruise_rate - final_rate), + uint32_t acceleration_time = (float(cruise_rate - initial_rate) / accel) * (STEPPER_TIMER_RATE), + deceleration_time = (float(cruise_rate - final_rate) / accel) * (STEPPER_TIMER_RATE), // And to offload calculations from the ISR, we also calculate the inverse of those times here acceleration_time_inverse = get_period_inverse(acceleration_time), deceleration_time_inverse = get_period_inverse(deceleration_time);