diff --git a/src/battle/ai.c b/src/battle/ai.c
index 20c2b1a..9d573b3 100644
--- a/src/battle/ai.c
+++ b/src/battle/ai.c
@@ -312,9 +312,9 @@ static void findTarget(void)
 	Entity *e, **candidates;
 	unsigned int dist, closest;
 	
-	dist = closest = (battle.isEpic || (self->aiFlags & AIF_UNLIMITED_RANGE)) ? MAX_TARGET_RANGE : 1000;
+	dist = closest = (battle.isEpic || (self->aiFlags & AIF_UNLIMITED_RANGE)) ? MAX_TARGET_RANGE : SCREEN_WIDTH;
 	
-	candidates = getAllEntsWithin(self->x - (self->w / 2) - dist, self->y - (self->h / 2) - dist, self->w + (dist * 2), self->h + (dist * 2), self);
+	candidates = getAllEntsInRadius(self->x, self->y, dist, self);
 	
 	self->target = NULL;
 	
@@ -588,7 +588,7 @@ static int nearEnemies(void)
 	int i, numEnemies, x, y;
 	Entity *e, **candidates;
 	
-	candidates = getAllEntsWithin(self->x - 500, self->y - 500, 1000, 1000, self);
+	candidates = getAllEntsInRadius(self->x, self->y, SCREEN_WIDTH, self);
 	
 	self->target = NULL;
 	x = y = 0;
@@ -604,7 +604,7 @@ static int nearEnemies(void)
 				continue;
 			}
 			
-			if (getDistance(e->x, e->y, self->x, self->y) < 1000)
+			if (getDistance(e->x, e->y, self->x, self->y) <= SCREEN_WIDTH)
 			{
 				x += e->x;
 				y += e->y;
@@ -658,7 +658,7 @@ static int nearMines(void)
 	int i, numMines;
 	Entity *e, **candidates;
 	
-	candidates = getAllEntsWithin(self->x - 500, self->y - 500, 1000, 1000, self);
+	candidates = getAllEntsInRadius(self->x, self->y, SCREEN_HEIGHT, self);
 	
 	self->targetLocation.x = self->targetLocation.y = 0;
 	
@@ -666,7 +666,7 @@ static int nearMines(void)
 	
 	for (i = 0, e = candidates[i] ; e != NULL ; e = candidates[++i])
 	{
-		if (e->side != self->side && e->type == ET_MINE && getDistance(e->x, e->y, self->x, self->y) < 500)
+		if (e->side != self->side && e->type == ET_MINE && getDistance(e->x, e->y, self->x, self->y) <= SCREEN_HEIGHT)
 		{
 			self->targetLocation.x += e->x;
 			self->targetLocation.y += e->y;
@@ -774,7 +774,7 @@ static int nearItems(void)
 	
 	closest = MAX_TARGET_RANGE;
 	
-	candidates = getAllEntsWithin(self->x - (self->w / 2) - (SCREEN_WIDTH / 4), self->y - (self->h / 2) - (SCREEN_HEIGHT / 4), SCREEN_WIDTH / 2, SCREEN_HEIGHT / 2, self);
+	candidates = getAllEntsInRadius(self->x, self->y, SCREEN_WIDTH / 2, self);
 	
 	self->target = NULL;
 	
@@ -822,7 +822,7 @@ static int nearTowableCraft(void)
 	
 	dist = closest = (battle.isEpic || (self->aiFlags & AIF_UNLIMITED_RANGE)) ? MAX_TARGET_RANGE : 2000;
 	
