use transition only when it has been selected

fix for randomized transitions.
When transitions are selected at random we only have to consume the triggers on the transition that has been selected of out the random candidates.
If we consume the first one, the remaining ones are no longer candidates if they share the same trigger.

Diffs=
6d8854ec04 use transition only when it has been selected (#8921)

Co-authored-by: hernan <hernan@rive.app>

.rive_head

@@ -1 +1 @@
-9a43fe0b417d009ade6057b326e4feb44edb8096
+6d8854ec047020794d0d4babbcad8343d216256a

include/rive/animation/state_transition.hpp

@@ -134,6 +134,10 @@ class StateTransition : public StateTransitionBase
     /// correct time to the animation instance in the stateFrom, when
     /// applicable (when it's an AnimationState).
     bool applyExitCondition(StateInstance* stateFrom) const;
+
+    /// Marks any trigger based condition as used for this layer
+    void useLayerInConditions(StateMachineInstance* stateMachineInstance,
+                              StateMachineLayerInstance* layerInstance) const;
 };
 } // namespace rive
 

src/animation/state_machine_instance.cpp

@@ -238,6 +238,10 @@ class StateMachineLayerInstance
                     }
                 }
             }
+            else
+            {
+                transition->evaluatedRandomWeight(0);
+            }
         }
         if (totalWeight > 0)
         {
@@ -251,6 +255,8 @@ class StateMachineLayerInstance
                 auto transitionWeight = transition->evaluatedRandomWeight();
                 if (currentWeight + transitionWeight > randomWeight)
                 {
+                    transition->useLayerInConditions(m_stateMachineInstance,
+                                                     this);
                     return transition;
                 }
                 currentWeight += transitionWeight;
@@ -284,6 +290,8 @@ class StateMachineLayerInstance
                 {
                     transition->evaluatedRandomWeight(
                         transition->randomWeight());
+                    transition->useLayerInConditions(m_stateMachineInstance,
+                                                     this);
                     return transition;
                 }
                 else

src/animation/state_transition.cpp

@@ -202,15 +202,6 @@ AllowTransition StateTransition::allowed(
             }
         }
     }
-    for (auto condition : m_Conditions)
-    {
-        if (condition->is<TransitionTriggerCondition>())
-        {
-            condition->as<TransitionTriggerCondition>()->useInLayer(
-                stateMachineInstance,
-                layerInstance);
-        }
-    }
     return AllowTransition::yes;
 }
 
@@ -227,4 +218,19 @@ bool StateTransition::applyExitCondition(StateInstance* from) const
         return true;
     }
     return useExitTime;
+}
+
+void StateTransition::useLayerInConditions(
+    StateMachineInstance* stateMachineInstance,
+    StateMachineLayerInstance* layerInstance) const
+{
+    for (auto condition : m_Conditions)
+    {
+        if (condition->is<TransitionTriggerCondition>())
+        {
+            condition->as<TransitionTriggerCondition>()->useInLayer(
+                stateMachineInstance,
+                layerInstance);
+        }
+    }
 }