Add realtime delta geometry in Marlin_main.cpp.

Marlin/Marlin.h

 void ClearToSend();
 
 void get_coordinates();
+void calculate_delta(float cartesian[3]);
 void prepare_move();
 void kill();
 void Stop();

Marlin/Marlin_main.cpp

 //===========================================================================
 const char axis_codes[NUM_AXIS] = {'X', 'Y', 'Z', 'E'};
 static float destination[NUM_AXIS] = {  0.0, 0.0, 0.0, 0.0};
+static float delta[3] = {0.0, 0.0, 0.0};
 static float offset[3] = {0.0, 0.0, 0.0};
 static bool home_all_axis = true;
 static float feedrate = 1500.0, next_feedrate, saved_feedrate;
       feedrate = 0.0;
       home_all_axis = !((code_seen(axis_codes[0])) || (code_seen(axis_codes[1])) || (code_seen(axis_codes[2])));
       
-      #if Z_HOME_DIR > 0                      // If homing away from BED do Z first
-      if((home_all_axis) || (code_seen(axis_codes[Z_AXIS]))) {
-        HOMEAXIS(Z);
-      }
-      #endif
-      
       #ifdef QUICK_HOME
-      if((home_all_axis)||( code_seen(axis_codes[X_AXIS]) && code_seen(axis_codes[Y_AXIS])) )  //first diagonal move
+      if (home_all_axis)  // Move all carriages up together until the first endstop is hit.
       {
-        current_position[X_AXIS] = 0;current_position[Y_AXIS] = 0;  
-
+        current_position[X_AXIS] = 0;
+        current_position[Y_AXIS] = 0;
+        current_position[Z_AXIS] = 0;
         plan_set_position(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS]); 
-        destination[X_AXIS] = 1.5 * X_MAX_LENGTH * X_HOME_DIR;destination[Y_AXIS] = 1.5 * Y_MAX_LENGTH * Y_HOME_DIR;  
-        feedrate = homing_feedrate[X_AXIS]; 
-        if(homing_feedrate[Y_AXIS]<feedrate)
-          feedrate =homing_feedrate[Y_AXIS]; 
-        plan_buffer_line(destination[X_AXIS], destination[Y_AXIS], destination[Z_AXIS], destination[E_AXIS], feedrate/60, active_extruder);
-        st_synchronize();
-    
-        axis_is_at_home(X_AXIS);
-        axis_is_at_home(Y_AXIS);
-        plan_set_position(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS]);
-        destination[X_AXIS] = current_position[X_AXIS];
-        destination[Y_AXIS] = current_position[Y_AXIS];
+
+        destination[X_AXIS] = 1.5 * X_MAX_LENGTH * X_HOME_DIR;
+        destination[Y_AXIS] = 1.5 * Y_MAX_LENGTH * Y_HOME_DIR;
+        destination[Z_AXIS] = 1.5 * Z_MAX_LENGTH * Z_HOME_DIR;
+        feedrate = 1.732 * homing_feedrate[X_AXIS];
         plan_buffer_line(destination[X_AXIS], destination[Y_AXIS], destination[Z_AXIS], destination[E_AXIS], feedrate/60, active_extruder);
-        feedrate = 0.0;
         st_synchronize();
         endstops_hit_on_purpose();
+
+        current_position[X_AXIS] = destination[X_AXIS];
+        current_position[Y_AXIS] = destination[Y_AXIS];
+        current_position[Z_AXIS] = destination[Z_AXIS];
       }
       #endif
       
         HOMEAXIS(Y);
       }
       
-      #if Z_HOME_DIR < 0                      // If homing towards BED do Z last
       if((home_all_axis) || (code_seen(axis_codes[Z_AXIS]))) {
         HOMEAXIS(Z);
       }
-      #endif
       
       if(code_seen(axis_codes[X_AXIS])) 
       {
           current_position[Z_AXIS]=code_value()+add_homeing[2];
         }
       }
-      plan_set_position(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS]);
+      calculate_delta(current_position);
+      plan_set_position(delta[X_AXIS], delta[Y_AXIS], delta[Z_AXIS], current_position[E_AXIS]);
       
