From 22489c69cbb5fc939789b93b0fa12367cf2b14cc Mon Sep 17 00:00:00 2001
From: Nico Tonnhofer <wurstnase.reprap@gmail.com>
Date: Tue, 3 Jan 2017 21:10:29 +0100
Subject: [PATCH] dda.c: simply resort the values and save up to 8 clocks

ATmega sizes               '168   '328(P)   '644(P)     '1280
Program:  18266 bytes      128%       60%       29%       15%
   Data:   1936 bytes      190%       95%       48%       24%
 EEPROM:     32 bytes        4%        2%        2%        1%

short-moves.gcode statistics:
LED on occurences: 888.
LED on time minimum: 243 clock cycles.
LED on time maximum: 555 clock cycles.
LED on time average: 250.375 clock cycles.

smooth-curves.gcode statistics:
LED on occurences: 22589.
LED on time minimum: 243 clock cycles.
LED on time maximum: 572 clock cycles.
LED on time average: 292.139 clock cycles.

triangle-odd.gcode statistics:
LED on occurences: 1636.
LED on time minimum: 243 clock cycles.
LED on time maximum: 555 clock cycles.
LED on time average: 275.699 clock cycles.
---
 dda.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/dda.c b/dda.c
index b1245b8..b7e8efb 100644
--- a/dda.c
+++ b/dda.c
@@ -538,33 +538,33 @@ void dda_step(DDA *dda) {
     if (move_state.steps[X]) {
       move_state.counter[X] -= dda->delta[X];
       if (move_state.counter[X] < 0) {
+        move_state.counter[X] += dda->total_steps;
         x_step();
         move_state.steps[X]--;
-        move_state.counter[X] += dda->total_steps;
       }
 		}
     if (move_state.steps[Y]) {
       move_state.counter[Y] -= dda->delta[Y];
       if (move_state.counter[Y] < 0) {
+        move_state.counter[Y] += dda->total_steps;
         y_step();
         move_state.steps[Y]--;
-        move_state.counter[Y] += dda->total_steps;
       }
 		}
     if (move_state.steps[Z]) {
       move_state.counter[Z] -= dda->delta[Z];
       if (move_state.counter[Z] < 0) {
+        move_state.counter[Z] += dda->total_steps;
         z_step();
         move_state.steps[Z]--;
-        move_state.counter[Z] += dda->total_steps;
       }
 		}
     if (move_state.steps[E]) {
       move_state.counter[E] -= dda->delta[E];
       if (move_state.counter[E] < 0) {
+        move_state.counter[E] += dda->total_steps;
         e_step();
         move_state.steps[E]--;
-        move_state.counter[E] += dda->total_steps;
       }
 		}
     move_state.step_no++;