-	candidates = getAllEntsWithin(self->x - (self->w / 2) - dist, self->y - (self->h / 2) - dist, self->w + (dist * 2), self->h + (dist * 2), self);
+	candidates = getAllEntsInRadius(self->x, self->y, dist, self);
 	
 	self->target = NULL;
 	
diff --git a/src/battle/ai.h b/src/battle/ai.h
index 28823bb..202f8ed 100644
--- a/src/battle/ai.h
+++ b/src/battle/ai.h
@@ -36,7 +36,7 @@ extern float getAngle(int x1, int y1, int x2, int y2);
 extern void applyFighterThrust(void);
 extern void applyFighterBrakes(void);
 extern void addHudMessage(SDL_Color c, char *format, ...);
-extern Entity **getAllEntsWithin(int x, int y, int w, int h, Entity *ignore);
+extern Entity **getAllEntsInRadius(int x, int y, int radius, Entity *ignore);
 extern char *getTranslatedString(char *string);
 extern Entity *spawnMine(int type);
 
diff --git a/src/battle/bullets.c b/src/battle/bullets.c
index 76ae769..d09dbdd 100644
--- a/src/battle/bullets.c
+++ b/src/battle/bullets.c
@@ -339,7 +339,7 @@ static void selectNewTarget(Bullet *b)
 	{
 		b->target = NULL;
 	
-		candidates = getAllEntsWithin(b->x - (SCREEN_WIDTH / 2), b->y - (SCREEN_HEIGHT / 2), SCREEN_WIDTH, SCREEN_HEIGHT, NULL);
+		candidates = getAllEntsInRadius(b->x, b->y, SCREEN_HEIGHT, NULL);
 		
 		for (i = 0, e = candidates[i] ; e != NULL ; e = candidates[++i])
 		{
diff --git a/src/battle/bullets.h b/src/battle/bullets.h
index daa77e5..a7868d7 100644
--- a/src/battle/bullets.h
+++ b/src/battle/bullets.h
@@ -41,6 +41,7 @@ extern void addMissileEngineEffect(Bullet *b);
 extern float mod(float n, float x);
 extern void addMissileExplosion(Bullet *b);
 extern Entity **getAllEntsWithin(int x, int y, int w, int h, Entity *ignore);
+extern Entity **getAllEntsInRadius(int x, int y, int radius, Entity *ignore);
 extern void drawText(int x, int y, int size, int align, SDL_Color c, const char *format, ...);
 extern void playSound(int id);
 extern char *getTranslatedString(char *string);
diff --git a/src/battle/capitalShips.c b/src/battle/capitalShips.c
index ef5cdbb..2a89129 100644
--- a/src/battle/capitalShips.c
+++ b/src/battle/capitalShips.c
@@ -193,7 +193,7 @@ static int steer(void)
 	count = 0;
 	force = 0;
 
-	candidates = getAllEntsWithin(self->x - 1000, self->y - 1000, 2000, 2000, self);
+	candidates = getAllEntsInRadius(self->x, self->y, 2000, self);
 
 	for (i = 0, e = candidates[i] ; e != NULL ; e = candidates[++i])
 	{
diff --git a/src/battle/capitalShips.h b/src/battle/capitalShips.h
index 7a45729..d3d1163 100644
--- a/src/battle/capitalShips.h
+++ b/src/battle/capitalShips.h
@@ -39,7 +39,7 @@ extern float mod(float n, float x);
 extern void applyFighterThrust(void);
 extern void addLargeEngineEffect(void);
 extern int getDistance(int x1, int y1, int x2, int y2);
-extern Entity **getAllEntsWithin(int x, int y, int w, int h, Entity *ignore);
+extern Entity **getAllEntsInRadius(int x, int y, int radius, Entity *ignore);
 extern void addDebris(int x, int y, int amount);
 extern void runScriptFunction(char *format, ...);
 extern void updateObjective(char *name, int type);
diff --git a/src/battle/fighters.c b/src/battle/fighters.c
index c1ecde3..63aab77 100644
--- a/src/battle/fighters.c
+++ b/src/battle/fighters.c
@@ -345,7 +345,7 @@ static void separate(void)
 	count = 0;
 	force = 0;
 
