From d060780f99d7962b5990c2965cba5fe3b88ee63d Mon Sep 17 00:00:00 2001
From: Gene Payne <payne.gene@gmail.com>
Date: Mon, 22 Mar 2021 12:21:32 -0600
Subject: [PATCH] Added method for saving current value of a property while
 recording

---
 include/openspace/interaction/sessionrecording.h | 13 +++++++++++++
 src/interaction/sessionrecording.cpp             |  8 ++++++++
 src/scene/scene_lua.inl                          |  6 ++++++
 3 files changed, 27 insertions(+)

diff --git a/include/openspace/interaction/sessionrecording.h b/include/openspace/interaction/sessionrecording.h
index 3f52d346a6..a27f6711c6 100644
--- a/include/openspace/interaction/sessionrecording.h
+++ b/include/openspace/interaction/sessionrecording.h
@@ -420,6 +420,18 @@ public:
     void saveScriptKeyframeAscii(Timestamps& times,
         datamessagestructures::ScriptMessage& sm, std::ofstream& file);
 
+    /**
+     * Since session recordings only record changes, the initial conditions aren't
+     * preserved when a playback starts. This function is called whenever a property
+     * value is set and a recording is in progress. Before the set happens, this
+     * function will read the current value of the property and store it so that when
+     * the recording is finished, the initial state will be added as a set property
+     * command at the beginning of the recording file, to be applied when playback
+     * starts.
+     *
+     * \param prop The property being set
+     */
+    void savePropertyBaseline(properties::Property& prop);
     /**
      * Reads header information from a session recording file
      *
@@ -658,6 +670,7 @@ protected:
     std::vector<datamessagestructures::TimeKeyframe> _keyframesTime;
     std::vector<std::string> _keyframesScript;
     std::vector<timelineEntry> _timeline;
+    std::vector<std::string> _keyframesSavePropertiesBaseline;
 
     unsigned int _idxTimeline_nonCamera = 0;
     unsigned int _idxTime = 0;
diff --git a/src/interaction/sessionrecording.cpp b/src/interaction/sessionrecording.cpp
index b5c418708d..10d067480b 100644
--- a/src/interaction/sessionrecording.cpp
+++ b/src/interaction/sessionrecording.cpp
@@ -701,6 +701,14 @@ void SessionRecording::saveScriptKeyframeAscii(Timestamps& times,
     saveKeyframeToFile(keyframeLine.str(), file);
 }
 
+void SessionRecording::savePropertyBaseline(properties::Property& prop) {
+    std::string initialScriptCommand = fmt::format(
+        "openspace.setPropertyValueSingle(\"{}\", {})",
+        prop.fullyQualifiedIdentifier(), prop.getStringValue()
+    );
+    _keyframesSavePropertiesBaseline.push_back(initialScriptCommand);
+}
+
 void SessionRecording::preSynchronization() {
     ZoneScoped
 
diff --git a/src/scene/scene_lua.inl b/src/scene/scene_lua.inl
index ca45fad370..6092fba38c 100644
--- a/src/scene/scene_lua.inl
+++ b/src/scene/scene_lua.inl
@@ -194,6 +194,9 @@ void applyRegularExpression(lua_State* L, const std::string& regex,
             // value change if the types agree
             foundMatching = true;
 
+            if (global::sessionRecording->isRecording()) {
+                global::sessionRecording->savePropertyBaseline(*prop);
+            }
             if (interpolationDuration == 0.0) {
                 global::renderEngine->scene()->removePropertyInterpolation(prop);
                 prop->setLuaValue(L);
@@ -265,6 +268,9 @@ int setPropertyCall_single(properties::Property& prop, const std::string& uri,
         );
     }
     else {
+        if (global::sessionRecording->isRecording()) {
+            global::sessionRecording->savePropertyBaseline(prop);
+        }
         if (duration == 0.0) {
             global::renderEngine->scene()->removePropertyInterpolation(&prop);
             prop.setLuaValue(L);