🔧 Allow FTM + Nonlinear Extrusion (#28250)

Co-authored-by: Scott Lahteine <thinkyhead@users.noreply.github.com>

Marlin/src/inc/SanityCheck.h

@@ -870,8 +870,8 @@ static_assert(COUNT(arm) == LOGICAL_AXES, "AXIS_RELATIVE_MODES must contain " _L
 #if ENABLED(NONLINEAR_EXTRUSION)
   #if HAS_MULTI_EXTRUDER
     #error "NONLINEAR_EXTRUSION doesn't currently support multi-extruder setups."
-  #elif DISABLED(CPU_32_BIT)
-    #error "NONLINEAR_EXTRUSION requires a 32-bit CPU."
+  #elif NONE(CPU_32_BIT, NO_STANDARD_MOTION)
+    #error "NONLINEAR_EXTRUSION requires a 32-bit CPU or NO_STANDARD_MOTION."
   #endif
 #endif
 
@@ -4515,9 +4515,7 @@ static_assert(_PLUS_TEST(3), "DEFAULT_MAX_ACCELERATION values must be positive."
     #error "EMERGENCY_PARSER is required with FTM_RESONANCE_TEST (to cancel the test)."
   #endif
   #if !HAS_STANDARD_MOTION
-    #if ENABLED(NONLINEAR_EXTRUSION)
-      #error "NONLINEAR_EXTRUSION is not yet available in FT_MOTION. Disable NO_STANDARD_MOTION if you require it."
-    #elif ENABLED(SMOOTH_LIN_ADVANCE)
+    #if ENABLED(SMOOTH_LIN_ADVANCE)
       #error "SMOOTH_LIN_ADVANCE is not yet available in FT_MOTION. Disable NO_STANDARD_MOTION if you require it."
     #elif ENABLED(MIXING_EXTRUDER)
       #error "MIXING_EXTRUDER is not yet available in FT_MOTION. Disable NO_STANDARD_MOTION if you require it."

Marlin/src/inc/Warnings.cpp

@@ -941,9 +941,6 @@
   #if ENABLED(I2S_STEPPER_STREAM)
     #warning "FT_MOTION has not been tested with I2S_STEPPER_STREAM."
   #endif
-  #if ENABLED(NONLINEAR_EXTRUSION)
-    #warning "NONLINEAR_EXTRUSION does not (currently) operate when FT_MOTION is the active motion system."
-  #endif
   #if ENABLED(LIN_ADVANCE)
     #warning "Be aware that FT_MOTION K factor is now set with M900 K (same as LIN_ADVANCE)."
     #if DISABLED(FTM_SMOOTHING)

Marlin/src/module/ft_motion.cpp

@@ -478,21 +478,42 @@ xyze_float_t FTMotion::calc_traj_point(const float dist) {
   LOGICAL_AXIS_MAP_LC(_SET_TRAJ);
 
   #if FTM_HAS_LIN_ADVANCE
-    const float advK = planner.get_advance_k();
-    if (advK) {
-      const float traj_e = traj_coords.e;
-      if (use_advance_lead) {
-        // Don't apply LA to retract/unretract blocks
-        const float e_rate = (traj_e - prev_traj_e) * (FTM_FS);
+
+    // Apply LA/NLE only to printing (not retract/unretract) blocks
+
+    if (use_advance_lead) {
+      const float advK = planner.get_advance_k();
+      if (advK || TERN0(NONLINEAR_EXTRUSION, stepper.ne.settings.enabled)) {
+        float traj_e = traj_coords.e;
+        const float traj_e_delta = traj_e - prev_traj_e; // extruder delta in mm, always positive for use_advance_lead (printing moves)
+        const float e_rate = traj_e_delta * FTM_FS;      // extruder velocity in mm/s
+
         traj_coords.e += e_rate * advK;
+
+        #if ENABLED(NONLINEAR_EXTRUSION)
+          if (stepper.ne.settings.enabled) {
+            const nonlinear_coeff_t &coeff = stepper.ne.settings.coeff;
+            const float multiplier = max(coeff.C, coeff.A * sq(e_rate) + coeff.B * e_rate + coeff.C),
+                        nle_term = traj_e_delta * (multiplier - 1);
+
+            traj_coords.e += nle_term;
+            traj_e += nle_term;
+            startPos.e += nle_term;
+            endPos_prevBlock.e += nle_term;
+          }
+        #endif
+
+        prev_traj_e = traj_e;
       }
-      prev_traj_e = traj_e;
     }
-  #endif
+
+  #endif // FTM_HAS_LIN_ADVANCE
 
   // Update shaping parameters if needed.
   switch (cfg.dynFreqMode) {
+
     #if HAS_DYNAMIC_FREQ_MM
+
       case dynFreqMode_Z_BASED: {
         static float oldz = 0.0f;
         const float z = traj_coords.z;
@@ -509,9 +530,11 @@ xyze_float_t FTMotion::calc_traj_point(const float dist) {
           shaping.refresh_largest_delay_samples();
         }
       } break;
+
     #endif
 
     #if HAS_DYNAMIC_FREQ_G
+
       case dynFreqMode_MASS_BASED:
         // Update constantly. The optimization done for Z value makes
         // less sense for E, as E is expected to constantly change.
@@ -523,6 +546,7 @@ xyze_float_t FTMotion::calc_traj_point(const float dist) {
         #endif
         shaping.refresh_largest_delay_samples();
         break;
+
     #endif
 
     default: break;

Marlin/src/module/stepper.h

@@ -292,12 +292,14 @@ constexpr ena_mask_t enable_overlap[] = {
     #define NONLINEAR_EXTRUSION_Q24 1
   #endif
 
+  typedef struct {
+    float A, B, C;
+    void reset() { A = B = 0.0f; C = 1.0f; }
+  } nonlinear_coeff_t;
+
   typedef struct {
     bool enabled;
-    struct {
-      float A, B, C;
-      void reset() { A = B = 0.0f; C = 1.0f; }
-    } coeff;
+    nonlinear_coeff_t coeff;
     void reset() {
       enabled = ENABLED(NONLINEAR_EXTRUSION_DEFAULT_ON);
       coeff.reset();