-	candidates = getAllEntsWithin(self->x - (self->w / 2), self->y - (self->h / 2), self->w, self->h, self);
+	candidates = getAllEntsInRadius(self->x, self->y, self->separationRadius, self);
 
 	for (i = 0, e = candidates[i] ; e != NULL ; e = candidates[++i])
 	{
diff --git a/src/battle/fighters.h b/src/battle/fighters.h
index c263834..67f6d1e 100644
--- a/src/battle/fighters.h
+++ b/src/battle/fighters.h
@@ -33,7 +33,7 @@ extern void playBattleSound(int id, int x, int y);
 extern void updateObjective(char *name, int type);
 extern void updateCondition(char *name, int type);
 extern void addHudMessage(SDL_Color c, char *format, ...);
-extern Entity **getAllEntsWithin(int x, int y, int w, int h, Entity *ignore);
+extern Entity **getAllEntsInRadius(int x, int y, int radius, Entity *ignore);
 extern Entity *spawnEntity(void);
 extern void adjustObjectiveTargetValue(char *name, int type, int amount);
 extern void attachRope(void);
diff --git a/src/battle/items.c b/src/battle/items.c
index 07fb2d9..bd79b85 100644
--- a/src/battle/items.c
+++ b/src/battle/items.c
@@ -101,7 +101,7 @@ static void action(void)
 	Entity *e, **candidates;
 	int i;
 
-	candidates = getAllEntsWithin(self->x - (self->w / 2), self->y - (self->h / 2), self->w, self->h, self);
+	candidates = getAllEntsInRadius(self->x, self->y, MAX(self->w, self->h), self);
 
 	for (i = 0, e = candidates[i] ; e != NULL ; e = candidates[++i])
 	{
diff --git a/src/battle/items.h b/src/battle/items.h
index 5d54998..3be5f74 100644
--- a/src/battle/items.h
+++ b/src/battle/items.h
@@ -25,7 +25,7 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 extern char *readFile(char *filename);
 extern SDL_Texture *getTexture(char *filename);
 extern Entity *spawnEntity(void);
-extern Entity **getAllEntsWithin(int x, int y, int w, int h, Entity *ignore);
+extern Entity **getAllEntsInRadius(int x, int y, int radius, Entity *ignore);
 extern int collision(int x1, int y1, int w1, int h1, int x2, int y2, int w2, int h2);
 extern void playBattleSound(int id, int x, int y);
 extern void addHudMessage(SDL_Color c, char *format, ...);
diff --git a/src/battle/jumpgate.c b/src/battle/jumpgate.c
index 2754fd1..bab6fbf 100644
--- a/src/battle/jumpgate.c
+++ b/src/battle/jumpgate.c
@@ -172,11 +172,11 @@ static void handleFleeingEntities(void)
 	Entity *e, **candidates;
 	int i;
 
-	candidates = getAllEntsWithin(self->x - (self->w / 2), self->y - (self->h / 2), self->w, self->h, self);
+	candidates = getAllEntsInRadius(self->x, self->y, ESCAPE_DISTANCE * 2, self);
 
 	for (i = 0, e = candidates[i] ; e != NULL ; e = candidates[++i])
 	{
-		if (e->health > 0 && e->flags & EF_RETREATING && getDistance(self->x, self->y, e->x, e->y) <= 255)
+		if (e->health > 0 && e->flags & EF_RETREATING && getDistance(self->x, self->y, e->x, e->y) <= ESCAPE_DISTANCE)
 		{
 			e->alive = ALIVE_ESCAPED;
 
diff --git a/src/battle/jumpgate.h b/src/battle/jumpgate.h
index 860c56d..f0a76b1 100644
--- a/src/battle/jumpgate.h
+++ b/src/battle/jumpgate.h
@@ -20,9 +20,11 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 #include "../common.h"
 
+#define ESCAPE_DISTANCE 256
+
 extern SDL_Texture *getTexture(char *filename);
 extern Entity *spawnEntity(void);
-extern Entity **getAllEntsWithin(int x, int y, int w, int h, Entity *ignore);
+extern Entity **getAllEntsInRadius(int x, int y, int radius, Entity *ignore);
 extern int getDistance(int x1, int y1, int x2, int y2);
 extern void playBattleSound(int id, int x, int y);
 extern void blitRotated(SDL_Texture *texture, int x, int y, float angle);
diff --git a/src/battle/mine.c b/src/battle/mine.c
index a66d9e7..b53e7ad 100644
--- a/src/battle/mine.c
+++ b/src/battle/mine.c
@@ -99,7 +99,7 @@ static void lookForFighters(void)
 	Entity *e, **candidates;
 	int i;
 