       #ifdef ENDSTOPS_ONLY_FOR_HOMING
         enable_endstops(false);
   }
 }
 
+void calculate_delta(float cartesian[3])
+{
+  delta[X_AXIS] = sqrt(sq(DELTA_DIAGONAL_ROD)
+                       - sq(DELTA_TOWER1_X-cartesian[X_AXIS])
+                       - sq(DELTA_TOWER1_Y-cartesian[Y_AXIS])
+                       ) + cartesian[Z_AXIS];
+  delta[Y_AXIS] = sqrt(sq(DELTA_DIAGONAL_ROD)
+                       - sq(DELTA_TOWER2_X-cartesian[X_AXIS])
+                       - sq(DELTA_TOWER2_Y-cartesian[Y_AXIS])
+                       ) + cartesian[Z_AXIS];
+  delta[Z_AXIS] = sqrt(sq(DELTA_DIAGONAL_ROD)
+                       - sq(DELTA_TOWER3_X-cartesian[X_AXIS])
+                       - sq(DELTA_TOWER3_Y-cartesian[Y_AXIS])
+                       ) + cartesian[Z_AXIS];
+  /*
+  SERIAL_ECHOPGM("cartesian x="); SERIAL_ECHO(cartesian[X_AXIS]);
+  SERIAL_ECHOPGM(" y="); SERIAL_ECHO(cartesian[Y_AXIS]);
+  SERIAL_ECHOPGM(" z="); SERIAL_ECHOLN(cartesian[Z_AXIS]);
+
+  SERIAL_ECHOPGM("delta x="); SERIAL_ECHO(delta[X_AXIS]);
+  SERIAL_ECHOPGM(" y="); SERIAL_ECHO(delta[Y_AXIS]);
+  SERIAL_ECHOPGM(" z="); SERIAL_ECHOLN(delta[Z_AXIS]);
+  */
+}
+
 void prepare_move()
 {
   clamp_to_software_endstops(destination);
 
   previous_millis_cmd = millis(); 
-  // Do not use feedmultiply for E or Z only moves
-  if( (current_position[X_AXIS] == destination [X_AXIS]) && (current_position[Y_AXIS] == destination [Y_AXIS])) {
-      plan_buffer_line(destination[X_AXIS], destination[Y_AXIS], destination[Z_AXIS], destination[E_AXIS], feedrate/60, active_extruder);
+
+  float difference[NUM_AXIS];
+  for (int8_t i=0; i < NUM_AXIS; i++) {
+    difference[i] = destination[i] - current_position[i];
   }
-  else {
-    plan_buffer_line(destination[X_AXIS], destination[Y_AXIS], destination[Z_AXIS], destination[E_AXIS], feedrate*feedmultiply/60/100.0, active_extruder);
+  float cartesian_mm = sqrt(sq(difference[X_AXIS]) +
+                            sq(difference[Y_AXIS]) +
+                            sq(difference[Z_AXIS]));
+  if (cartesian_mm < 0.000001) { cartesian_mm = abs(difference[E_AXIS]); }
+  if (cartesian_mm < 0.000001) { return; }
+  float seconds = 6000 * cartesian_mm / feedrate / feedmultiply;
+  int steps = max(1, int(DELTA_SEGMENTS_PER_SECOND * seconds));
+  // SERIAL_ECHOPGM("mm="); SERIAL_ECHO(cartesian_mm);
+  // SERIAL_ECHOPGM(" seconds="); SERIAL_ECHO(seconds);
+  // SERIAL_ECHOPGM(" steps="); SERIAL_ECHOLN(steps);
+  for (int s = 1; s <= steps; s++) {
+    float fraction = float(s) / float(steps);
+    for(int8_t i=0; i < NUM_AXIS; i++) {
+      destination[i] = current_position[i] + difference[i] * fraction;
+    }
+    calculate_delta(destination);
+    plan_buffer_line(delta[X_AXIS], delta[Y_AXIS], delta[Z_AXIS],
+                     destination[E_AXIS], feedrate*feedmultiply/60/100.0,
+                     active_extruder);
   }
+
   for(int8_t i=0; i < NUM_AXIS; i++) {
     current_position[i] = destination[i];
   }