diff --git a/src/droid.c b/src/droid.c
index 2f1bbe29d..b8b6d1bcb 100644
--- a/src/droid.c
+++ b/src/droid.c
@@ -2534,6 +2534,7 @@ DROID* buildDroid(DROID_TEMPLATE *pTemplate, UDWORD x, UDWORD y, UDWORD player,
 	psDroid->resistance = ACTION_START_TIME;
 
 	memset(psDroid->visible, 0, sizeof(psDroid->visible));
+	memset(psDroid->visible, 0, sizeof(psDroid->seenThisTick));
 	psDroid->visible[psDroid->player] = UBYTE_MAX;
 	psDroid->died = 0;
 	psDroid->inFire = false;
diff --git a/src/feature.c b/src/feature.c
index 2977dba6b..5dd7ad446 100644
--- a/src/feature.c
+++ b/src/feature.c
@@ -354,12 +354,10 @@ FEATURE * buildFeature(FEATURE_STATS *psStats, UDWORD x, UDWORD y,BOOL FromSave)
 		}
 	}
 
-	for(i=0; i<MAX_PLAYERS; i++)
-	{
-		psFeature->visible[i] = 0;//vis;
-	}
-	//load into the map data
+	memset(psFeature->seenThisTick, 0, sizeof(psFeature->seenThisTick));
+	memset(psFeature->visible, 0, sizeof(psFeature->visible));
 
+	//load into the map data
 	if(FromSave) {
 		mapX = map_coord(x) - psStats->baseWidth / 2;
 		mapY = map_coord(y) - psStats->baseBreadth / 2;
@@ -523,10 +521,8 @@ bool removeFeature(FEATURE *psDel)
 
 	if (psDel->psStats->subType == FEAT_GEN_ARTE || psDel->psStats->subType == FEAT_OIL_RESOURCE)
 	{
-		// have to check all players cos if you cheat you'll get em.
 		for (player = 0; player < MAX_PLAYERS; player++)
 		{
-			//see if there is a proximity message FOR THE SELECTED PLAYER at this location
 			psMessage = findMessage((MSG_VIEWDATA *)psDel, MSG_PROXIMITY, player);
 			while (psMessage)
 			{
diff --git a/src/structure.c b/src/structure.c
index 850ce6ce8..a152d59ba 100644
--- a/src/structure.c
+++ b/src/structure.c
@@ -1783,8 +1783,9 @@ STRUCTURE* buildStructure(STRUCTURE_STATS* pStructureType, UDWORD x, UDWORD y, U
 		psBuilding->resistance = (UWORD)structureResistance(pStructureType, (UBYTE)player);
 		psBuilding->lastResistance = ACTION_START_TIME;
 
-		//do the visiblilty stiff before setFunctionality - so placement of DP's can work
-		memset(psBuilding->visible, 0, (sizeof(UBYTE) * MAX_PLAYERS) );
+		// Do the visibility stuff before setFunctionality - so placement of DP's can work
+		memset(psBuilding->visible, 0, sizeof(psBuilding->visible));
+		memset(psBuilding->seenThisTick, 0, sizeof(psBuilding->seenThisTick));
 
 		/* Structure is trivially visible to the builder (owner) */
 		psBuilding->visible[player] = UBYTE_MAX;