From 4a1e2b6a68095e6bb7c212be57abb5a1509739b9 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Wed, 2 May 2018 22:22:23 +0300
Subject: [PATCH] Fix a stale pointer issue with Animation

Now that keyframe information is stored in a vector it's no longer
guaranteed that pointers to them stay valid after push_back.  Re-link
all TimedKeyFrames if the vector gets reallocated.
---
 source/animation.cpp | 33 ++++++++++++++++++++++-----------
 source/animation.h   |  1 +
 2 files changed, 23 insertions(+), 11 deletions(-)

diff --git a/source/animation.cpp b/source/animation.cpp
index 61c21ce8..ccd37bca 100644
--- a/source/animation.cpp
+++ b/source/animation.cpp
@@ -42,16 +42,33 @@ const string &Animation::get_uniform_name(unsigned i) const
 }
 
 void Animation::add_keyframe(const Time::TimeDelta &t, const KeyFrame &kf)
+{
+	RefPtr<const KeyFrame> kfr(&kf);
+	kfr.keep();
+	add_keyframe(t, kfr);
+}
+
+void Animation::add_keyframe(const Time::TimeDelta &t, const RefPtr<const KeyFrame> &kf)
 {
 	if(!keyframes.empty() && t<keyframes.back().time)
 		throw invalid_argument("Animation::add_keyframe");
 
-	TimedKeyFrame tkf(*this);
+	bool realloc = (keyframes.size()>=keyframes.capacity());
+
+	keyframes.push_back(TimedKeyFrame(*this));
+	TimedKeyFrame &tkf = keyframes.back();
 	tkf.time = t;
-	tkf.keyframe = &kf;
-	tkf.keyframe.keep();
+	tkf.keyframe = kf;
+
+	if(realloc)
+	{
+		for(unsigned i=1; i<keyframes.size(); ++i)
+			keyframes[i].prev = &keyframes[i-1];
+	}
+	else if(keyframes.size()>1)
+		tkf.prev = &tkf-1;
+
 	prepare_keyframe(tkf);
-	keyframes.push_back(tkf);
 }
 
 void Animation::set_looping(bool l)
@@ -61,8 +78,6 @@ void Animation::set_looping(bool l)
 
 void Animation::prepare_keyframe(TimedKeyFrame &tkf)
 {
-	tkf.prev = (keyframes.empty() ? 0 : &keyframes.back());
-
 	const KeyFrame::UniformMap &kf_uniforms = tkf.keyframe->get_uniforms();
 	for(KeyFrame::UniformMap::const_iterator i=kf_uniforms.begin(); i!=kf_uniforms.end(); ++i)
 	{
@@ -334,11 +349,7 @@ void Animation::Loader::keyframe_inline()
 	else
 		load_sub(*kf);
 
-	TimedKeyFrame tkf(obj);
-	tkf.time = current_time;
-	tkf.keyframe = kf;
-	obj.prepare_keyframe(tkf);
-	obj.keyframes.push_back(tkf);
+	obj.add_keyframe(current_time, kf);
 }
 
 void Animation::Loader::interval(float t)
diff --git a/source/animation.h b/source/animation.h
index 929cb13f..a5f77b46 100644
--- a/source/animation.h
+++ b/source/animation.h
@@ -120,6 +120,7 @@ public:
 
 	void add_keyframe(const Time::TimeDelta &, const KeyFrame &);
 private:
+	void add_keyframe(const Time::TimeDelta &, const RefPtr<const KeyFrame> &);
 	void prepare_keyframe(TimedKeyFrame &);
 
 public:
-- 
2.45.2