From 90ad1fd8564f8a305932b1488159c1f784c04ae8 Mon Sep 17 00:00:00 2001
From: Simon Robertshaw <simon@hardwired.org.uk>
Date: Sun, 29 Jul 2012 12:29:19 +0100
Subject: [PATCH] Restart N. Grav when needed (somewhat effects issue #31) and
 fix shitty logic when setting paused state on loading save (Fixes issue #34)

---
 src/game/GameModel.cpp     | 10 +++-------
 src/simulation/Gravity.cpp | 20 ++++++++++++--------
 2 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/src/game/GameModel.cpp b/src/game/GameModel.cpp
index fef4e6171..b2f7d700f 100644
--- a/src/game/GameModel.cpp
+++ b/src/game/GameModel.cpp
@@ -289,19 +289,15 @@ void GameModel::SetSave(SaveInfo * newSave)
 	if(currentSave && currentSave->GetGameSave())
 	{
 		GameSave * saveData = currentSave->GetGameSave();
-		SetPaused(saveData->paused & GetPaused());
+		SetPaused(saveData->paused | GetPaused());
 		sim->gravityMode = saveData->gravityMode;
 		sim->air->airMode = saveData->airMode;
 		sim->legacy_enable = saveData->legacyEnable;
 		sim->water_equal_test = saveData->waterEEnabled;
-		if(saveData->gravityEnable && !sim->grav->ngrav_enable)
-		{
+		if(saveData->gravityEnable)
 			sim->grav->start_grav_async();
-		}
-		else if(!saveData->gravityEnable && sim->grav->ngrav_enable)
-		{
+		else
 			sim->grav->stop_grav_async();
-		}
 		sim->clear_sim();
 		sim->Load(saveData);
 	}
diff --git a/src/simulation/Gravity.cpp b/src/simulation/Gravity.cpp
index 2b7810d90..89f626ea9 100644
--- a/src/simulation/Gravity.cpp
+++ b/src/simulation/Gravity.cpp
@@ -167,17 +167,20 @@ void Gravity::update_grav_async()
 
 void Gravity::start_grav_async()
 {
-	if(!ngrav_enable){
-		gravthread_done = 0;
-		grav_ready = 0;
-		pthread_mutex_init (&gravmutex, NULL);
-		pthread_cond_init(&gravcv, NULL);
-		pthread_create(&gravthread, NULL, &Gravity::update_grav_async_helper, this); //Start asynchronous gravity simulation
-		ngrav_enable = 1;
-	}
+	if(ngrav_enable)	//If it's already enabled, restart it
+		stop_grav_async();
+
+	gravthread_done = 0;
+	grav_ready = 0;
+	pthread_mutex_init (&gravmutex, NULL);
+	pthread_cond_init(&gravcv, NULL);
+	pthread_create(&gravthread, NULL, &Gravity::update_grav_async_helper, this); //Start asynchronous gravity simulation
+	ngrav_enable = 1;
+
 	memset(gravy, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
 	memset(gravx, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
 	memset(gravp, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
+	memset(gravmap, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
 }
 
 void Gravity::stop_grav_async()
@@ -195,6 +198,7 @@ void Gravity::stop_grav_async()
 	memset(gravy, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
 	memset(gravx, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
 	memset(gravp, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
+	memset(gravmap, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
 }
 
 #ifdef GRAVFFT