Fix displaying effects with random durations (#19)

src/client/animator.cpp

@@ -125,14 +125,21 @@ int Animator::getPhase()
     return m_phase;
 }
 
-int Animator::getPhaseAt(Timer& timer, int lastPhase)
+static uint32 getRandomVal(uint32_t seed, int iterations)
+{
+    for (int i = 0; i < iterations; i++) {
+        seed = seed * 17 + 3;
+    }
+    return seed;
+}
+
+int Animator::getPhaseAt(Timer& timer, uint32_t randomSeed, int lastPhase)
 {
-    static int rand_val = 6;
     ticks_t time = timer.ticksElapsed();
     for (int i = lastPhase; i < m_animationPhases; ++i) {
         int phaseDuration = m_phaseDurations[i].second == 0 ? 
-            m_phaseDurations[i].first : m_phaseDurations[i].first + rand_val % (m_phaseDurations[i].second);
-        rand_val = rand_val * 7 + 11;
+            m_phaseDurations[i].first : m_phaseDurations[i].first + getRandomVal(randomSeed, i) % (m_phaseDurations[i].second);
+
         if (time < phaseDuration) {
             timer.restart();
             timer.adjust(-time);
@@ -233,11 +240,14 @@ void Animator::calculateSynchronous()
     m_lastPhaseTicks = ticks;
 }
 
-ticks_t Animator::getTotalDuration()
+ticks_t Animator::getTotalDuration(uint32_t randomSeed)
 {
     ticks_t time = 0;
+    int i = 0;
     for (const auto &pair: m_phaseDurations) {
-        time += pair.first + pair.second;
+        int phaseDuration = pair.second == 0 ? 
+            pair.first : pair.first + getRandomVal(randomSeed, i++) % (pair.second);
+        time += phaseDuration;
     }
 
     return time;

src/client/animator.h

@@ -51,14 +51,14 @@ class Animator : public std::enable_shared_from_this<Animator>
 
     void setPhase(int phase);
     int getPhase();
-    int getPhaseAt(Timer& timer, int lastPhase = 0);
+    int getPhaseAt(Timer& timer, uint32_t randomSeed, int lastPhase = 0);
 
     int getStartPhase();
     int getAnimationPhases() { return m_animationPhases; }
     bool isAsync() { return m_async; }
     bool isComplete() { return m_isComplete; }
 
-    ticks_t getTotalDuration();
+    ticks_t getTotalDuration(uint32_t randomSeed);
 
     void resetAnimation();
 

src/client/effect.cpp

@@ -25,6 +25,7 @@
 #include "game.h"
 #include <framework/core/eventdispatcher.h>
 #include <framework/util/extras.h>
+#include <framework/stdext/fastrand.h>
 
 void Effect::draw(const Point& dest, int offsetX, int offsetY, bool animate, LightView* lightView)
 {
@@ -34,7 +35,7 @@ void Effect::draw(const Point& dest, int offsetX, int offsetY, bool animate, Lig
     if(animate) {
         if(g_game.getFeature(Otc::GameEnhancedAnimations) && rawGetThingType()->getAnimator()) {
             // This requires a separate getPhaseAt method as using getPhase would make all magic effects use the same phase regardless of their appearance time
-            m_animationPhase = std::max<int>(0, rawGetThingType()->getAnimator()->getPhaseAt(m_animationTimer, m_animationPhase));
+            m_animationPhase = std::max<int>(0, rawGetThingType()->getAnimator()->getPhaseAt(m_animationTimer, m_randomSeed, m_animationPhase));
         } else {
             // hack to fix some animation phases duration, currently there is no better solution
             int ticks = EFFECT_TICKS_PER_FRAME;
@@ -63,7 +64,8 @@ void Effect::onAppear()
 
     int duration = 0;
     if(g_game.getFeature(Otc::GameEnhancedAnimations)) {
-        duration = getThingType()->getAnimator() ? getThingType()->getAnimator()->getTotalDuration() : 1000;
+        m_randomSeed = (uint32_t)stdext::fastrand();
+        duration = getThingType()->getAnimator() ? getThingType()->getAnimator()->getTotalDuration(m_randomSeed) : 1000;
     } else {
         duration = EFFECT_TICKS_PER_FRAME;
 

src/client/effect.h

@@ -54,6 +54,7 @@ class Effect : public Thing
     uint16 m_id;
     Timer m_animationTimer;
     int m_animationPhase = 0;
+    uint32 m_randomSeed;
 };
 
 #endif