fixed freezing up on non-tangent

Author: grandixximo

src/emc/motion_planning/motion_planning_9d.cc

@@ -2111,10 +2111,14 @@ int applyLimitingVelocities_9D(TC_QUEUE_STRUCT *queue,
 
         double v_new = smoothing.v_smooth[k];
 
-        if (tc->term_cond == TC_TERM_COND_TANGENT && tc->finalvel > 0.0) {
-            if (v_new < 1e-6) {
+        if (tc->term_cond == TC_TERM_COND_TANGENT) {
+            if (tc->finalvel > 0.0 && v_new < 1e-6) {
                 v_new = tc->finalvel;
             }
+        } else {
+            // STOP and EXACT segments must decelerate to zero — never apply
+            // a non-zero backward-pass velocity to their exit fields.
+            v_new = 0.0;
         }
 
         atomicStoreDouble(&tc->shared_9d.final_vel, v_new);

src/emc/motion_planning/motion_planning_9d_userspace.cc

@@ -1468,7 +1468,9 @@ extern "C" int tpAddLine_9D(
                 }
             }
 
-            // Mark for re-optimization (geometry changed)
+            // Invalidate stale profile (target distance changed) so
+            // replanForward recomputes with the new target.
+            __atomic_store_n(&prev_tc->shared_9d.profile.valid, 0, __ATOMIC_RELEASE);
             __atomic_store_n((int*)&prev_tc->shared_9d.optimization_state,
                              TC_PLAN_UNTOUCHED, __ATOMIC_RELEASE);
 

src/emc/tp/tp.c

@@ -5325,8 +5325,10 @@ int tpRunCycle(TP_STRUCT * const tp, long period)
         if (opt_state >= TC_PLAN_OPTIMIZED) {
             double opt_vel = atomicLoadDouble(&tc->shared_9d.final_vel);
 
-            // Sanity check: velocity should be positive and reasonable
-            if (opt_vel > 0.0 && opt_vel < 1e6) {
+            // Sanity check: velocity should be positive and reasonable.
+            // Only apply to TANGENT segments — STOP/EXACT must keep target_vel=0.
+            if (opt_vel > 0.0 && opt_vel < 1e6 &&
+                tc->term_cond == TC_TERM_COND_TANGENT) {
                 tc->target_vel = opt_vel;
                 tc_debug_print("9D: Applied optimized velocity %g (state=%d)\n", opt_vel, opt_state);
             }