-	candidates = getAllEntsWithin(self->x - (self->w / 2) - DAMAGE_RANGE, self->y - (self->h / 2) - DAMAGE_RANGE, self->w + DAMAGE_RANGE, self->h + DAMAGE_RANGE, self);
+	candidates = getAllEntsInRadius(self->x, self->y, DAMAGE_RANGE, self);
 
 	for (i = 0, e = candidates[i] ; e != NULL ; e = candidates[++i])
 	{
@@ -199,7 +199,7 @@ static void doSplashDamage(void)
 	int i, dist, kills;
 	float damage, percent;
 
-	candidates = getAllEntsWithin(self->x - (self->w / 2), self->y - (self->h / 2), self->w, self->h, self);
+	candidates = getAllEntsInRadius(self->x, self->y, DAMAGE_RANGE, self);
 	
 	kills = 0;
 
diff --git a/src/battle/mine.h b/src/battle/mine.h
index 91d3582..aeeadd8 100644
--- a/src/battle/mine.h
+++ b/src/battle/mine.h
@@ -21,12 +21,12 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 #include "../common.h"
 
 #define TRIGGER_RANGE	150
-#define DAMAGE_RANGE	275
+#define DAMAGE_RANGE	250
 #define SYSTEM_POWER	50
 
 extern Entity *spawnEntity(void);
 extern SDL_Texture *getTexture(char *filename);
-extern Entity **getAllEntsWithin(int x, int y, int w, int h, Entity *ignore);
+extern Entity **getAllEntsInRadius(int x, int y, int radius, Entity *ignore);
 extern int getDistance(int x1, int y1, int x2, int y2);
 extern void addMineExplosion(void);
 extern void damageFighter(Entity *e, int amount, long flags);
diff --git a/src/battle/quadtree.c b/src/battle/quadtree.c
index 76e644d..cecb6c4 100644
--- a/src/battle/quadtree.c
+++ b/src/battle/quadtree.c
@@ -233,6 +233,11 @@ Entity **getAllEntsWithin(int x, int y, int w, int h, Entity *ignore)
 	return candidates;
 }
 
+Entity **getAllEntsInRadius(int x, int y, int radius, Entity *ignore)
+{
+	return getAllEntsWithin(x - radius / 2, y - radius / 2, radius, radius, ignore);
+}
+
 static void getAllEntsWithinNode(int x, int y, int w, int h, Entity *ignore, Quadtree *root)
 {
 	int index, i;
diff --git a/src/battle/rope.c b/src/battle/rope.c
index 83ad9ce..2e577a2 100644
--- a/src/battle/rope.c
+++ b/src/battle/rope.c
@@ -27,7 +27,7 @@ void attachRope(void)
 	
 	if ((self->flags & EF_HAS_ROPE) && self->towing == NULL)
 	{
-		candidates = getAllEntsWithin(self->x - (self->w / 2), self->y - (self->h / 2), self->w, self->h, self);
+		candidates = getAllEntsInRadius(self->x, self->y, self->separationRadius, self);
 	
 		for (i = 0, e = candidates[i] ; e != NULL ; e = candidates[++i])
 		{
diff --git a/src/battle/rope.h b/src/battle/rope.h
index 39d76ff..c8dc18e 100644
--- a/src/battle/rope.h
+++ b/src/battle/rope.h
@@ -24,7 +24,7 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 extern float getAngle(int x1, int y1, int x2, int y2);
 extern int getDistance(int x1, int y1, int x2, int y2);
-extern Entity **getAllEntsWithin(int x, int y, int w, int h, Entity *ignore);
+extern Entity **getAllEntsInRadius(int x, int y, int radius, Entity *ignore);
 extern void addHudMessage(SDL_Color c, char *format, ...);
 extern void runScriptFunction(char *format, ...);
 extern char *getTranslatedString(char *string);