stepcompress: Pass delta velocity and acceleration directly to C code

Update the C delta kinematic code to take velocity and acceleration
directly in step distances and clock ticks.  This simplifies the
mcu.py python code as it only needs to do unit and axis conversion.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

1 files changed, 13 insertions, 22 deletions

diff --git a/klippy/mcu.py b/klippy/mcu.py
index 741ac0aa..26e98d39 100644
--- a/klippy/mcu.py
+++ b/klippy/mcu.py
@@ -130,36 +130,27 @@ class MCU_stepper:
         self._commanded_pos += count
     def step_delta_const(self, mcu_time, start_pos, dist, cruise_v
                          , height_base, closestxy_d, closest_height2, movez_r):
-        mcu_freq = self._mcu_freq
-        step_dist = self._step_dist
-        height = self._commanded_pos*step_dist - height_base
-        if dist < 0:
-            dist = -dist
-            step_dist = -step_dist
+        inv_step_dist = self._inv_step_dist
+        height = self._commanded_pos - height_base * inv_step_dist
         count = self._ffi_lib.stepcompress_push_delta_const(
-            self._stepqueue, mcu_time * mcu_freq, dist, -start_pos
-            , mcu_freq / cruise_v, step_dist
-            , height, closestxy_d, closest_height2, movez_r)
+            self._stepqueue, mcu_time * self._mcu_freq,
+            -start_pos * inv_step_dist, dist * inv_step_dist,
+            cruise_v * self._velocity_factor,
+            height, closestxy_d * inv_step_dist,
+            closest_height2 * inv_step_dist**2, movez_r)
         if count == STEPCOMPRESS_ERROR_RET:
             raise error("Internal error in stepcompress")
         self._commanded_pos += count
     def step_delta_accel(self, mcu_time, start_pos, dist, start_v, accel
                          , height_base, closestxy_d, closest_height2, movez_r):
         inv_step_dist = self._inv_step_dist
-        mcu_freq = self._mcu_freq
-        inv_accel = 1. / accel
-        time_offset = start_v * inv_accel * mcu_freq
-        accel_offset = start_v**2 * 0.5 * inv_accel
-        step_dist = self._step_dist
-        height = self._commanded_pos*step_dist - height_base
-        if dist < 0:
-            dist = -dist
-            step_dist = -step_dist
-        clock = mcu_time * mcu_freq - time_offset
+        height = self._commanded_pos - height_base * inv_step_dist
         count = self._ffi_lib.stepcompress_push_delta_accel(
-            self._stepqueue, clock, dist, accel_offset - start_pos
-            , 2. * inv_accel * mcu_freq**2, step_dist
-            , height, closestxy_d, closest_height2, movez_r)
+            self._stepqueue, mcu_time * self._mcu_freq,
+            -start_pos * inv_step_dist, dist * inv_step_dist,
+            start_v * self._velocity_factor, accel * self._accel_factor,
+            height, closestxy_d * inv_step_dist,
+            closest_height2 * inv_step_dist**2, movez_r)
         if count == STEPCOMPRESS_ERROR_RET:
             raise error("Internal error in stepcompress")
         self._commanded_pos += count