From fb235212882b3a2ea506d74394a01fc7dd181a98 Mon Sep 17 00:00:00 2001
From: obligaron <obligaron@live.com>
Date: Tue, 22 Jun 2021 17:06:46 +0200
Subject: [PATCH] Introduce AnimationInfo.IsPetrified to handle Stone Curse
 Spell

---
 Source/engine/animationinfo.cpp | 14 +++++++++++---
 Source/engine/animationinfo.h   |  9 +++++++++
 Source/missiles.cpp             |  6 ++++--
 Source/monster.cpp              |  1 +
 4 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/Source/engine/animationinfo.cpp b/Source/engine/animationinfo.cpp
index 50911896f..a801109d4 100644
--- a/Source/engine/animationinfo.cpp
+++ b/Source/engine/animationinfo.cpp
@@ -26,7 +26,7 @@ int AnimationInfo::GetFrameToUseForRendering() const
 	assert(TicksSinceSequenceStarted >= 0);
 
 	// we don't use the processed game ticks alone but also the fraction of the next game tick (if a rendering happens between game ticks). This helps to smooth the animations.
-	float totalTicksForCurrentAnimationSequence = gfProgressToNextGameTick + (float)TicksSinceSequenceStarted;
+	float totalTicksForCurrentAnimationSequence = GetProgressToNextGameTick() + (float)TicksSinceSequenceStarted;
 
 	// 1 added for rounding reasons. float to int cast always truncate.
 	int absoluteAnimationFrame = 1 + (int)(totalTicksForCurrentAnimationSequence * TickModifier);
@@ -58,12 +58,12 @@ float AnimationInfo::GetAnimationProgress() const
 		// This logic is used if animation distrubtion is not active (see GetFrameToUseForRendering).
 		// In this case the variables calculated with animation distribution are not initialized and we have to calculate them on the fly with the given informations.
 		float ticksPerFrame = (DelayLen + 1);
-		float totalTicksForCurrentAnimationSequence = gfProgressToNextGameTick + (float)CurrentFrame + (DelayCounter / ticksPerFrame);
+		float totalTicksForCurrentAnimationSequence = GetProgressToNextGameTick() + (float)CurrentFrame + (DelayCounter / ticksPerFrame);
 		float fAnimationFraction = totalTicksForCurrentAnimationSequence / ((float)NumberOfFrames * ticksPerFrame);
 		return fAnimationFraction;
 	}
 
-	float totalTicksForCurrentAnimationSequence = gfProgressToNextGameTick + (float)TicksSinceSequenceStarted;
+	float totalTicksForCurrentAnimationSequence = GetProgressToNextGameTick() + (float)TicksSinceSequenceStarted;
 	float fProgressInAnimationFrames = totalTicksForCurrentAnimationSequence * TickModifier;
 	float fAnimationFraction = fProgressInAnimationFrames / (float)NumberOfFrames;
 	return fAnimationFraction;
@@ -87,6 +87,7 @@ void AnimationInfo::SetNewAnimation(CelSprite *pCelSprite, int numberOfFrames, i
 	TicksSinceSequenceStarted = 0;
 	RelevantFramesForDistributing = 0;
 	TickModifier = 0.0F;
+	IsPetrified = false;
 
 	if (numSkippedFrames != 0 || flags != AnimationDistributionFlags::None) {
 		// Animation Frames that will be adjusted for the skipped Frames/game ticks
@@ -194,4 +195,11 @@ void AnimationInfo::ProcessAnimation(bool reverseAnimation /*= false*/, bool don
 	}
 }
 
+float AnimationInfo::GetProgressToNextGameTick() const
+{
+	if (IsPetrified)
+		return 0.0f;
+	return gfProgressToNextGameTick;
+}
+
 } // namespace devilution
diff --git a/Source/engine/animationinfo.h b/Source/engine/animationinfo.h
index 3f17da79c..69bbc3e37 100644
--- a/Source/engine/animationinfo.h
+++ b/Source/engine/animationinfo.h
@@ -56,6 +56,10 @@ public:
 	 * @brief Current frame of animation
 	 */
 	int CurrentFrame;
+	/**
+	 * @brief Is the animation currently petrified and shouldn't advance with gfProgressToNextGameTick
+	 */
+	bool IsPetrified;
 
 	/**
 	 * @brief Calculates the Frame to use for the Animation rendering
@@ -95,6 +99,11 @@ public:
 	void ProcessAnimation(bool reverseAnimation = false, bool dontProgressAnimation = false);
 
 private:
+	/**
+	 * @brief returns the progress as a fraction (0.0f to 1.0f) in time to the next game tick or 0.0f if the animation is frozen
+	*/
+	float GetProgressToNextGameTick() const;
+
 	/**
 	 * @brief Specifies how many animations-fractions are displayed between two game ticks. this can be > 0, if animations are skipped or < 0 if the same animation is shown in multiple times (delay specified).
 	 */
diff --git a/Source/missiles.cpp b/Source/missiles.cpp
index 786756577..2e5367fbf 100644
--- a/Source/missiles.cpp
+++ b/Source/missiles.cpp
@@ -4349,10 +4349,12 @@ void MI_Stone(int i)
 
 	if (missile[i]._mirange == 0) {
 		missile[i]._miDelFlag = true;
-		if (monster[m]._mhitpoints > 0)
+		if (monster[m]._mhitpoints > 0) {
 			monster[m]._mmode = (MON_MODE)missile[i]._miVar1;
-		else
+			monster[m].AnimInfo.IsPetrified = false;
+		} else {
 			AddDead(monster[m].position.tile, stonendx, monster[m]._mdir);
+		}
 	}
 	if (missile[i]._miAnimType == MFILE_SHATTER1)
 		PutMissile(i);
diff --git a/Source/monster.cpp b/Source/monster.cpp
index 79768d6e2..027bd10af 100644
--- a/Source/monster.cpp
+++ b/Source/monster.cpp
@@ -5422,6 +5422,7 @@ void MonsterStruct::CheckStandAnimationIsLoaded(int mdir)
 void MonsterStruct::Petrify()
 {
 	_mmode = MM_STONE;
+	AnimInfo.IsPetrified = true;
 }
 
 } // namespace devilution